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Analysis of amino acid enantiomers in ambient aerosols:Effects and removal of coexistent aerosol matrix

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Journal of Environmental Sciences 2024年第3期137卷 732-740页

作者： ying li Xiaoying li libin wu Luhan Shi ShanWang Pingqing Fu yingyi Zhang Senchao Lai The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters Ministry of EducationSchool of Environment and EnergySouth China University of TechnologyGuangzhou 510006China Institute of Surface-Earth System Science School of Earth System ScienceTianjin UniversityTianjin 300072China now at Hong Kong University of Science and Technology Hong Kong 00852China

Amino acids(AAs)including D-and L-enantiomers are a group of organic nitrogen species in ambient aerosol.Due to the low abundances of AAs(level of ng/m^(3))and the matrix effects by coexistent components,it is challenging to quantify AA enantiomers in ambient aerosols especially under pollution conditions.In this study,we present an optimized method for analyzing AA enantiomers in atmospheric aerosol samples including a pretreatment process and the detection by high performance liquid chromatography coupled to a fuorescence detector(HPLC-FLD).Matrix effects caused by coexistent chemicals on AA enantiomers analysis in ambient aerosol samples were investigated especially for those collected in pollution episodes.The results revealed that the determination of AA enantiomers is significantly affected by the coexistent organic carbon(as a proxy of organic matter)and water-soluble ion of NH_(4)^(+).To remove the matrix effects,we applied a pretreatment using the solid phase extraction column coupled with alkaline adjustment to sample extract.After pretreatment,18 AAs including 6 pairs of D-and L-enantiomers(i.e.,leucine,isoleucine,valine,alanine,serine,and aspartic acid)can be successfully separated and quantified in aerosol samples by HPLC-FLD.The recoveries are in the range of 67%-106%.This method was successfully applied to the urban aerosol samples from pollution and non-pollution periods for AA enantiomers determination.We suggest that the concentrations of D-AAs and the ratio of D-AA/L-AA are indicative of the contribution of bacterial sources and the infuence of biomass burning.

关键词： Amino acid enantiomers Atmospheric aerosol Organic carbon Ammonia Chiral ratio

Flotation separation of scheelite from calcite using luteolin as a novel depressant

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International Journal of Minerals,Metallurgy and Materials 2024年第3期31卷 462-472页

作者： Xiaokang li ying Zhang Haiyang He Yu wu Danyu wu Zhenhao Guan Faculty of Land and Resources Engineering Kunming University of Science and TechnologyKunming 650093China State Key Laboratory of Clean Utilization of Complex Non-Ferrous Metal Resources Kunming University of Science and TechnologyKunming 650093China

This paper proposes luteolin(LUT)as a novel depressant for the flotation-based separation of scheelite and calcite in a sodium oleate(NaOL)system.The suitability of LUT as a calcite depressant is confirmed through micro-flotation testing.At pH=9,with LUT concentration of 50 mg·L^(-1) and NaOL concentration of 50 mg·L^(-1),scheelite recovery reaches 80.3%.Calcite,on the other hand,exhibits a recovery rate of 17.6%,indicating a significant difference in floatability between the two minerals.Subsequently,the surface modifica-tions of scheelite and calcite following LUT treatment are characterized using adsorption capacity testing,Zeta potential analysis,Fourier transform infrared spectroscopy(FT-IR),X-ray photoelectron spectroscopy(XPS),and atomic force microscopy(AFM).The study in-vestigates the selective depressant mechanism of LUT on calcite.Adsorption capacity testing and Zeta potential analysis demonstrate sub-stantial absorption of LUT on the surface of calcite,impeding the further adsorption of sodium oleate,while its impact on scheelite is min-imal.FT-IR and XPS analyses reveal the selective adsorption of LUT onto the surface of calcite,forming strong chemisorption bonds between the hydroxyl group and calcium ions present.AFM directly illustrates the distinct adsorption densities of LUT on the two miner-al types.Consequently,LUT can effectively serve as a depressant for calcite,enabling the successful separation of scheelite and calcite.

关键词： scheelite calcite luteolin flotation depressant separation

Effect of short neuropeptide F signaling on larval feeding in Mythimna separata

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Insect Science 2024年第2期31卷 417-434页

作者： Mei-Mei li Qi Yang li-Hui Chen Yan-ying li Jun-Xiang wu Xiang-li Xu State Key Laboratory of Crop Stress Biology in Arid Areas College of Plant ProtectionNorthwest A&F UniversityYanglingShaanxi ProvinceChinaand School of Agricultural Sciences Jiangxi Agricultural UniversityNanchangChina

Mythimna separata is a notorious phytophagous pest which poses serious threats to cereal crops owing to the gluttony of the larvae.Because short neuropeptide F(sNPF)and its receptor sNPFR are involved in a diversity of physiological functions,especially in functions related to feeding in insects,it is a molecular target for pest control.Herein,an sNPF and 2 sNPFRs were identified and cloned from M.separata.Bioinformatics analysis revealed that the sNPF and its receptors had a highly conserved RLRFamide C-terminus and 7 transmembrane domains,respectively.The sNPF and its receptor genes were distributed across larval periods and tissues,but 2 receptors had distinct expression patterns.The starvation-induced assay elucidated that sNPF and sNPFR expression levels were downregulated under food deprivation and recovered with subsequent re-feeding.RNA interference knockdown of sNPF,sNPFR1,and sNPFR2 by injection of double-stranded RNA into larvae not only suppressed food consumption and increased body size and weight,but also led to decrease of glycogen and total lipid contents,and increase of trehalose compared with double-stranded green fluorescent protein injection.Furthermore,molecular docking was performed on the interaction mode between sNPFR protein and its ligand sNPF based on the 3-dimensional models constructed by AlphaFold;the results indicated that both receptors were presumably activated by the mature peptide sNPF-2.These results revealed that sNPF signaling played a considerably vital role in the feeding regulation of M.separata and represents a potential control target for this pest.

关键词： feeding regulation Mythimna separata pest control target RNA interference short neuropeptide F sNPF receptors

Afterglow Nanoprobes for In-vitro Background-free Biomarker Analysis

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Chemical Research in Chinese Universities 2024年第2期40卷 213-224页

作者： ZHENG Ting WANG ying li Xianming li Chenghui wu Peng Analytical&Testing Centre State Key Laboratory of Hydraulics and Mountain River EngineeringSichuan UniversityChengdu610064P.R.China School of Chemistry and Chemical Engineering Henan Normal UniversityXinxiang453007P.R.China Department of Rheumatology and Immunology West China HospitalSichuan UniversityChengdu610064P.R.China

Accurate detection of biomarkers is essential for disease diagnosis.Although the highly sensitive fluorescence probes are feasible for the above goal,it is typically interfered by the auto-fluorescence and light scattering of the biological samples.Photochemical afterglow system(consisting of photosensitizer,afterglow substrate and emitter)based on cascade photochemical reactions exhibits long-lived luminescence(seconds to hours),thus avoiding background interference.With the assistance of polymers,such as polystyrene microspheres,the photochemical afterglow systems have been transformed into homogeneous and water-soluble nanoparticles,and used for in-vitro biomarker analysis.Here,we summarized the principle,preparation and applications of these afterglow nanoparticles,and evaluated their performance in clinical sample testing by comparing with other nanoparticle-based methods.Finally,several problems and possible solutions of afterglow nanoparticle-based methods in biomarker determination were also mentioned.

关键词： Photochemical afterglow In-vitro analysis Background-free detection Biomarker

Micro-aluminum powder with bi-or tri-component alloy coating as a promising catalyst:Boosting pyrolysis and combustion of ammonium perchlorate

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Defence Technology（防务技术） 2024年第3期33卷 100-113页

作者： Chao Wang ying liu Mingze wu Jia li ying Feng Xianjin Ning Hong li Ningfei Wang Baolu Shi School of Aerospace Engineering Beijing Institute of TechnologyBeijing 100081China School of Materials Science and Engineering Beijing Institute of TechnologyBeijing 100081China State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China

A novel design of micro-aluminum(μAl)powder coated with bi-/tri-component alloy layer,such as:Ni-P and Ni-P-Cu(namely,Al@Ni-P,Al@Ni-P-Cu,respectively),as combustion catalysts,were introduced to release its huge energy inside Al-core and promote rapid pyrolysis of ammonium perchlorate(AP)at a lower temperature in aluminized propellants.The microstructure of Al@Ni-P-Cu demonstrates that a three-layer Ni-P-Cu shell,with the thickness of~100 nm,is uniformly supported byμAl carrier(fuel unit),which has an amorphous surface with a thickness of~2.3 nm(catalytic unit).The peak temperature of AP with the addition of Al@Ni-P-Cu(3.5%)could significantly drop to 316.2℃ at high-temperature thermal decomposition,reduced by 124.3℃,in comparison to that of pure AP with 440.5℃.It illustrated that the introduction of Al@Ni-P-Cu could weaken or even eliminate the obstacle of AP pyrolysis due to its reduction of activation energy with 118.28 kJ/mol.The laser ignition results showed that the ignition delay time of Al@Ni-P-Cu/AP mixture with 78 ms in air is shorter than that of Al@Ni-P/AP(118 ms),decreased by 33.90%.Those astonishing breakthroughs were attributed to the synergistic effects of adequate active sites on amorphous surface and oxidation exothermic reactions(7597.7 J/g)of Al@Ni-P-Cu,resulting in accelerated mass and/or heat transfer rate to catalyze AP pyrolysis and combustion.Moreover,it is believed to provide an alternative Al-based combustion catalyst for propellant designer,to promote the development the propellants toward a higher energy.

关键词： Micro-aluminum powder(μAl) Nano-sized alloy coating Combustion catalyst Ammonium perchlorate Pyrolysis behavior Ignition and combustion

Gene therapy for monogenic disorders: challenges, strategies, and perspectives

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Journal of Genetics and Genomics 2024年第2期51卷 133-143页

作者： Yi Zhang Zhi-ying wu Department of Medical Genetics and Center for Rare Diseases Second Affiliated HospitalZhejiang University School of MedicineHangzhouZhejiang 310009China Department of Neurology Second Affiliated HospitalZhejiang University School of MedicineHangzhouZhejiang 310009China Key Laboratory of Medical Neurobiology of Zhejiang Province HangzhouZhejiang 310009China

Monogenic disorders refer to a group of human diseases caused by mutations in single genes. While disease-modifying therapies have offered some relief from symptoms and delayed progression for some monogenic diseases, most of these diseases still lack effective treatments. In recent decades, gene therapy has emerged as a promising therapeutic strategy for genetic disorders. Researchers have developed various gene manipulation tools and gene delivery systems to treat monogenic diseases. Despite this progress, concerns about inefficient delivery, persistent expression, immunogenicity, toxicity, capacity limitation, genomic integration, and limited tissue specificity still need to be addressed. This review gives an overview of commonly used gene therapy and delivery tools, along with the challenges they face and potential strategies to counter them.

关键词： Gene therapy Monogenic diseases Geneediting Genedelivery Challenges

Risk factors for brain injury in patients with exertional heatstroke:A 5-year experience

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Chinese Journal of Traumatology 2024年第2期27卷 91-96页

作者： li Zhong Ming wu Zhe-ying liu Yan liu Zhi-Feng liu Department of Traditional Chinese Medicine The First Affiliated HospitalGuizhou University of Chinese MedicineGuiyang550001China Department of Infection and Critical Care Medicine The Second People's Hospital of Shenzhen&First Affiliated Hospital of Shenzhen UniversityHealth Science CenterShenzhenGuangdong province518035China Department of Medical Critical Care Medicine General Hospital of Southem Theatre Command of PLA.Guangzhou510010China Guangdong Branch Center National Clinical Research Center for Geriatric Diseases(Chinese PLA General Hospital)Guangzhou510010China

Purpose:Minimal data exist on brain injury in patients with exertional heatstroke(EHS)in developing country.In this study,we explored the risk factors for brain injury induced by EHS 90-day after onset.Methods:A retrospective cohort study of patients with EHS was conducted in the intensive care unit of the General Hospital of Southern Theater Command of PLA in China from April 2014 to June 2019.Patients were divided into non-brain injury(fully recovered)and brain injury groups(comprising deceased patients or those with neurological sequelae).The brain injury group was further subdivided into a death group and a sequela group for detailed analysis.General information,neurological performance and information on important organ injuries in the acute stage were recorded and analysed.Multivariable logistic regression was used to identify risk factors for brain injury after EHS and mortality risk factors for brain injury,and Kaplan-Meier survival curve was used to evaluate the effect of the neurological dysfunction on survival.Results:Out of the 147 EHS patients,117 were enrolled,of which 96(82.1%)recovered,13(11.1%)died,and 8(6.8%)experienced neurological sequelae.Statistically significant differences were found between non-brain injury and brain injury groups in age,hypotension,duration of consciousness disorders,time to drop core body temperature below 38.5℃,lymphocyte counts,platelet counts,procalcitonin,alanine aminotransferase,aspartate aminotransferase,creatinine,cystatin C,coagulation parameters,international normalized ratio,acute physiology and chronic health evaluation II scores,sequential organ failure assessment(SOFA)scores,and Glasgow coma scale scores(all p<0.05).Multivariate logistic regression showed that age(OR=1.090,95%CI:1.02-1.17,p=0.008),time to drop core temperature(OR=8.223,95%CI:2.30-29.40,p=0.001),and SOFA scores(OR=1.676,95%CI:1.29-2.18,p<0.001)are independent risk factors for brain injury induced by EHS.The Kaplan-Meier curves suggest significantly prolonged survival(p<0.001)in patients with

关键词： Exertional heatstroke Brain injury Sequela Risk factors Disorders of consciousness

DLP:towards active defense against backdoor attacks with decoupled learning process

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Cybersecurity 2024年第1期7卷 122-134页

作者： Zonghao ying Bin wu State Key Laboratory of Information Security Institute of Information EngineeringChinese Academy of SciencesBeijingChina School of Cyber Security University of Chinese Academy of SciencesBeijingChina

Deep learning models are well known to be susceptible to backdoor attack,where the attacker only needs to provide a tampered dataset on which the triggers are injected.Models trained on the dataset will passively implant the backdoor,and triggers on the input can mislead the models during testing.Our study shows that the model shows different learning behaviors in clean and poisoned subsets during training.Based on this observation,we propose a general training pipeline to defend against backdoor attacks actively.Benign models can be trained from the unreli-able dataset by decoupling the learning process into three stages,i.e.,supervised learning,active unlearning,and active semi-supervised fine-tuning.The effectiveness of our approach has been shown in numerous experiments across various backdoor attacks and datasets.

关键词： Deep learning Backdoor attack Active defense

Carbon-based interface engineering and architecture design for high-performance lithium metal anodes

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Carbon Energy 2024年第1期6卷 207-235页

作者： Na Zhu Yuxiang Yang Yu li ying Bai Junfeng Rong Chuan wu SINOPEC Research Institute of Petroleum Processing Co. Ltd.BeijingChina Beijing Key Laboratory of Environmental Science and Engineering School of Materials Science and EngineeringBeijing Institute of TechnologyBeijingChina Yangtze Delta Region Academy of Beijing Institute of Technology JiaxingChina

Metallic lithium(li)is considered the“Holy Grail”anode material for the nextgeneration of li batteries with high energy density owing to the extraordinary theoretical specific capacity and the lowest negative electrochemical potential.However,owing to inhomogeneous li-ion flux,li anodes undergo uncontrollable li deposition,leading to limited power output and practical applications.Carbon materials and their composites with controllable structures and properties have received extensive attention to guide the homogeneous growth of li to achieve high-performance li anodes.In this review,the correlation between the behavior of li anode and the properties of carbon materials is proposed.Subsequently,we review emerging strategies for rationally designing high-performance li anodes with carbon materials,including interface engineering(stabilizing solid electrolyte interphase layer and other functionalized interfacial layer)and architecture design of host carbon(constructing three-dimension structure,preparing hollow structure,introducing lithiophilic sites,optimizing geometric effects,and compositing with li).Based on the insights,some prospects on critical challenges and possible future research directions in this field are concluded.It is anticipated that further innovative works on the fundamental chemistry and theoretical research of li anodes are needed.

关键词： carbon materials dendrites hosts interfacial layers li metal anodes