Formic and acetic acids are the most abundant gaseous organic acids and play the key role in the atmospheric chemistry.In iodine-adduct chemical ionizationmass spectrometry(CIMS),the low utilization efficiency of meth...Formic and acetic acids are the most abundant gaseous organic acids and play the key role in the atmospheric chemistry.In iodine-adduct chemical ionizationmass spectrometry(CIMS),the low utilization efficiency of methyl iodide and humidity interference are two major issues of the vacuum ultraviolet(VUV)lamp initiated CIMS for on-line gaseous formic and acetic acids analysis.In this work,we present a new CIMS based on VUV lamp,and the ion-molecular reactor is separated into photoionization and chemical ionization zones by a reducer electrode.Acetone was added to the photoionization zone,and the VUV photoionization acetone provided low-energy electrons for methyl iodide to generate I−,and the addition of acetone reduced the amount of methyl iodide by 2/3.In the chemical ionization zone,a headspace vial containing ultrapure water was added for humidity calibration,and the vial changes the sensitivity as a function of humidity from ambiguity to well linear correlation(R2>0.95).With humidity calibration,the CIMS can quantitatively measure formic and acetic acids in the humidity range of 0%-88%RH.In this mode,limits of detection of 10 and 50 pptv are obtained for formic and acetic acids,respectively.And the relative standard deviation(RSD)of quantitation stability for 6 days were less than 10.5%.This CIMS was successfully used to determine the formic and acetic acids in the underground parking and ambient environment of the Shandong University campus(Qingdao,China).In addition,we developed a simple model based formic acid concentration to assess vehicular emissions.展开更多
心力衰竭是一组复杂的临床综合征,是各种心脏疾病的严重表现或终末阶段。随着全球人口老龄化的加剧,其发病率和死亡率逐年增加。心肌细胞的自噬在心力衰竭的发生和发展中起着重要的作用。溶酶体相关膜蛋白2(lysosomal-associated membra...心力衰竭是一组复杂的临床综合征,是各种心脏疾病的严重表现或终末阶段。随着全球人口老龄化的加剧,其发病率和死亡率逐年增加。心肌细胞的自噬在心力衰竭的发生和发展中起着重要的作用。溶酶体相关膜蛋白2(lysosomal-associated membrane protein 2,LAMP-2)基因编码的蛋白质是维持正常溶酶体功能的关键因子。近年来的研究发现,LAMP-2在心力衰竭中的异常表达与心脏功能下降密切相关。本综述将概述LAMP-2基因的结构和功能,并综合分析LAMP-2在心力衰竭中的研究进展,为深入理解和治疗心力衰竭提供理论基础。展开更多
基金supported by the National Special Fund for the Development of Major Research Equipment and Instrument(No.2020YFF01014503)the Young Taishan Scholars(No.tsqn201909039)the College 20 Project fromJi Nan Science&Technology Bureau(No.2021GXRC058).
文摘Formic and acetic acids are the most abundant gaseous organic acids and play the key role in the atmospheric chemistry.In iodine-adduct chemical ionizationmass spectrometry(CIMS),the low utilization efficiency of methyl iodide and humidity interference are two major issues of the vacuum ultraviolet(VUV)lamp initiated CIMS for on-line gaseous formic and acetic acids analysis.In this work,we present a new CIMS based on VUV lamp,and the ion-molecular reactor is separated into photoionization and chemical ionization zones by a reducer electrode.Acetone was added to the photoionization zone,and the VUV photoionization acetone provided low-energy electrons for methyl iodide to generate I−,and the addition of acetone reduced the amount of methyl iodide by 2/3.In the chemical ionization zone,a headspace vial containing ultrapure water was added for humidity calibration,and the vial changes the sensitivity as a function of humidity from ambiguity to well linear correlation(R2>0.95).With humidity calibration,the CIMS can quantitatively measure formic and acetic acids in the humidity range of 0%-88%RH.In this mode,limits of detection of 10 and 50 pptv are obtained for formic and acetic acids,respectively.And the relative standard deviation(RSD)of quantitation stability for 6 days were less than 10.5%.This CIMS was successfully used to determine the formic and acetic acids in the underground parking and ambient environment of the Shandong University campus(Qingdao,China).In addition,we developed a simple model based formic acid concentration to assess vehicular emissions.
文摘心力衰竭是一组复杂的临床综合征,是各种心脏疾病的严重表现或终末阶段。随着全球人口老龄化的加剧,其发病率和死亡率逐年增加。心肌细胞的自噬在心力衰竭的发生和发展中起着重要的作用。溶酶体相关膜蛋白2(lysosomal-associated membrane protein 2,LAMP-2)基因编码的蛋白质是维持正常溶酶体功能的关键因子。近年来的研究发现,LAMP-2在心力衰竭中的异常表达与心脏功能下降密切相关。本综述将概述LAMP-2基因的结构和功能,并综合分析LAMP-2在心力衰竭中的研究进展,为深入理解和治疗心力衰竭提供理论基础。
