Sunshine duration(SD) is adopted widely to study global dimming/brightening. However, long-term simultaneous measurements of SD and closely related impact factors require further analysis to elucidate how and why SD h...Sunshine duration(SD) is adopted widely to study global dimming/brightening. However, long-term simultaneous measurements of SD and closely related impact factors require further analysis to elucidate how and why SD has varied during the past decades. In this study, a long-term(1958–2021) SD data series obtained from the Shangdianzi Global Atmosphere Watch(GAW) station in China was analyzed to detect linear trends, climatic jumps, and climatic periods in SD using linear fitting, the Mann–Kendall trend test, and the continuous wavelet transform method. Annual SD exhibited steady dimming(-67.3 h decade-1) before 2010, followed by a period of brightening(189.9 h decade-1)during 2011–2020. An abrupt jump in annual SD occurred in 1995, and the annual SD anomaly exhibited significant oscillation with ~3-yr periodicity during 1960–1978. Partial least squares analysis revealed that annual SD anomaly was associated with variations in relative humidity, gale days, cloud cover, and black carbon(BC). Further analysis of the clear-sky daily sunshine percentage(DSP) and simultaneous measurements of aerosol properties, including aerosol optical depth, aerosol extinction coefficient, single scattering albedo(SSA), BC, and total suspended particulates, suggested that variation in DSP was affected primarily by aerosol scattering and absorption. Furthermore, the hourly clear-sky SD at high aerosol loading was approximately 60% and 56% of that at middle and low aerosol loadings, respectively. The pattern of diurnal variation in clear-sky hourly SD, as well as the actual values, can be affected by the fine particulate concentration, aerosol extinction coefficient, and SSA.展开更多
Background:Metaplastic breast carcinoma(MBC)is a rare breast cancer subtype;most cases are triple‐negative breast cancers(TNBCs)and are poorly responsive to conventional systemic therapy.Few potential diagnostic and ...Background:Metaplastic breast carcinoma(MBC)is a rare breast cancer subtype;most cases are triple‐negative breast cancers(TNBCs)and are poorly responsive to conventional systemic therapy.Few potential diagnostic and prognostic markers for distinguishing between metaplastic TNBC and nonmetaplastic TNBC have been discovered.We performed bioinformatic analysis to explore the underlying mechanism by which metaplastic TNBC differs from nonmetaplastic TNBC and provides potential pathogenic genes of metaplastic TNBC.Methods:Differentially expressed genes(DEGs)in metaplastic tumors and nonmetaplastic tumors from TNBC patients were screened using GSE165407.The GSE76275 data set and The Cancer Genome Atlas(TCGA)database were used to screen DEGs in TNBC and non‐TNBC.Metascape and DAVID were used for the Kyoto Encyclopedia of Genes and Genomes(KEGG)enrichment analysis and Gene Ontology(GO)analysis of DEGs.Online databases,including UALCAN,GEPIA,HPA,Breast Cancer Gene‐Expression Miner,and quantitative PCR and western blot,were used to examine KLK5 messenger RNA and protein expression in breast cancer.Analysis of KLK5‑associated genes was performed with TCGA data,and the LinkedOmics database was used to detect the genes co‐expressed with KLK5.STRING(Search Tool for the Retrieval of Interacting Genes)and Cytoscape were used to screen for hub genes.Kaplan‑Meier plotter was used for survival analysis.Results:KLK5 was identified among the DEGs in nonmetaplastic TNBC and metaplastic TNBC.The KLK5 gene was overexpressed in nonmetaplastic TNBC but downregulated in metaplastic TNBC.KEGG and GO analyses revealed that epithelial‐to‐mesenchymal transition was a pathogenic mechanism in metaplastic TNBC and an important pathway by which KLK5 and its associated genes DSG1and DSG3 influence metaplastic TNBC progression. Prognosis analysis showedthat only low expression of KLK5 in metaplastic TNBC had clinical significance.Conclusion: Our research indicated that KLK5 may be a pivotal moleculewith a key role in the mechanism of tumorigenesis in metaplastic TNBC.展开更多
Two-dimensional transition-metal dichalcogenides (WS2 and SnS2) have recently joined the family of energy storage materials (for lithium-ion batteries and supercapacitors) as a result of their favorable ion interc...Two-dimensional transition-metal dichalcogenides (WS2 and SnS2) have recently joined the family of energy storage materials (for lithium-ion batteries and supercapacitors) as a result of their favorable ion intercalation. So far, challenges in the synthesis of phase-pure WS2, restacking between WS2 nanosheets, low electronic conductivity, and the brittle nature of WS2, severely limit its use Li-ion battery application. Herein, we develop a facile low temperature solution sulfuration process to improve battery performance dramatically. The sulfuration process is demonstrated to be effective in converting WO3 impurities to WS2, and in repairing the sulfur vacancies, to improve cyclability and rate capability. Lithium-ion battery measurements demonstrate that the stable capacity of the WS2 anode could be enhanced by 48.4% via sulfuration reprocessing, i.e., from 381.7 to 566.8 rnAh/g at a relatively high current density of 0.8 A/g after 50 cycles. We further show that the sulfuration process can be readily extended to other dichalcogenides, and may provide a class of versatile electrode materials for lithium-ion batteries with improved electrochemical characteristics.展开更多
Peroxyacetyl nitrate(PA N)is one of the most important photochemical pollutants and has aroused much concern in China in recent decades.However,few studies described the long-term variations in PAN in China.In this st...Peroxyacetyl nitrate(PA N)is one of the most important photochemical pollutants and has aroused much concern in China in recent decades.However,few studies described the long-term variations in PAN in China.In this study,we continuously monitored the PAN,03 and NOx concentrations at a regional background site near Beijing from August 2015 to February 2019.Based on the observed concentrations and climate data,w e analyzed the seasonal PAN variations.The results revealed that the monthly mean PAN concentration ranged from 0.33-2.41 ppb,with an average value of 0.94 ppb.The PAN concentration exhibited a distinct seasonal variation,with high values in spring and low values in winter.After analyzing the corresponding meteorological data,we found that stronger ultraviolet(UV)radiation,a relatively longer lifetime and a higher background PAN concentration contributed to the high PAN concentrations in spring.In addition,with the utilization of the WRF-Chem(Weather Research and Forecasting with Chemistry)model,the cause of the extremely high PAN concentration in spring 2018 wa s determined.The model results demonstrated that an anomalously low pressure and the southwesterly winds in northern China might be the main causes of the increased PAN concentration in Beijing and its surrounding area in spring 2018.展开更多
Ground-basedMulti-AXis Differential Optical Absorption Spectroscopy(MAX-DOAS)measurements were performed at Shangdianzi(SDZ)regional atmospheric background station in northern China from March 2009 to February 2011.Th...Ground-basedMulti-AXis Differential Optical Absorption Spectroscopy(MAX-DOAS)measurements were performed at Shangdianzi(SDZ)regional atmospheric background station in northern China from March 2009 to February 2011.The tropospheric NO_2vertical column densities(VCDs)were retrieved to investigate the background condition of the Beijing–Tianjin–Hebei developed economic circle in China.The seasonal variation of mean NO_2tropospheric VCDs(VCD_(Trop))at SDZ is apparent,with the maximum(1.3×10^(16)molec/cm^2)in February and the minimum(3.5×10^(15)molec/cm^2)in August,much lower than those observed at the Beijing city center.The average daytime diurnal variations of NO_2VCD_(Trop )are rather consistent for all four seasons,presenting the minimum at noon and the higher values in the morning and evening.The largest and lowest amplitudes of NO_2VCD_(Trop)diurnal variation appear in winter and in summer,respectively.The diurnal pattern at SDZ station is similar to those at other less polluted stations,but distinct from the ones at the urban or polluted stations.Tropospheric NO_2VCDs at SDZ are strongly dependent on the wind,with the higher values being associated with the pollution plumes from Beijing city.Tropospheric NO_2VCDs derived from ground-based MAX-DOAS at SDZ show to be well correlated with corresponding OMI(Ozone Monitoring Instrument)satellite products with a correlation coefficient R=0.88.However,the OMI observations are on average higher than MAX-DOAS NO_2VCDs by a factor of 28%,probably due to the OMI grid cell partly covering the south of SDZ which is influenced more by the pollution plumes from the urban areas.展开更多
基金Supported by the China Scholarship Council (202205330024)National Key Research and Development Program of China (2017YFB0504002)+1 种基金National Science and Technology Infrastructure Platform Project (2017)Special Fund for Basic Scientific Research of Institute of Urban Meteorology (IUMKY201735)。
文摘Sunshine duration(SD) is adopted widely to study global dimming/brightening. However, long-term simultaneous measurements of SD and closely related impact factors require further analysis to elucidate how and why SD has varied during the past decades. In this study, a long-term(1958–2021) SD data series obtained from the Shangdianzi Global Atmosphere Watch(GAW) station in China was analyzed to detect linear trends, climatic jumps, and climatic periods in SD using linear fitting, the Mann–Kendall trend test, and the continuous wavelet transform method. Annual SD exhibited steady dimming(-67.3 h decade-1) before 2010, followed by a period of brightening(189.9 h decade-1)during 2011–2020. An abrupt jump in annual SD occurred in 1995, and the annual SD anomaly exhibited significant oscillation with ~3-yr periodicity during 1960–1978. Partial least squares analysis revealed that annual SD anomaly was associated with variations in relative humidity, gale days, cloud cover, and black carbon(BC). Further analysis of the clear-sky daily sunshine percentage(DSP) and simultaneous measurements of aerosol properties, including aerosol optical depth, aerosol extinction coefficient, single scattering albedo(SSA), BC, and total suspended particulates, suggested that variation in DSP was affected primarily by aerosol scattering and absorption. Furthermore, the hourly clear-sky SD at high aerosol loading was approximately 60% and 56% of that at middle and low aerosol loadings, respectively. The pattern of diurnal variation in clear-sky hourly SD, as well as the actual values, can be affected by the fine particulate concentration, aerosol extinction coefficient, and SSA.
基金National Natural Science Foundation of China,Grant/Award Number:82002816。
文摘Background:Metaplastic breast carcinoma(MBC)is a rare breast cancer subtype;most cases are triple‐negative breast cancers(TNBCs)and are poorly responsive to conventional systemic therapy.Few potential diagnostic and prognostic markers for distinguishing between metaplastic TNBC and nonmetaplastic TNBC have been discovered.We performed bioinformatic analysis to explore the underlying mechanism by which metaplastic TNBC differs from nonmetaplastic TNBC and provides potential pathogenic genes of metaplastic TNBC.Methods:Differentially expressed genes(DEGs)in metaplastic tumors and nonmetaplastic tumors from TNBC patients were screened using GSE165407.The GSE76275 data set and The Cancer Genome Atlas(TCGA)database were used to screen DEGs in TNBC and non‐TNBC.Metascape and DAVID were used for the Kyoto Encyclopedia of Genes and Genomes(KEGG)enrichment analysis and Gene Ontology(GO)analysis of DEGs.Online databases,including UALCAN,GEPIA,HPA,Breast Cancer Gene‐Expression Miner,and quantitative PCR and western blot,were used to examine KLK5 messenger RNA and protein expression in breast cancer.Analysis of KLK5‑associated genes was performed with TCGA data,and the LinkedOmics database was used to detect the genes co‐expressed with KLK5.STRING(Search Tool for the Retrieval of Interacting Genes)and Cytoscape were used to screen for hub genes.Kaplan‑Meier plotter was used for survival analysis.Results:KLK5 was identified among the DEGs in nonmetaplastic TNBC and metaplastic TNBC.The KLK5 gene was overexpressed in nonmetaplastic TNBC but downregulated in metaplastic TNBC.KEGG and GO analyses revealed that epithelial‐to‐mesenchymal transition was a pathogenic mechanism in metaplastic TNBC and an important pathway by which KLK5 and its associated genes DSG1and DSG3 influence metaplastic TNBC progression. Prognosis analysis showedthat only low expression of KLK5 in metaplastic TNBC had clinical significance.Conclusion: Our research indicated that KLK5 may be a pivotal moleculewith a key role in the mechanism of tumorigenesis in metaplastic TNBC.
基金This work was financially supported by the National Basic Research Program of China (No. 2013CB932903), the National Natural Science Foundation of China (Nos. 61205057 and 61203289), China Postdoctoral Science special Foundation (No. 2012T50488), Qing Lan Pro- ject, by the "1311 Talent Plan" Foundation of Nanjing University of Posts and Telecommunications.
文摘Two-dimensional transition-metal dichalcogenides (WS2 and SnS2) have recently joined the family of energy storage materials (for lithium-ion batteries and supercapacitors) as a result of their favorable ion intercalation. So far, challenges in the synthesis of phase-pure WS2, restacking between WS2 nanosheets, low electronic conductivity, and the brittle nature of WS2, severely limit its use Li-ion battery application. Herein, we develop a facile low temperature solution sulfuration process to improve battery performance dramatically. The sulfuration process is demonstrated to be effective in converting WO3 impurities to WS2, and in repairing the sulfur vacancies, to improve cyclability and rate capability. Lithium-ion battery measurements demonstrate that the stable capacity of the WS2 anode could be enhanced by 48.4% via sulfuration reprocessing, i.e., from 381.7 to 566.8 rnAh/g at a relatively high current density of 0.8 A/g after 50 cycles. We further show that the sulfuration process can be readily extended to other dichalcogenides, and may provide a class of versatile electrode materials for lithium-ion batteries with improved electrochemical characteristics.
基金This research is supported by the Beijing Natural Science Foundation(Grant No.8194078)National Key R&D Program of China(Grant No.2016YFC0201902)National Natural Science Foundation of China(Grant No.91744206)。
文摘Peroxyacetyl nitrate(PA N)is one of the most important photochemical pollutants and has aroused much concern in China in recent decades.However,few studies described the long-term variations in PAN in China.In this study,we continuously monitored the PAN,03 and NOx concentrations at a regional background site near Beijing from August 2015 to February 2019.Based on the observed concentrations and climate data,w e analyzed the seasonal PAN variations.The results revealed that the monthly mean PAN concentration ranged from 0.33-2.41 ppb,with an average value of 0.94 ppb.The PAN concentration exhibited a distinct seasonal variation,with high values in spring and low values in winter.After analyzing the corresponding meteorological data,we found that stronger ultraviolet(UV)radiation,a relatively longer lifetime and a higher background PAN concentration contributed to the high PAN concentrations in spring.In addition,with the utilization of the WRF-Chem(Weather Research and Forecasting with Chemistry)model,the cause of the extremely high PAN concentration in spring 2018 wa s determined.The model results demonstrated that an anomalously low pressure and the southwesterly winds in northern China might be the main causes of the increased PAN concentration in Beijing and its surrounding area in spring 2018.
基金supported by the National Natural Science Foundation of China (Nos. 41505123, 41330422, 41075095)the CAMS Development Funds of Science and Technology (Nos. 2018KJ001, 2018KJ002)
文摘Ground-basedMulti-AXis Differential Optical Absorption Spectroscopy(MAX-DOAS)measurements were performed at Shangdianzi(SDZ)regional atmospheric background station in northern China from March 2009 to February 2011.The tropospheric NO_2vertical column densities(VCDs)were retrieved to investigate the background condition of the Beijing–Tianjin–Hebei developed economic circle in China.The seasonal variation of mean NO_2tropospheric VCDs(VCD_(Trop))at SDZ is apparent,with the maximum(1.3×10^(16)molec/cm^2)in February and the minimum(3.5×10^(15)molec/cm^2)in August,much lower than those observed at the Beijing city center.The average daytime diurnal variations of NO_2VCD_(Trop )are rather consistent for all four seasons,presenting the minimum at noon and the higher values in the morning and evening.The largest and lowest amplitudes of NO_2VCD_(Trop)diurnal variation appear in winter and in summer,respectively.The diurnal pattern at SDZ station is similar to those at other less polluted stations,but distinct from the ones at the urban or polluted stations.Tropospheric NO_2VCDs at SDZ are strongly dependent on the wind,with the higher values being associated with the pollution plumes from Beijing city.Tropospheric NO_2VCDs derived from ground-based MAX-DOAS at SDZ show to be well correlated with corresponding OMI(Ozone Monitoring Instrument)satellite products with a correlation coefficient R=0.88.However,the OMI observations are on average higher than MAX-DOAS NO_2VCDs by a factor of 28%,probably due to the OMI grid cell partly covering the south of SDZ which is influenced more by the pollution plumes from the urban areas.