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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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Olfactory dysfunction and its related molecular mechanisms in Parkinson’s disease

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Neural Regeneration Research 2024年第3期19卷 583-590页

作者： Yingying Gu Jiaying Zhang Xinru Zhao Wenyuan Nie xiaole Xu Mingxuan liu Xiaoling Zhang College of Pharmacy Nantong UniversityNantongJiangsu ProvinceChina

Changes in olfactory function are considered to be early biomarkers of Parkinson’s disease.Olfactory dysfunction is one of the earliest non-motor features of Parkinson’s disease,appearing in about 90%of patients with early-stage Parkinson’s disease,and can often predate the diagnosis by years.Therefore,olfactory dysfunction should be considered a reliable marker of the disease.However,the mechanisms responsible for olfactory dysfunction are currently unknown.In this article,we clearly explain the pathology and medical definition of olfactory function as a biomarker for early-stage Parkinson’s disease.On the basis of the findings of clinical olfactory function tests and animal model experiments as well as neurotransmitter expression levels,we further characterize the relationship between olfactory dysfunction and neurodegenerative diseases as well as the molecular mechanisms underlying olfactory dysfunction in the pathology of early-stage Parkinson’s disease.The findings highlighted in this review suggest that olfactory dysfunction is an important biomarker for preclinical-stage Parkinson’s disease.Therefore,therapeutic drugs targeting non-motor symptoms such as olfactory dysfunction in the early stage of Parkinson’s disease may prevent or delay dopaminergic neurodegeneration and reduce motor symptoms,highlighting the potential of identifying effective targets for treating Parkinson’s disease by inhibiting the deterioration of olfactory dysfunction.

关键词： biomarker early-stage olfactory disorders olfactory dysfunction Parkinson’s disease

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An investigation on topologies of hybrid manifold,impinging-jet nozzle and micro-pin-fin heat sinks

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Science China(Technological Sciences) 2024年第4期67卷 1061-1076页

作者： SHI QianLei YAO xiaole liu Qian QIN Le JU Xing XU Chao Key Laboratory of Power Station Energy Transfer Conversion and System of MOE North China Electric Power UniversityBeijing 102206China

The hybrid manifold micro-pin-fin(MMPF)heat sink combined nozzle jets is an option for large-scale integrated circuits(LSI).The demond for uniform and ultra-high heat flux removal by MMPF heat sink has not been adequately investigated.This work aims to solve the problem of fluid organization.The proposed basic tiling topologies,including square,regular hexagon,30°rhombus,and 60°rhombus topologies,provide different organized fluid flows and heat transfer patterns.The present study focuses on comparing these topologies according to independent porous medium parameters,such as nozzle pore size D_(Z),flow pore size D_(X,Y),and porosityε.The results show that the square topology achieves the smallest total thermal resistance R_(tot)value of0.0975×10^(-4)K m^2/W,while the hexagon topology achieved the highest value of COP/?T,which was 2033.9 K^(-1).According to the sensitivity analysis results,the optimal total thermal resistance can be obtained by balancing the influences of nozzle pore size,flow pore size,and porosity.The optimal pressure drop can be obtained by maximizing the porosity.

关键词： heat sink ultra-high heat flux manifold micro-pin-fin impinging-jet topology

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Characteristics and source apportionment of ambient volatile organic compounds and ozone generation sensitivity in urban Jiaozuo,China

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Journal of Environmental Sciences 2024年第4期138卷 607-625页

作者： Pengzhao Li Chun Chen Dan liu Jie Lian Wei Li Chuanyi Fan Liangyu Yan Yue Gao Miao Wang Hang liu xiaole Pan Jing Mao State Centre for International Cooperation on Designer Low-Carbon and Environmental Materials School of Materials Science and EngineeringZhengzhou UniversityZhengzhou 450001China Henan Key Laboratory of Environmental Monitoring Technology Henan Ecological Environment Monitoring and Safety CenterZhengzhou 450046China Jiaozuo Ecological Environment Monitoring Center of Henan Province Jiaozuo 454003China State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China

In recent years,many cities have taken measures to reduce volatile organic compounds(VOCs),an important precursor of ozone(O_(3)),to alleviate O_(3) pollution in China.116 VOC species were measured by online and offline methods in the urban area of Jiaozuo from May to October in 2021 to analyze the compositional characteristics.VOC sources were analyzed by a positive matrix factorization(PMF)model,and the sensitivity of ozone generation was determined by ozone isopleth plotting research(OZIPR)simulation.The results showed that the average volume concentration of total VOCs was 30.54 ppbv and showed a bimodal feature due to the rush-hour traffic in the morning and at nightfall.The most dominant VOC groups were oxygenated VOCs(OVOCs,29.3%)and alkanes(26.7%),and the most abundant VOC species were acetone and acetylene.However,based on the maximum incremental reactivity(MIR)method,the major VOC groups in terms of ozone formation potential(OFP)contribution were OVOCs(68.09μg/m^(3),31.5%),aromatics(62.90μg/m^(3),29.1%)and alkene/alkynes(54.90μg/m^(3),25.4%).This indicates that the control of OVOCs,aromatics and alkene/alkynes should take priority.Five sources of VOCs were quantified by PMF,including fixed sources of fossil fuel combustion(27.8%),industrial processes(25.9%),vehicle exhaust(19.7%),natural and secondary formation(13.9%)and solvent usage(12.7%).The empirical kinetic modeling approach(EKMA)curve obtained by OZIPR on O_(3) exceedance days indicated that the O_(3) sensitivity varied in different months.The results provide theoretical support for O_(3) pollution prevention and control in Jiaozuo.

关键词： Volatile organic compounds(VOCs) Online and offline measurement Ozone formation potential(OFP) Positive matrix factorization(PMF) Ozone isopleth plotting research(OZIPR) Jiaozuo

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Development and evaluation of an online monitoring single-particle optical particle counter with polarization detection

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Journal of Environmental Sciences 2024年第4期138卷 585-596页

作者： Weijie Yao xiaole Pan Yu Tian Hang liu Yuting Zhang Shandong Lei Junbo Zhang Yinzhou Zhang LinWu Yele Sun Zifa Wang 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 Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China

We developed a single-particle optical particle counter with polarization detection(SOPC)for the real-time measurement of the optical size and depolarization ratio(defined as the ratio of the vertical component to the parallel component of backward scattering)of atmospheric particles,the polarization ratio(DR)value can reflect the irregularity of the particles.The SOPC can detect aerosol particles with size larger than 500 nm and the maximum particle count rate reaches~1.8×10^(5)particles per liter.The SOPC uses a modulated polarization laser to measure the optical size of particles according to forward scattering signal and the DR value of the particles by backward S and P signal components.The sampling rate of the SOPC was 106#/(sec·channel),and all the raw data were processed online.The calibration curve was obtained by polystyrene latex spheres with sizes of 0.5-10μm,and the average relative deviation of measurement was 3.96% for sub 3μm particles.T-matrix method calculations showed that the DR value of backscatter light at 120°could describe the variations in the aspect ratio of particles in the above size range.We performed insitu observations for the evaluation of the SOPC,the mass concentration constructed by the SOPC showed good agreement with the PM_(2.5)measurements in a nearby state-controlled monitoring site.This instrument could provide useful data for source appointment and regulations against air pollution.

关键词： Instrument development Single particle detection Measurement uncertainty Optical simulation Mass concentration

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Adaptive learning path recommendation model for examination-oriented education

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The Journal of China Universities of Posts and Telecommunications 2022年第4期29卷 77-88页

作者： Wang Jian Qiao Kuoyuan Yuan Yanlei liu xiaole Yang Jian School of Computer and Artificial Intelligence Zhengzhou UniversityZhengzhou 450001China Research and Development Department Tongfang Knowledge Network Technology Company LimitedBeijing 100192China The Teaching Affaires Office Zhengzhou Hi-Tech Zone Langyuehui Foreign Language Middle SchoolZhengzhou 450001China Yunnan Key Laboratory of Smart City in Cyberspace Security Yuxi Normal UniversityYuxi 653100China

Adaptive learning paths provide individual learning objectives that best match a learner’s characteristics.This is especially helpful when learners need to balance limited available learning time and multiple learning objectives.The automatic generation of personalized learning paths to improve learning efficiency has therefore attracted significant interest.However,most current research only focuses on providing learners with adaptive objects and sequences according to their own interests or learning goals given a normal amount of time or ordinary conditions.There is little research that can help learners to obtain the most important knowledge for a test in the shortest time possible,which is a typical scenario in exanimation-oriented education systems.This study aims to solve this problem by introducing a new approach that builds on existing methods.First,the eight properties in Gardner’s multiple intelligence theory are introduced into the present knowledge and learner models to define the relationship between learning objects(LOs)and learners,thereby improving recommendation accuracy rates.Then,a novel adaptive learning path recommendation model is presented where viable knowledge topologies,knowledge bases and the previously-established properties relating to a learner’s ability are combined by Dempster-Shafer(D-S)evidence theory.A series of practical experiments were performed to assess the approach’s adaptability,the appropriateness of the selected evidence and the effectiveness of the recommendations.In the results,it was found that the proposed learning path recommendation model helped learners learn the most important elements and obtain superior test grades when confronted with limited time for learning.

关键词： adaptive learning learning path recommendation Dempster-Shaferevidence theory knowledge model learner model

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A novel live attenuated vaccine candidate protects chickens against subtype B avian metapneumovirus

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Journal of Integrative Agriculture 2024年第5期23卷 1658-1670页

作者： Lingzhai Meng Mengmeng Yu Suyan Wang Yuntong Chen Yuanling Bao Peng liu Xiaoyan Feng Tana He Ru Guo Tao Zhang Mingxue Hu Changjun liu xiaole Qi Kai Li Li Gao Yanping Zhang Hongyu Cui Yulong Gao Avian Immunosuppressive Diseases Division State Key Laboratory for Animal Disease Control and PreventionHarbin Veterinary Research InstituteChineseAcademy of Agricultural SciencesHarbin150069China Avian ImmunosuppressiveDiseases DivisionStateKey LaboratoryforAnimal Disease Cont National Poultry Laboratory Animal Resource Center Harbin 150069China

Avian metapneumovirus(aMPV) is a highly contagious pathogen that causes acute upper respiratory tract diseases in chickens and turkeys, resulting in serious economic losses. Subtype B aMPV has recently become the dominant epidemic strain in China. We developed an attenuated aMPV subtype B strain by serial passaging in Vero cells and evaluated its safety and efficacy as a vaccine candidate. The safety test showed that after the 30th passage, the LN16-A strain was fully attenuated, as clinical signs of infection and histological lesions were absent after inoculation.The LN16-A strain did not revert to a virulent strain after five serial passages in chickens. The genomic sequence of LN16-A differed from that of the parent wild-type LN16(wtLN16) strain and had nine amino acid mutations. In chickens, a single immunization with LN16-A induced robust humoral and cellular immune responses, including the abundant production of neutralizing antibodies, CD4^(+) T lymphocytes, and the Th1(IFN-γ) and Th2(IL-4 and IL-6)cytokines. We also confirmed that LN16-A provided 100% protection against subtype B aMPV and significantly reduced viral shedding and turbinate inflammation. Our findings suggest that the LN16-A strain is a promising live attenuated vaccine candidate that can prevent infection with subtype B aMPV.

关键词： avian metapneumovirus attenuated protection vaccine candidate chickens

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Inulin alleviates HFD-induced NAFLD by hepatic macrophage polarization and lipid metabolism via gut-liver axis

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Food Science and Human Wellness 2024年

作者： Wei Song Jinhong Hu Lina Zhu Bing Chen Lingling Li xiaole Cui Ting Zhang Yaxing Miao Kaixin Su Changchun liu Yane Luo Tianli Yue College of Food Science and Technology Laboratory of Nutritional and Healthy Food-Individuation Manufacturing Engineering Research Center of Food Safety Risk Assessment and Control Northwest University

Long-term intake of high-fat diet (HFD) leads to systemic hypo-inflammation， which is involved in the pathogenesis of many liver diseases. The aim of this study was to evaluate the interventional effect of inulin addition on HFD-induced non-alcoholic fatty liver disease (NAFLD). Here， we assessed liver inflammation and lipid metabolism by ELISA kits and real-time quantitative polymerase chain reaction (qPCR)， and explored its relationship with intestinal flora and metabolites by 16S rDNA gene sequencing and untargeted metabolomics. In addition， we determined the effect of the inositol-requiring enzyme-1α (IRE1α-XBP1) pathway on liver macrophage polarization by flow cytometry. In conclusion， our study has demonstrated that inulin ameliorates high levels of bile acids and colonic immune disorders induced by HFD， and improves hepatic macrophage polarization and hepatic lipid metabolism via the intestine-hepatic axis， thus providing a mechanistic basis for therapeutic approaches to modulate bile acids to improve colonic inflammation and nonalcoholic fatty liver disease.

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牙周炎患者牙周支持治疗对血细胞指标影响的回顾性研究

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国际口腔医学杂志 2024年第4期51卷 401-405页

作者：陈梦洁刘小乐朱丽雷湖南中医药大学研究生院长沙410208 长沙市口腔医院牙周病科长沙410000

目的探讨牙周炎患者牙周支持治疗对血细胞指标的影响。方法按照纳入及排除标准,选取2014年1月—2022年3月于长沙市口腔医院就诊且被确诊为牙周炎的患者为研究对象。根据是否定期进行牙周支持治疗,分为定期支持治疗组(74例)和不定期支持... 详细信息

目的探讨牙周炎患者牙周支持治疗对血细胞指标的影响。方法按照纳入及排除标准,选取2014年1月—2022年3月于长沙市口腔医院就诊且被确诊为牙周炎的患者为研究对象。根据是否定期进行牙周支持治疗,分为定期支持治疗组(74例)和不定期支持治疗组(76例),对比两组血细胞指标水平变化。结果定期支持治疗组中性粒细胞计数(N)、白细胞计数(WBC)、血小板计数(PLT)、全身免疫炎症指数(SII)均低于治疗前(P0.05)。治疗后不定期支持治疗组SII较治疗前下降,MPV、MCV则增大(P<0.05)。两组患者治疗后WBC、N、PLT、SII、MCV、MCHC和MPV之间差异有统计学意义(P<0.05)。在5年随访期间,定期支持治疗组WBC、N、PLT、SII呈下降趋势;MCHC、MPV、MCV呈增长趋势。结论积极的牙周支持治疗能改善牙周炎患者的血液学参数,缓解体内免疫与炎症失衡状态,有利于治疗效果的维护与提高。

关键词：牙周炎牙周支持治疗血细胞

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体位限制下康复机器人训练对脑卒中后肩关节半脱位患者上肢功能的效果

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中国康复理论与实践 2024年第3期30卷 303-309页

作者：刘换韩雪宋佳苧娄晓乐徐磊蚌埠医科大学第一附属医院康复医学科安徽蚌埠市233000

目的探讨体位限制下上肢康复机器人训练对脑卒中后肩关节半脱位患者上肢功能的临床疗效。方法 2023年3月至12月,蚌埠医科大学第一附属医院脑卒中后肩关节半脱位患者60例随机分为常规组(n=20)、机器人组(n=20)和体位限制组(n=20)。3组... 详细信息

目的探讨体位限制下上肢康复机器人训练对脑卒中后肩关节半脱位患者上肢功能的临床疗效。方法 2023年3月至12月,蚌埠医科大学第一附属医院脑卒中后肩关节半脱位患者60例随机分为常规组(n=20)、机器人组(n=20)和体位限制组(n=20)。3组均进行常规康复治疗,机器人组行上肢康复机器人训练,体位限制组在体位限制下行上肢康复机器人训练,共4周。治疗前后采用Fugl-Meyer评定量表上肢部分(FMA-UE)、改良Barthel指数(MBI)进行评定,表面肌电图(sEMG)检测三角肌后束和冈上肌收缩时的平均肌电值(AEMG)和均方根值(RMS),肌骨超声测量患侧肩峰-大结节(AGT)间距。结果治疗后,3组FMA-UE评分、MBI评分、AEMG、RMS和AGT间距均较治疗前显著改善(|t|> 10.850, P 42.031, P <0.001)。结论体位限制下上肢康复机器人训练能进一步改善脑卒中后肩关节半脱位患者的上肢功能及脱位状态、提高日常生活能力及肩周肌肉功能。

关键词：脑卒中肩关节半脱位上肢机器人康复

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