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A dopant-assisted iodide-adduct chemical ionization time-of-flight mass spectrometer based on VUV lamp photoionization for atmospheric low-molecular-weight organic acids analysis

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Journal of Environmental Sciences 2025年第3期149卷 500-511页

作者： Yonglei Zhang Ruidong Liu Mei Li Yingzhe guo Jichuang Kong Keyong Hou Environment Research Institute Shandong UniversityQingdao 266237China

Formic and acetic acids are the most abundant gaseous organic acids and play the key role in the atmospheric *** 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 *** 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 *** 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/*** 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%*** this mode,limits of detection of 10 and 50 pptv are obtained for formic and acetic acids,*** 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.

关键词： Formic acid Acetic acid Vacuum ultraviolet(VUV)lamp photoionization(PI) Chemical ionization(CI) Time-of-flight mass spectrometry (TOFMS) Trace gases measurement

Metrological traceable calibration of organic carbon and elemental carbon based on laboratory-generated reference materials

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Journal of Environmental Sciences 2025年第3期149卷 524-534页

作者： Yue Liu Junjie Liu Ji Xiao Jing Ye Lixu guo Caiqing Yan Center for Environmental Metrology National Institute of Metrology ChinaBeijing 100029China College of Chemistry and Chemical Engineering Taiyuan University of TechnologyTaiyuan 030024China Environment Research Institute Shandong UniversityQingdao 266237China

Carbonaceous aerosol,including organic carbon(OC)and elemental carbon(EC),has significant influence on human health,air quality and climate *** measurement of carbonaceous aerosol is essential to reduce the uncertainty of radiative forcing estimation and source *** accurate separation of OC and EC is controversial due to the charring of ***,the development of reference materials(RM)for the validation of OC/EC separation is an important basis for further *** RMs were mainly based on ambient air sampling,which could not provide traceability of OC and EC *** develop traceable RMs with known OC/EC contents,our study applied an improved aerosol generation and mixing technique,providing uniform deposition of particles on quartz *** generate OC aerosol with similar pyrolytic property of ambient aerosol,both water soluble organic carbon(WSOC)and water insoluble organic carbon(WIOC)were used,and amorphous carbon was selected for EC *** RMs were analyzed using different *** homogeneity within the filter was validated,reaching below 2%.The long-term stability of RMs has been validated with RSD ranged from 1.7%–3.2%.Good correlationwas observed between nominal concentration of RMswithmeasured concentration by two protocols,while the difference of EC concentration was within 20%.The results indicated that the newly developed RMs were acceptable for the calibration of OC and EC,which could improve the accuracy of carbonaceous aerosol ***,the laboratory-generated EC-RMs could be suitable for the calibration of equivalent BC concentration by Aethalometers.

关键词： Carbonaceous aerosol Split point Reference material Laboratory-generated Traceability

Study on the off situ reconstruction of the core neutron field based on dual-task hybrid network architecture

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Nuclear Science and Techniques 2025年第1期36卷 175-191页

作者： Pei Cao Hui Ding Cheng-Long Cao Zi-Hui Yang guo-Min Sun School of Artificial Intelligence and Big Data Hefei UniversityHefei 230001China College of Electronic Engineering National University of Defense TechnologyHefei 230001China Institute of Nuclear Energy Safety Technology HFIPSChinese Academy of SciencesHefei 230027China

The off situ accurate reconstruction of the core neutron field is an important step in realizing real-time reactor *** existing off situ reconstruction method of the neutron field is only applicable to cases wherein a single region changes at a specified location of the ***,when the neutron field changes are complex,the accurate identification of the individual changed regions becomes challenging,which seriously affects the accuracy and stability of the neutron field ***,this study proposed a dual-task hybrid network architecture(DTHNet)for off situ reconstruction of the core neutron field,which trained the outermost assembly reconstruction task and the core reconstruction task jointly such that the former could assist the latter in the reconstruction of the core neutron field under core complex ***,to exploit the characteristics of the ex-core detection signals,this study designed a global-local feature upsampling module that efficiently distributed the ex-core detection signals to each reconstruction unit to improve the accuracy and stability of *** experiments were performed on the simulation datasets of the CLEAR-I reactor to verify the accuracy and stability of the proposed *** results showed that when the location uncertainty of a single region did not exceed nine and the number of multiple changed regions did not exceed ***,the reconstructed ARD was within 2%,RD_(max)was maintained within 17.5%,and the number of RD≥10%was maintained within ***,when the noise interference of the ex-core detection signals was within±2%,although the average number of RD≥10%increased to 16,the average ARD was still within in 2%,and the average RD_(max)was within 22%.Collectively,these results show that,theoretically,the DTHNet can accurately and stably reconstruct most of the neutron field under certain complex core changes.

关键词： Real-time reactor monitoring Core neutron field reconstruction Dual-task hybrid network architecture Global-local feature upsampling module

Genome-wide association study reveals that enolase gene OsEE1 regulates coleoptile elongation in rice under anaerobic conditions

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Crop Journal 2025年第1期13卷 215-226页

作者： Li, Dandan Liu, Kai Su, Ling Li, Jinrui guo, Yuanyuan guo, Tao Liu, Hong Rao, Dehua College of Agriculture South China Agricultural University Guangdong Guangzhou 510642 China Jiangxi Academy of Eco-Environmental Sciences and Planning/Jiangxi Key Laboratory of Environmental Pollution Control Jiangxi Nanchang 330039 China

Submergence can induce anaerobic stress on germinating seedlings in direct seeded rice paddy fields, limiting the practice of direct seeding. Longer coleoptiles improves the anaerobic tolerance of rice seedlings under submerged conditions. In a search for genes that could be beneficial for developing submergence-tolerant varieties 148 non-repetitive SNP loci were detected in on a genome-wide association study (GWAS) of coleoptile length (CL), coleoptile surface area (CSA), coleoptile volume (CV), and coleoptile diameter (CD) of 591 rice accessions subjected to 4 d of anaerobic conditions. Integration of GWAS results and gene expression data identified OsEE1, an early embryogenesis-specific enolase 1 gene associated with coleoptile length (CL) in rice grown in anaerobic conditions. Disruption of OsEE1 caused reduced CL in plants seeded under anaerobic conditions, whereas CL of OE-OsEE1 overexpression lines was significantly increased compared with the wild type. Functional analysis revealed that OsEE1 affects coleoptile length by modulating the glycolysis and tricarboxylic acid cycle pathways. Transcriptome sequencing of ko-osee1-1 knock out mutants highlighted enrichment in energy and carbohydrate metabolism, glycolysis, amino acid metabolism, and hormone signal transduction. Metabolite analysis indicated decreased levels of key metabolites in the tricarboxylic acid cycle and glycolysis pathways in ko-osee1-1 mutants compared to the wild type under anaerobic conditions. Overall, these findings shed light on the role of OsEE1 in determination coleoptile length of rice seedlings under anaerobic conditions. © 2024 Crop Science Society of China and Institute of Crop Science, CAAS

关键词： Coleoptile length Early embryogenesis-specific enolase 1 GWAS OsEE1 Rice

Artificial intelligence advances drug delivery system and its clinical transition

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Science Bulletin 2025年第3期70卷 305-308页

作者： Hui Wang Xiao-Yan You guo-Ping Zhao Master Lab for Innovative Application of Nature Products National Center of Technology Innovation for Synthetic BiologyTianjin Institute of Industrial BiotechnologyChinese Academy of Sciences(CAS)Tianjin 300308China Henan Engineering Research Center of Food Microbiology College of Food and BioengineeringHenan University of Science and TechnologyLuoyang 471023China Haihe Laboratory of Synthetic Biology Tianjin 300308China CAS-Key Laboratory of Synthetic Biology CAS Center for Excellence in Molecular Plant SciencesShanghai Institute of Plant Physiology and EcologyChinese Academy of SciencesShanghai 200032China CAS Key Laboratory of Quantitative Engineering Biology Shenzhen Institute of Synthetic BiologyShenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhen 518055China

Since November 2022,ChatGPT,an artificial intelligence(AI)chatbot,has rapidly captured global attention for its detailed responses and articulated answers across a broad spectrum of knowledge domains[1],[2].All industries will reorient around it,prompting a reevaluation of how this technology could further promote scientifical research and its clinical applications.

关键词： system transition spectrum

Stress anisotropy regulated wrinkling pattern evolution on a core-shell soft cylinder

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Science China(Physics,Mechanics & Astronomy) 2025年第2期68卷 132-144页

作者： Yan Zhao Zhipan Jie Yilong Zhang guo-Yang Li Yanping Cao Chao Jiang State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body College of Mechanical and Vehicle EngineeringHunan UniversityChangsha 410082China Department of Mechanics and Engineering Science College of EngineeringPeking UniversityBeijing 100871China Institute of Biomechanics and Medical Engineering AMLDepartment of Engineering MechanicsTsinghua UniversityBeijing100084China

Diverse wrinkling patterns can occur on curved bilayer systems under differential growth or *** such systems,stress anisotropy is frequently encountered,and the coupling effect of curvature and stress anisotropy on the pattern evolution remains largely *** this study,we investigate the evolution of wrinkling patterns on a cylinder core-shell system with stress anisotropy leveraging both theoretical analysis and finite element *** buckling analysis has identified three distinct critical buckling modes regulated by the stress anisotropy,i.e.,axial sinusoidal mode,checkerboard mode,and circumferential sinusoidal *** finite element simulations,along with post-buckling analysis,reveal seven distinct evolutionary paths stemming from the three critical buckling *** present phase diagrams for both the critical buckling modes and their evolutionary paths,which are determined by dimensionless curvature and stress *** results not only expand the theoretical research on surface wrinkling of a core-shell soft cylinder but also introduce stress anisotropy as a significant parameter for regulating the wrinkling patterns and their evolutionary paths in curved bilayer *** revelation of a multitude of wrinkling patterns and their evolutionary pathways holds great potential for advancing applications that leverage tunable wrinkle surfaces.

关键词： wrinkling pattern evolutionary path stress anisotropy dimensionless curvature core-shell soft cylinder

New Insights on Gamma-Ray Burst Radiation Mechanisms from Multiwavelength Observations

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Research in Astronomy and Astrophysics 2025年第2期25卷 3-12页

作者： Yu-Hua Yao Fang-Sheng Min Shi Chen Yi-Qing guo College of Physics Chongqing University Key Laboratory of Particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences Wisconsin Ice Cube Particle Astrophysics Center University of Wisconsin–Madison University of Chinese Academy of Sciences School of Physics and Astronomy Yunnan University Tianfu Cosmic Ray Research Center

The study of high-energy gamma-ray emission from gamma-ray bursts(GRBs) involves complex synchrotron radiation and synchrotron self-Compton(SSC) scattering mechanisms with multiple parameters exhibiting a wide distribution. Recent advancements in GRB research, particularly the observation of very high energy(VHE,>100 Ge V) radiation, have ushered in a new era of multiwavelength exploration, offering fresh perspectives and limitations for understanding GRB radiation mechanisms. This study aimed to leverage VHE observations to refine constraints on synchrotron + SSC radiation from electrons accelerated by forward shocks. By analyzing two external environments—the uniform interstellar medium and stratified stellar wind medium, we conducted spectral and variability fitting for five specific bursts(GRB 180720B, GRB 190114C, GRB 190829A, GRB 201216C, and GRB 221009A) to identify the optimal parameters characterizing these events. A comparative analysis of model parameter distributions with and without VHE radiation observations reveals that the magnetic energy equipartition factor εBis more concentrated with VHE emissions. This suggests that VHE emissions may offer greater constraints on this microphysical parameter. Additionally, we found that the energy budget between VHE and ke V–Me V γ-ray emissions under the SSC radiation exhibits an almost linear relationship, which may serve as a tool to differentiate radiation mechanisms. We anticipate future statistical analyses of additional VHE bursts to validate our findings.

关键词： (transients:) gamma-ray bursts gamma-rays: ISM radiation mechanisms: non-thermal

The complex effects of miR-146a in the pathogenesis of Alzheimer's disease

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Neural Regeneration Research 2025年第5期20卷 1309-1323页

作者： Yunfan Long Jiajia Liu Yu Wang Haidong guo guohong Cui Department of Neurology Shanghai No.9 People’s HospitalShanghai Jiaotong University School of MedicineShanghaiChina Academy of Integrative Medicine Shanghai University of Traditional Chinese MedicineShanghaiChina School of Integrative Medicine Shanghai University of Traditional Chinese MedicineShanghaiChina Department of Neurology Shuguang Hospital Affiliated to Shanghai University of Traditional Chinese MedicineShanghaiChina

Alzheimer's disease is a neurodegenerative disorder characterized by cognitive dysfunction and behavioral *** plaques formed through the extracellular deposition of amyloid-βproteins,as well as neurofibrillary tangles formed by the intracellular deposition of hyperphosphorylated tau proteins,comprise two typical pathological features of Alzheimer's *** symptomatic treatment,there are no effective therapies for delaying Alzheimer's disease ***(miR)are small,non-coding RNAs that negatively regulate gene expression at the transcriptional and translational levels and play important roles in multiple physiological and pathological ***,miR-146a,a NF-κB-regulated gene,has been extensively implicated in the development of Alzheimer's disease through several *** has demonstrated substantial dysregulation of miR-146a both during the initial phases and throughout the progression of this *** R-146a is believed to reduce amyloid-βdeposition and tau protein hyperphosphorylation through the TLR/IRAK1/TRAF6 pathway;however,there is also evidence supporting that it can promote these processes through many other pathways,thus exacerbating the pathological manifestations of Alzheimer's *** has been widely reported that miR-146a mediates synaptic dysfunction,mitochondrial dysfunction,and neuronal death by targeting m RNAs encoding synapticrelated proteins,mitochondrial-related proteins,and membrane proteins,as well as other *** the impact on glial cells,miR-146a also exhibits differential *** one hand,it causes widespread and sustained inflammation through certain pathways,while on the other hand,it can reverse the polarization of astrocytes and microglia,alleviate neuroinflammation,and promote oligodendrocyte progenitor cell differentiation,thus maintaining the normal function of the myelin sheath and exerting a protective effect on *** this review,we provide a

关键词： Alzheimer's disease amyloid-β glial cells microRNAs miR-146a neuroinflammatory

Counterfactual Learning on Graphs:A Survey

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Machine Intelligence Research 2025年第1期22卷 17-59页

作者： Zhimeng guo Zongyu Wu Teng Xiao Charu Aggarwal Hui Liu Suhang Wang College of Information Sciences and Technology Pennsylvania State UniversityUniversity Park 16802USA International Business Machines Corporation T.J.Watson Research Center New York 10598USA College of Engineering Michigan State UniversityEast Lansing 48824USA

Graph-structured data are pervasive in the real-world such as social networks,molecular graphs and transaction *** neural networks(GNNs)have achieved great success in representation learning on graphs,facilitating various downstream ***,GNNs have several drawbacks such as lacking interpretability,can easily inherit the bias of data and cannot model casual ***,counterfactual learning on graphs has shown promising results in alleviating these *** approaches have been proposed for counterfactual fairness,explainability,link prediction and other applications on *** facilitate the develop-ment of this promising direction,in this survey,we categorize and comprehensively review papers on graph counterfactual *** divide existing methods into four categories based on problems *** each category,we provide background and motivating ex-amples,a general framework summarizing existing works and a detailed review of these *** point out promising future research directions at the intersection of graph-structured data,counterfactual learning,and real-world *** offer a comprehensive view of resources for future studies,we compile a collection of open-source implementations,public datasets,and commonly-used evalu-ation *** survey aims to serve as a“one-stop-shop”for building a unified understanding of graph counterfactual learning cat-egories and current resources.

关键词： Counterfactual learning graph-structured data graph neural networks fairness explainability