Generally speaking,the precursors of ozone(O_(3)),nitrogen oxides and volatile organic compounds are very low in desert areas due to the lack of anthropogenic emissions and natural emissions,and thus O_(3)concentratio...Generally speaking,the precursors of ozone(O_(3)),nitrogen oxides and volatile organic compounds are very low in desert areas due to the lack of anthropogenic emissions and natural emissions,and thus O_(3)concentrations are relatively low.However,high summer background concentrations of about 100μg/m^(3)or 60 ppb were found in the Alxa Desert in the highland of northwest China based on continuous summer observations from 2019 to 2021,which was higher than the most of natural background areas or clean areas in world for summer O_(3)background concentrations.The high O_(3)background concentrations were related to surface features and altitude.Heavy-intensity anthropogenic activity areas in desert areas can cause increased O_(3)concentrations or pollution,but also generated O_(3)depleting substances such as nitrous oxide,which eventually reduced the regional O_(3)baseline values.Nitrogen dioxide(NO2)also had a dual effect on O_(3)generation,showing promotion at low concentrations and inhibition at high concentrations.In addition,sand-dust weather reduced O_(3)clearly,but O_(3)eventually stabilized around the background concentration values and did not vary with sand-dust particulate matter.展开更多
As a vital type of light-absorbing aerosol,brown carbon(BrC)presents inherent associations with atmospheric photochemistry and climate change.However,the understanding of the chemical and optical properties of BrC is ...As a vital type of light-absorbing aerosol,brown carbon(BrC)presents inherent associations with atmospheric photochemistry and climate change.However,the understanding of the chemical and optical properties of BrC is limited,especially in some resource-dependent cities with long heating periods in northwest China.This study showed that the annual average abundances of Water-soluble BrC(WS-BrC)were 9.33±7.42 and 8.69±6.29μg/m^(3)in Baotou and Wuhai and the concentrations,absorption coefficient(Abs_(365)),and mass absorption efficiency(MAE365)of WS-BrC presented significant seasonal patterns,with high values in the heating season and low values in the non-heating season;while showing opposite seasonal trends for the Absorption Angstr?m exponent(AAE_(300-400)).Comparatively,the levels of WS-BrC in developing regions(such as cities in Asia)were higher than those in developed regions(such as cities in Europe and Australia),indicating the significant differences in energy consumption in these regions.By combining fluorescence excitation-emission matrix(EEM)spectra with the parallel factor(PARAFAC)model,humic-like(C1 and C2)and proteinlike(C3)substances were identified,and accounted for 61.40%±4.66%and 38.6%±3.78%at Baotou,and 60.33%±6.29%and 39.67%±4.17%at Wuhai,respectively.The results of source apportionment suggested that the potential source regions of WS-BrC varied in heating vs.non-heating seasons and that the properties of WS-BrC significantly depended on primary emissions(e.g.,combustion emissions)and secondary formation.展开更多
Granulocyte-macrophage colony-stimulating factor （GM-CSF） is known to be a potential vaccine adjuvant despite contradictory results from animal and human studies. The discrepancies may be due to the different doses ...Granulocyte-macrophage colony-stimulating factor （GM-CSF） is known to be a potential vaccine adjuvant despite contradictory results from animal and human studies. The discrepancies may be due to the different doses and regimens of GM-CSF that were used, given that either mature or immature dendritic cells （DCs） could be induced under different conditions. To test the hypothesis that GM-CSF can be used as a novel adjuvant for a hepatitis B virus （HBV） therapeutic vaccine, we administered GM-CSF once per day for three days prior to vaccination with recombinant HBV vaccine （rHBVvac） in mice. We observed greater DC maturation in these pre-treated animals at day 3 as compared to day 1 or day 2 of daily GM-CSF administration. This strategy was further investigated for its ability to break the immune tolerance established in hepatitis B surface antigen-transgenic （HBsAg-Tg） animals. We found that the levels of induced anti-HBsAg antibodies were significantly higher in animals following three days of GM-CSF pre-treatment before rHBV vaccination after the third immunization. In addition to the increase in anti-HBsAg antibody levels, cell-mediated anti-HBsAg responses, including delayed-type hypersensitivity, T-cell proliferation, interferon-y production, and cytotoxic T lymphocytes, were dramatically enhanced in the three-day GM-CSF pre-treated group. After adoptive transfers of CD8＋ T cells from immunized animals, antigen-specific CD8＋ T cells were observed in the livers of recipient HBsAg-Tg animals. Moreover, the three-day pre-treatments with GM-CSF prior to rHBVvac vaccination could significantly eliminate HBsAg-positive hepatocytes, suggesting beneficial therapeutic effects. Therefore, this protocol utilizing GM-CSF as an adjuvant in combination with the rHBVvac vaccine has the potential to become a novel immunotherapy for chronic hepatitis B patients.展开更多
基金supported by the Ministry of Science and Technology of China(No.2022YFF0802501)Inner Mongolia Autonomous Region Science and Technology Program(Nos.2021GG0100 and 2022YFHH0116).
文摘Generally speaking,the precursors of ozone(O_(3)),nitrogen oxides and volatile organic compounds are very low in desert areas due to the lack of anthropogenic emissions and natural emissions,and thus O_(3)concentrations are relatively low.However,high summer background concentrations of about 100μg/m^(3)or 60 ppb were found in the Alxa Desert in the highland of northwest China based on continuous summer observations from 2019 to 2021,which was higher than the most of natural background areas or clean areas in world for summer O_(3)background concentrations.The high O_(3)background concentrations were related to surface features and altitude.Heavy-intensity anthropogenic activity areas in desert areas can cause increased O_(3)concentrations or pollution,but also generated O_(3)depleting substances such as nitrous oxide,which eventually reduced the regional O_(3)baseline values.Nitrogen dioxide(NO2)also had a dual effect on O_(3)generation,showing promotion at low concentrations and inhibition at high concentrations.In addition,sand-dust weather reduced O_(3)clearly,but O_(3)eventually stabilized around the background concentration values and did not vary with sand-dust particulate matter.
基金supported by the Science and Technology Major Project of Natural Science Foundation of Inner Mongolia,China(No.21800-5173909)the Science and Technology Major Project on Air Pollution Prevention and Prediction in Hohhot-Baotou-Ordos Cities Group of Inner Mongolia(No.2020ZD0013)+1 种基金the Young Scientific&Technological Leading Talent Program of Inner Mongolia(No.NJYT2022092)the Science Fund for Distinguished Young Scholars of Inner Mongolia(No.2019JQ05)。
文摘As a vital type of light-absorbing aerosol,brown carbon(BrC)presents inherent associations with atmospheric photochemistry and climate change.However,the understanding of the chemical and optical properties of BrC is limited,especially in some resource-dependent cities with long heating periods in northwest China.This study showed that the annual average abundances of Water-soluble BrC(WS-BrC)were 9.33±7.42 and 8.69±6.29μg/m^(3)in Baotou and Wuhai and the concentrations,absorption coefficient(Abs_(365)),and mass absorption efficiency(MAE365)of WS-BrC presented significant seasonal patterns,with high values in the heating season and low values in the non-heating season;while showing opposite seasonal trends for the Absorption Angstr?m exponent(AAE_(300-400)).Comparatively,the levels of WS-BrC in developing regions(such as cities in Asia)were higher than those in developed regions(such as cities in Europe and Australia),indicating the significant differences in energy consumption in these regions.By combining fluorescence excitation-emission matrix(EEM)spectra with the parallel factor(PARAFAC)model,humic-like(C1 and C2)and proteinlike(C3)substances were identified,and accounted for 61.40%±4.66%and 38.6%±3.78%at Baotou,and 60.33%±6.29%and 39.67%±4.17%at Wuhai,respectively.The results of source apportionment suggested that the potential source regions of WS-BrC varied in heating vs.non-heating seasons and that the properties of WS-BrC significantly depended on primary emissions(e.g.,combustion emissions)and secondary formation.
文摘Granulocyte-macrophage colony-stimulating factor （GM-CSF） is known to be a potential vaccine adjuvant despite contradictory results from animal and human studies. The discrepancies may be due to the different doses and regimens of GM-CSF that were used, given that either mature or immature dendritic cells （DCs） could be induced under different conditions. To test the hypothesis that GM-CSF can be used as a novel adjuvant for a hepatitis B virus （HBV） therapeutic vaccine, we administered GM-CSF once per day for three days prior to vaccination with recombinant HBV vaccine （rHBVvac） in mice. We observed greater DC maturation in these pre-treated animals at day 3 as compared to day 1 or day 2 of daily GM-CSF administration. This strategy was further investigated for its ability to break the immune tolerance established in hepatitis B surface antigen-transgenic （HBsAg-Tg） animals. We found that the levels of induced anti-HBsAg antibodies were significantly higher in animals following three days of GM-CSF pre-treatment before rHBV vaccination after the third immunization. In addition to the increase in anti-HBsAg antibody levels, cell-mediated anti-HBsAg responses, including delayed-type hypersensitivity, T-cell proliferation, interferon-y production, and cytotoxic T lymphocytes, were dramatically enhanced in the three-day GM-CSF pre-treated group. After adoptive transfers of CD8＋ T cells from immunized animals, antigen-specific CD8＋ T cells were observed in the livers of recipient HBsAg-Tg animals. Moreover, the three-day pre-treatments with GM-CSF prior to rHBVvac vaccination could significantly eliminate HBsAg-positive hepatocytes, suggesting beneficial therapeutic effects. Therefore, this protocol utilizing GM-CSF as an adjuvant in combination with the rHBVvac vaccine has the potential to become a novel immunotherapy for chronic hepatitis B patients.
