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Development of an automatic measurement system using atmospheric pressure photoionization ultrahigh-resolution mass spectrometry and application for on-line analysis of particulate matter

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Journal of Environmental Sciences 2024年第4期138卷 516-530页

作者： Yayuan Dong ranran Liu Ling Xie Xiaole Pan Yele sun Lin Wu ZifaWang State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China Center for Excellence in Regional Atmospheric Environment Chinese Academy of SciencesInstitute of Urban EnvironmentXiamen 361021China

On-line chemical characterization of atmospheric particulate matter(PM)with soft ionization technique and ultrahigh-resolution Mass Spectrometry(UHRMS)provides molecular information of organic constituents in real time.Here we describe the development and application of an automatic measurement system that incorporates PM_(2.5)sampling,thermal desorption,atmospheric pressure photoionization,and UHRMS analysis.Molecular formulas of detected organic compounds were deducted from the accurate(±10 ppm)molecular weights obtained at a mass resolution of 100,000,allowing the identification of small organic compounds in PM_(2.5).Detection efficiencies of 28 standard compounds were determined and we found a high sensitivity and selectivity towards organic amines with limits of detection below 10 pg.As a proof of principle,PM_(2.5)samples collected off-line in winter in the urban area of Beijing were analyzed using the Ionization Module and HRMS of the system.The automatic system was then applied to conduct on-line measurements during the summer time at a time resolution of 2 hr.The detected organic compounds comprised mainly CHON and CHN compounds below 350 m/z.Pronounced seasonal variations in elemental composition were observed with shorter carbon backbones and higher O/C ratios in summer than that in winter.This result is consistent with stronger photochemical reactions and thus a higher oxidation state of organics in summer.Diurnal variation in signal intensity of each formula provides crucial information to reveal its source and formation pathway.In summary,the automatic measurement system serves as an important tool for the on-line characterization and identification of organic species in PM_(2.5).

关键词： PM_(2.5) Chemical composition On-line measurement technique High resolution mass spectrometry

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Policy Iteration for Optimal Control of Discrete-Time Time-Varying Nonlinear Systems

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IEEE/CAA Journal of Automatica Sinica 2023年第3期10卷 781-791页

作者： Guangyu Zhu Xiaolu Li ranran sun Yiyuan Yang Peng Zhang Beijing Research Center of Urban Traffic Information Sensing and Service Technologies Key Laboratory of Transport Industry of Big Data Application Technologies for Comprehensive Transport Beijing Jiaotong UniversityBeijing 100044China Transport Planning and Research Institute Ministry of TransportChinaBeijing 100028China

Aimed at infinite horizon optimal control problems of discrete time-varying nonlinear systems,in this paper,a new iterative adaptive dynamic programming algorithm,which is the discrete-time time-varying policy iteration(DTTV)algorithm,is developed.The iterative control law is designed to update the iterative value function which approximates the index function of optimal performance.The admissibility of the iterative control law is analyzed.The results show that the iterative value function is non-increasingly convergent to the Bellman-equation optimal solution.To implement the algorithm,neural networks are employed and a new implementation structure is established,which avoids solving the generalized Bellman equation in each iteration.Finally,the optimal control laws for torsional pendulum and inverted pendulum systems are obtained by using the DTTV policy iteration algorithm,where the mass and pendulum bar length are permitted to be time-varying parameters.The effectiveness of the developed method is illustrated by numerical results and comparisons.

关键词： Adaptive critic designs adaptive dynamic programming approximate dynamic programming optimal control policy iteration time-varying

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A polygalacturonase gene OsPG1 modulates water homeostasis in rice

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The Crop Journal 2024年第1期12卷 79-91页

作者： Qinwen Zou ranran Tu Jiajun Wu Tingting Huang Zhihao sun Zheyan Ruan Hongyu Cao Shihui Yang Xihong Shen Guanghua He Hong Wang Rice Research Institute Key Laboratory of Application and Safety Control of Genetically Modified CropsAcademy of Agricultural SciencesSouthwest UniversityChongqing 400715China State Key Laboratory of Rice Biology and Breeding Key Laboratory for Zhejiang Super Rice ResearchChina National Center for Rice ImprovementChina National Rice Research InstituteHangzhou 311401ZhejiangChina

A dynamic plant architecture is the basis of plant adaptation to changing environments.Although many genes regulating leaf rolling have been identified,genes directly associated with water homeostasis are largely unknown.Here,we isolated a rice mutant,dynamic leaf rolling 1(dlr1),characterized by‘leaf unfolding in the morning-leaf rolling at noon-leaf unfolding in the evening’during a sunny day.Water content was decreased in rolled leaves and water sprayed on leaves caused reopening,indicating that in vivo water deficiency induced the leaf rolling.Map-based cloning and expression tests demonstrated that an A1400G single base mutation in Oryza sativa Polygalacturonase 1(OsPG1)/PHOTO-SENSITIVE LEAF ROLLING 1(PSL1)was responsible for the dynamic leaf rolling phenotype in the dlr1 mutant.OsPG1 encodes a polygalacturonase,one of the main enzymes that degrade demethylesterified homogalacturonans in plant cell walls.OsPG1 was constitutively expressed in various tissues and was enriched in stomata.Mutants of the OsPG1 gene exhibited defects in stomatal closure and decreased stomatal density,leading to reduced transpiration and excessive water loss under specific conditions,but had normal root development.Further analysis revealed that mutation of OsPG1 led to reduced pectinase activity in the leaves and increased demethylesterified homogalacturonans in guard cells.Our findings reveal a mechanism by which OsPG1 modulates water homeostasis to control dynamic leaf rolling,providing insights for plants to adapt to environmental variation.

关键词： Photosynthesis Stomata Transpiration Leaf rolling

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A rice exocyst subunit gene SEC3A is required for anther dehiscence

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The Crop Journal 2024年第3期12卷 938-943页

作者： ranran Tu Hong Wang Zhihao sun Qinwen Zou Jiajun Wu Duo Wu Nan Wang Guanghua He Rice Research Institute Key Laboratory of Application and Safety Control of Genetically Modified CropsAcademy of Agricultural SciencesSouthwest UniversityChongqing 400715China

Anther dehiscence controls optimal interaction between pollen and stigma,thereby determining the successful sexual reproduction.The regulators or mechanisms of this process remain elusive.Here,two CRISPR/Cas9 mutants of a rice exocyst subunit gene SEC3A,sec3a-1 and sec3a-2,showed anther indehiscence at anthesis and male sterility at maturity.Pollen viability and germination in the mutants were partly defective,whereas their female gametes undergone a normal development.Hybrid or self-pollinated seeds could be produced by artificial pollination,suggesting potential use of a weak sec3a mutant as a female line during hybrid breeding.SEC3A is widely expressed in various tissues,including anther walls.Further results showed an excessive IAA accumulation and no endothecium lignification in sec3a-1/2 anthers.Our findings suggest that SEC3A appears to regulate anther dehiscence by modulating auxin signaling,providing insights into regulation of anther dehiscence and function of exocyst in plants.

关键词： Rice Male sterility Anther dehiscence Exocyst SEC3A

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Lanthanide-based ratiometric luminescence nanothermometry

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Nano Research 2023年第2期16卷 2949-2967页

作者： Mochen Jia Xu Chen ranran sun Di Wu Xinjian Li Zhifeng Shi Guanying Chen Chongxin Shan Key Laboratory of Materials Physics of Ministry of Education School of Physics and MicroelectronicsZhengzhou UniversityZhengzhou 450052China MIIT Key Laboratory of Critical Materials Technology for New Energy Conversion and Storage School of Chemistry and Chemical Engineering&Key Laboratory of Micro-systems and Micro-structuresMinistry of EducationHarbin Institute of TechnologyHarbin 150001China

Luminescent nanothermometry can precisely and remotely measure the internal temperature of objects at nanoscale precision,which,therefore,has been placed at the forefront of scientific attention.In particular,due to the high photochemical stability,low toxicity,rich working mechanisms,and superior thermometric performance,lanthanide-based ratiometric luminesencent thermometers are finding prevalent uses in integrated electronics and optoelectronics,property analysis of in-situ tracking,biomedical diagnosis and therapy,and wearable e-health monitoring.Despite recent progresses,it remains debate in terms of the underlying temperature-sensing mechanisms,the quantitative characterization of performance,and the reliability of temperature readouts.In this review,we show the origin of thermal response luminescence,rationalize the ratiometric scheme or thermometric mechanisms,delve into the problems in the characterization of thermometric performance,discuss the universal rules for the quantitative comparison,and showcase the cutting-edge design and emerging applications of lanthanide-based ratiometric thermometers.Finally,we cast a look at the challenges and emerging opportunities for further advances in this field.

关键词： luminescent nanothermometry lanthanide ions ratiometric thermometers thermal imaging

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Crocus genome reveals the evolutionary origin of crocin biosynthesis

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Acta Pharmaceutica Sinica B 2024年第4期14卷 1878-1891页

作者： Zhichao Xu Shanshan Chen Yalin Wang Ya Tian Xiaotong Wang Tianyi Xin Zishan Li Xin Hua Shengnan Tan Wei sun Xiangdong Pu Hui Yao ranran Gao Jingyuan Song Key Lab of Chinese Medicine Resources Conservation State Administration of Traditional Chinese Medicine of the People's Republic of ChinaInstitute of Medicinal Plant DevelopmentChinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100193China State Key Laboratory of Basis and New Drug Development of Natural and Nuclear Drugs Engineering Research Center of Chinese Medicine ResourceMinistry of EducationBeijing 100193China College of Life Science Northeast Forestry UniversityHarbin 150040China Key Laboratory of Beijing for Identification and Safety Evaluation of Chinese Medicine China Academy of Chinese Medical SciencesInstitute of Chinese Materia MedicaBeijing 100700China Analysis and Testing Center of Northeast Forestry University Harbin 150040China School of Pharmacy Anhui Medical UniversityInflammation and Immune Mediated Diseases Laboratory of Anhui ProvinceHefei 230032China

Crocus sativus (saffron) is a globally autumn-flowering plant, and its stigmas are the most expensive spice and valuable herb medicine. Crocus specialized metabolites, crocins, are biosynthesized in distant species, Gardenia (eudicot) and Crocus (monocot), and the evolution of crocin biosynthesis remains poorly understood. With the chromosome-level Crocus genome assembly, we revealed that two rounds of lineage-specific whole genome triplication occurred, contributing important roles in the production of carotenoids and apocarotenoids. According to the kingdom-wide identification, phylogenetic analysis, and functional assays of carotenoid cleavage dioxygenases (CCDs), we deduced that the duplication, site positive selection, and neofunctionalization of Crocus-specific CCD2 from CCD1 members are responsible for the crocin biosynthesis. In addition, site mutation of CsCCD2 revealed the key amino acids, including I143, L146, R161, E181, T259, and S292 related to the catalytic activity of zeaxanthin cleavage. Our study provides important insights into the origin and evolution of plant specialized metabolites, which are derived by duplication events of biosynthetic genes.

关键词： Crocus sativus WGT Crocin biosynthesis Carotenoids Apocarotenoids CCDs

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枸杞植物化学成分调节肠道菌群及相关生理功能的研究进展

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浙江大学学报（农业与生命科学版） 2024年第1期50卷 25-34页

作者：毕冉冉赵圆孙玉敬浙江工业大学食品科学与工程学院浙江杭州310014

枸杞含有多种营养和活性组分,具有一定的食用和药用价值。过去的研究发现,枸杞提取物具有调节免疫、抗肿瘤、抗癌等多种生物活性。最新的研究发现枸杞及其提取物还具有肠道菌群调节功能。本文对宁夏枸杞(红枸杞)和黑果枸杞果实中的枸杞... 详细信息

枸杞含有多种营养和活性组分,具有一定的食用和药用价值。过去的研究发现,枸杞提取物具有调节免疫、抗肿瘤、抗癌等多种生物活性。最新的研究发现枸杞及其提取物还具有肠道菌群调节功能。本文对宁夏枸杞(红枸杞)和黑果枸杞果实中的枸杞多糖、花色苷、甜菜碱、酚酸、黄酮类化合物、类胡萝卜素等植物化学成分进行了介绍,详述了枸杞全果及其提取物对肠道菌群及相关生理功能的影响,并对未来的研究方向进行了展望。

关键词：宁夏枸杞(红枸杞) 黑果枸杞植物化学成分肠道菌群

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The successful treatment for cardiac tamponade during radiofrequency ablation of hepatocellular carcinoma

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Hepatobiliary & Pancreatic Diseases International 2019年第1期18卷 90-92页

作者： Chen Xue Zhigang Ren Xiaobo Hu Yuting He ranran sun Juan Li Guangying Cui Zujiang Yu Department of Infectious Disease The First Affiliated Hospital of Zhengzhou University Precision Medicine Center The First Affiliated Hospital of Zhengzhou University

To the Editor:Hepatocellular carcinoma(HCC)is the second most common cause of cancer-related death worldwide[1].Repeated liver resection remains a valid and safe curative therapy option for recurrent HCC in a minority of patients,because of multifocal intrahepatic or extra-hepatic recurrence and tumors in unresectable locations[2].HCC nodules less than 3 cm located in the hepatic dome beneath the diaphragm may represent one of the most difficult sites for resection[3].Therefore,some local invasive therapies,such as radiofrequency ablation(RFA),microwave ablation,transarterial chemoembolization(TACE)and laser hyperthermia,have been developed and applied in clinical HCC treatment[4].RFA has high frequency energy which heats the surrounding tissues and causes severe complications such as acute massive hemorrhage,thermal injury to viscera,pneumothorax and cardiac tamponade[5].

关键词： hepatocellular HCC

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重复经颅磁刺激对脑卒中后上肢运动功能影响的功能性近红外光谱研究

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中华物理医学与康复杂志 2024年第2期46卷 123-128页

作者：李响张洪蕊曹海杰宋慧杰袁冉冉孙亚鲁济宁医学院附属医院康复医学科济宁272000

目的:近红外脑功能成像(fNIRS)技术的检测下,观察重复经颅磁刺激(rTMS)对脑卒中患者上肢运动功能和大脑皮质激活的影响。方法:将符合纳入标准的60例脑卒中患者随机分为干预组和对照组,每组30例。所有患者均给予常规的康复训练(包括药物... 详细信息

目的:近红外脑功能成像(fNIRS)技术的检测下,观察重复经颅磁刺激(rTMS)对脑卒中患者上肢运动功能和大脑皮质激活的影响。方法:将符合纳入标准的60例脑卒中患者随机分为干预组和对照组,每组30例。所有患者均给予常规的康复训练(包括药物治疗、偏瘫肢体综合训练、物理因子疗法等),每日治疗60 min,6 d/周,持续4周。对照组在常规康复训练的基础上给予假rTMS刺激,干预组在此基础上给予rTMS刺激,每日1次,每次15 min,6 d/周,持续4周。分别于治疗前和治疗4周后(治疗后),采用Fugl-Meyer上肢运动功能评分量表(FMA-UE)对2组患者的上肢运动功能进行评估,采用fNIRS技术检测并比较治疗前后2组患者的前额叶皮质(PFC)、运动皮质(MC)和初级躯体感觉皮质(PSC)的激活程度(β值),并进一步分析和比较不同病变脑区的β值。采用Pearson相关性分析法进行FMA-UE评分变量与β值变量的相关性分析。结果:①治疗前,干预组和对照组患者的FMA-UE评分[(32.96±3.24)和(32.03±4.11)分]组间差异无统计学意义( P>0.05);治疗后,2组患者的FMA-UE评分[(42.33±3.80)和(39.23±4.77)分]均较组内治疗前明显增加( P0.05)。治疗后,干预组CH27和CH13的β值较对照组明显提高( P<0.05);在左侧病变脑区患者中,干预组治疗后的CH27和CH13的β值较对照组明显提高( P<0.05),且左侧干预组CH13的β值与组内治疗前比较,差异有统计学意义( P<0.05)。③Pearson相关性分析结果显示,干预组患者的FMA-UE评分变量与CH27及CH13的β值变量呈中度相关( P<0.05),对照组的FMA-UE评分变量与CH27的β值变量呈低度相关( P<0.05)。结论:rTMS有利于激活左侧病变脑区的兴奋性,提高患者的上肢运动功能,且上肢运动功能的改善与左前额叶皮质(LPFC)、左初级躯体感觉皮质(LPSC)的激活具有相关性。

关键词：重复经颅磁刺激近红外脑功能成像技术脑卒中

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河套盆地临河坳陷兴隆构造带临河组超压成因及演化特征

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天然气地球科学 2024年第4期35卷 661-675页

作者：孙越谢佩宇张凤奇陈树光李永新关铭周然然张洁西安石油大学地球科学与工程学院陕西西安710065 西安石油大学陕西省油气成藏地质学重点实验室陕西西安710065 中国石油华北油田分公司勘探开发研究院河北任丘062552 中国石油勘探开发研究院赵文智院士工作室北京100083

河套盆地临河坳陷兴隆构造带不同构造部位超压分布差异大,演化过程复杂。根据测井、录井以及实测地层压力等资料,利用改进的超压识别图版和数值模拟方法及实际地质条件,综合识别研究区临河组超压成因,进一步定量评价不同成因超压的贡献... 详细信息

河套盆地临河坳陷兴隆构造带不同构造部位超压分布差异大,演化过程复杂。根据测井、录井以及实测地层压力等资料,利用改进的超压识别图版和数值模拟方法及实际地质条件,综合识别研究区临河组超压成因,进一步定量评价不同成因超压的贡献率及演化过程,明确不同构造带超压差异分布规律。结果表明:①研究区临河组超压强度从构造高部位到洼槽区有逐渐增大的趋势,其临河组烃源岩层超压成因主要是生烃作用和欠压实作用,储层中的超压成因主要为超压传递作用和欠压实作用;②研究区不同岩性地层各机制超压贡献构成差异较大,生烃增压对研究区临河组烃源岩层总超压的贡献率为56.68%~89.30%,超压传递增压对研究区临河组储层总超压的贡献率为63.80%~96.09%;③距今5.3 Ma,研究区临河组烃源岩和储层中欠压实增压开始形成,之后平缓增加至现今,烃源岩中生烃增压和储层中超压传递增压分别自5.3 Ma和3 Ma以来开始形成并快速增大至现今。该研究既有助于深化认识临河坳陷深层超压形成机制,又可指导该地区后期的油气勘探工作。

关键词：生烃增压超压传递盆地模拟压力演化临河坳陷

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