We conducted a field campaign to investigate the chemical composition,sources,and light absorption of submicron aerosols(PM_(1))from early 2022 in Nanjing,China.The average concentration of PM_(1) was 31μg m^(−3),org...We conducted a field campaign to investigate the chemical composition,sources,and light absorption of submicron aerosols(PM_(1))from early 2022 in Nanjing,China.The average concentration of PM_(1) was 31μg m^(−3),organics(33%)constituted the largest fraction,followed by nitrate(30%),sulfate(18%),ammonium(15%),chloride(3%),and rBC(2%).Four organic aerosol(OA)subcomponents were identified,including two primary OA(POA)and two secondary OA(SOA).The less-oxidized SOA(LO-OOA)contributes the most to the total OA mass(59%).LO-OOA is tightly correlated with the tracer ion C_(2)H_(4)O_(2)^(+)from levoglucosan,and another aged biomass-burning derived species,K_(3)SO_(4)^(+),suggesting it was likely influenced by aged biomass-burning OA.Our study also revealed that fireworks during the Spring Festival have a detrimental impact on air quality,contributing to secondary formation and accumulation under static winter meteorological conditions,prolonging the pollution duration.Also,LO-OOA was found to have the strongest light-absorbing ability.Our results highlight that the light absorption of LO-OOA can mainly be attributed to the C_(x)H_(y)N^(+) family,increased with the double-bond equivalent value.The more-oxidized SOA(MO-OOA)exhibited a negligible light absorption and was strongly correlated with daytime photochemical processes,implying a light-bleaching effect.This study enhances our understanding of the regional contribution of biomass combustion and fireworks to PM_(1) pollution in Nanjing,a typical megacity in the Yangtze River Delta region,during winter,aiding in the development of strategies for long-term air quality improvement in the region.展开更多
随着数字音源的普及,数模转换器(Digital to Analog Converter, DAC)成为音频设备中不可或缺的元件,其精度往往决定着整个系统的信号保真度。基于此,利用噪声整形技术对用于高精度音频DAC的Sigma-Delta调制器进行设计和现场可编程门阵列...随着数字音源的普及,数模转换器(Digital to Analog Converter, DAC)成为音频设备中不可或缺的元件,其精度往往决定着整个系统的信号保真度。基于此,利用噪声整形技术对用于高精度音频DAC的Sigma-Delta调制器进行设计和现场可编程门阵列(Field Programmable Gate Array, FPGA)实现。通过搭建测试系统,测试结果表明,所设计的Sigma-Delta调制器在输入信号为1 411.2 kHz采样频率、1 kHz频率、0 dBFS(Full Scale)幅度的正弦信号条件下,其输出信噪比(Signal to Noise Ratio, SNR)可达107.4 dB;当输入信号频率在音频频带内时(输入信号幅度为0dBFS),其输出SNR稳定保持在104 dB以上;并可用于WAV音乐播放器中。展开更多
BACKGROUND Hepatitis delta virus(HDV)infection is the most severe form of chronic viral hepatitis,yet sex-based clinical differences remain poorly defined.Understanding these differences may inform disease management ...BACKGROUND Hepatitis delta virus(HDV)infection is the most severe form of chronic viral hepatitis,yet sex-based clinical differences remain poorly defined.Understanding these differences may inform disease management and guide research.AIM To investigate sex-related differences in demographic and clinical characteristics of patients with chronic HDV infection in a nationwide,real-world Italian setting.METHODS We analyzed demographic,clinical,and virological data from 513 hepatitis B surface antigen/anti-HDV-positive patients,consecutively enrolled between 2019 and 2024,across 58 liver clinics in the Italian PITER HDV cohort.A propensity score-weighted logistic regression model evaluated the association between sex and cirrhosis and/or hepatocellular carcinoma.RESULTS Among 513 patients(61.6%male),median age(56.0 years)and age distribution were similar by sex(P=0.41).Cirrhosis was frequent:73.4%vs 66.0%(anti-HDV-positive)and 77.8%vs 74.2%(HDV RNA-positive)in males and females,respectively.HDV RNA levels were comparable(P=0.93).The highest proportion of females with cirrhosis(33.8%)was in the 56-60-year group,similar to males(34.9%).Among patients with cirrhosis aged≤40 years,females,(80.9%of whom of non-Italian origin),were more represented than males(16.1%vs 6.5%respectively,P<0.05).Male sex was associated with cirrhosis(odds ratio=1.85;95%confidence interval:1.004-3.40).Among HDV RNA-positive patients,males more often had hepatocellular carcinoma,elevated gammaglutamyl transpeptidase,alcohol use,diabetes,hypertension,steatotic liver disease,and hepatitis C virus/human immunodeficiency virus coinfection.Interferon eligibility was similar.CONCLUSION HDV-infected females develop cirrhosis earlier,without liver disease cofactors,while males show advanced liver disease with multiple cofactors.Tailored care for young migrant women and cofactor-guided management for men may improve HDV outcomes,promoting equity.展开更多
A macro-tidal tropical estuary with high fluvial discharge is characterized by both fragility and remarkable dynamism.This study utilizes the Salween River Delta(SRD)as a case example to examine the interplay between ...A macro-tidal tropical estuary with high fluvial discharge is characterized by both fragility and remarkable dynamism.This study utilizes the Salween River Delta(SRD)as a case example to examine the interplay between morphology and vegetation under similar tidal conditions.Our analysis of correlations and inferences revealed several significant trends in the SRD:(1)an overall expansion of land area and intertidal vegetation,with the most pronounced changes occurring in the eastern sector;(2)the predominance of river discharge influencing the southwestern and northern sectors,contrasted with the primary impact of storm surges in the eastern sector;and(3)three distinct causal relationships among estuarine morphology,vegetation,storm surges,and river discharge:a direct model where river discharge shapes estuarine morphology,a progressive model in which river discharge affects vegetation distribution,subsequently influencing estuarine morphology,and a hybrid model where storm surges directly impact vegetation and indirectly modify its distribution through changes in estuarine morphology.The stability of sediment supply and the role of intertidal vegetation are crucial for the continuous seaward advance,providing a vital foundation for the protection and development of estuarine deltas.展开更多
基金support from the Natural Science Foundation of Jiangsu Province(Grant No.BK20240036)the National Natural Science Foundation of China(Grant Nos.U24A20515,22276099,and 22361162668)Guangxi Key Research and Development Program,China(Grant No.Guike AB24010074)。
文摘We conducted a field campaign to investigate the chemical composition,sources,and light absorption of submicron aerosols(PM_(1))from early 2022 in Nanjing,China.The average concentration of PM_(1) was 31μg m^(−3),organics(33%)constituted the largest fraction,followed by nitrate(30%),sulfate(18%),ammonium(15%),chloride(3%),and rBC(2%).Four organic aerosol(OA)subcomponents were identified,including two primary OA(POA)and two secondary OA(SOA).The less-oxidized SOA(LO-OOA)contributes the most to the total OA mass(59%).LO-OOA is tightly correlated with the tracer ion C_(2)H_(4)O_(2)^(+)from levoglucosan,and another aged biomass-burning derived species,K_(3)SO_(4)^(+),suggesting it was likely influenced by aged biomass-burning OA.Our study also revealed that fireworks during the Spring Festival have a detrimental impact on air quality,contributing to secondary formation and accumulation under static winter meteorological conditions,prolonging the pollution duration.Also,LO-OOA was found to have the strongest light-absorbing ability.Our results highlight that the light absorption of LO-OOA can mainly be attributed to the C_(x)H_(y)N^(+) family,increased with the double-bond equivalent value.The more-oxidized SOA(MO-OOA)exhibited a negligible light absorption and was strongly correlated with daytime photochemical processes,implying a light-bleaching effect.This study enhances our understanding of the regional contribution of biomass combustion and fireworks to PM_(1) pollution in Nanjing,a typical megacity in the Yangtze River Delta region,during winter,aiding in the development of strategies for long-term air quality improvement in the region.
基金Supported by the Investigator Sponsored Research Grant from Gilead Sciences,No.IN-IT-980-6816the Fondazione Italiana per la Ricerca sul Cancro(AIRC),No.IG 2020 ID 24858.
文摘BACKGROUND Hepatitis delta virus(HDV)infection is the most severe form of chronic viral hepatitis,yet sex-based clinical differences remain poorly defined.Understanding these differences may inform disease management and guide research.AIM To investigate sex-related differences in demographic and clinical characteristics of patients with chronic HDV infection in a nationwide,real-world Italian setting.METHODS We analyzed demographic,clinical,and virological data from 513 hepatitis B surface antigen/anti-HDV-positive patients,consecutively enrolled between 2019 and 2024,across 58 liver clinics in the Italian PITER HDV cohort.A propensity score-weighted logistic regression model evaluated the association between sex and cirrhosis and/or hepatocellular carcinoma.RESULTS Among 513 patients(61.6%male),median age(56.0 years)and age distribution were similar by sex(P=0.41).Cirrhosis was frequent:73.4%vs 66.0%(anti-HDV-positive)and 77.8%vs 74.2%(HDV RNA-positive)in males and females,respectively.HDV RNA levels were comparable(P=0.93).The highest proportion of females with cirrhosis(33.8%)was in the 56-60-year group,similar to males(34.9%).Among patients with cirrhosis aged≤40 years,females,(80.9%of whom of non-Italian origin),were more represented than males(16.1%vs 6.5%respectively,P<0.05).Male sex was associated with cirrhosis(odds ratio=1.85;95%confidence interval:1.004-3.40).Among HDV RNA-positive patients,males more often had hepatocellular carcinoma,elevated gammaglutamyl transpeptidase,alcohol use,diabetes,hypertension,steatotic liver disease,and hepatitis C virus/human immunodeficiency virus coinfection.Interferon eligibility was similar.CONCLUSION HDV-infected females develop cirrhosis earlier,without liver disease cofactors,while males show advanced liver disease with multiple cofactors.Tailored care for young migrant women and cofactor-guided management for men may improve HDV outcomes,promoting equity.
基金National Natural Science Foundation of China,No.41906148,No.42271086Rejuvenating Yunnan Talents Support Plan Young Talent Program,No.XDYC-QNRC-2023-0322。
文摘A macro-tidal tropical estuary with high fluvial discharge is characterized by both fragility and remarkable dynamism.This study utilizes the Salween River Delta(SRD)as a case example to examine the interplay between morphology and vegetation under similar tidal conditions.Our analysis of correlations and inferences revealed several significant trends in the SRD:(1)an overall expansion of land area and intertidal vegetation,with the most pronounced changes occurring in the eastern sector;(2)the predominance of river discharge influencing the southwestern and northern sectors,contrasted with the primary impact of storm surges in the eastern sector;and(3)three distinct causal relationships among estuarine morphology,vegetation,storm surges,and river discharge:a direct model where river discharge shapes estuarine morphology,a progressive model in which river discharge affects vegetation distribution,subsequently influencing estuarine morphology,and a hybrid model where storm surges directly impact vegetation and indirectly modify its distribution through changes in estuarine morphology.The stability of sediment supply and the role of intertidal vegetation are crucial for the continuous seaward advance,providing a vital foundation for the protection and development of estuarine deltas.
