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

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

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Effects of oxygen vacancy on bond ionicity,lattice energy,and microwave dielectric properties of CeO_(2) ceramics with Yb^(3+) substitution

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Journal of Advanced Ceramics 2024年第2期13卷 247-254页

作者： Mingan shi Shuyang Ma Wangsuo Xia ying Wang Jinzi Yu Haitao wu School of Materials Science and Physics China University of Mining and TechnologyXuzhou 221008China School of Environment and Material Engineering Yantai UniversityYantai 264005China

Novel Yb_(x)Ce_(1-x)O_(2-0.5x)(x=0-0.8)ceramics,designed by replacing Ce^(4+)with Yb^(3+)ions were prepared by conventional oxide reaction,and the structural stability of the cubic fluorite structure was assessed using lattice energy and ionic properties of Ce/Yb-O bonds.The oxygen vacancy caused by unequal substitution,which played a decisive role in bond ionicity and lattice energy,was analyzed experimentally by XPS and also theoretically by first principles.The Yb_(x)Ce_(1-x)O_(2-0.5x) ceramics maintain a stable cubic fluorite structure when x≤0.47,corresponding to the minimum lattice energy of 4142 kJ/mol with the lowest ionicity as ƒ_(i)=87.57%.For microwave dielectric properties,when the Yb_(x)Ce_(1-x)O_(2-0.5x)(x=0-0.4)ceramics are pure phase,the porosity-corrected permittivity is dependent on the bond ionicity.The Q×ƒ values are related to the lattice energy and grain distribution.The temperature coefficient of resonance frequency has been analyzed using bond valence.When the Yb_(x)Ce_(1-x)O_(2-0.5x)(x=0.5-0.8)ceramics are multiple phases,the microwave dielectric properties are associated with the phase composition and grain growth.

关键词： structure stability bond ionicity oxygen vacancy electronic localization function(ELF)

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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

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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

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Dynamical switchable quantum nonreciprocity induced by off-resonant chiral two-photon driving

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Science China(Physics,Mechanics & Astronomy) 2024年第6期67卷 31-37页

作者： Da-Wei Liu Zi-Hao Li shi-Lei Chao ying wu Liu-Gang Si School of Physics and Institute for Quantum Science and Engineering Huazhong University of Science and TechnologyWuhan 430074China

Optical nonreciprocity,which refers to the direction-dependent emission,scattering and absorption of photons,plays a very important role in quantum engineering and quantum information processing.Here,we propose an all-optical approach to achieve the optical dynamical switchable quantum nonreciprocity by an off-resonant chiral two-photon driving in a single microring cavity,which differs from the conventional nonreciprocal schemes.It is shown that the optical field with time-dependent statistical properties can be generated and the nonreciprocity flips periodically,with switchable photon blockade and photon-induced tunneling effects.We find that the dynamical system is robust and immune to the parameter variations,which loosens the parameter range of system.Meanwhile,the time window for one-way quantum information is sufficiently wide and tunable.Our work opens a new idea for the current quantum nonreciprocal research,which can facilitate a memory functionality and be used for future inmemory superconducting quantum compute.The other nonreciprocal quantum devices,i.e.,dynamical switchable nonreciprocal squeezing and entanglement,may be inspired by our method,which is expected to have important applications in future quantum technology.

关键词： dynamical switchable nonreciprocity single-photon source chiral two-photon driving

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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

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Successful management of severe hypoglycemia induced by total parenteral nutrition in patients with hepatocellular injury: Three cases reports

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World Journal of Clinical Cases 2024年第1期12卷 157-162页

作者： Ling-Zhi Fang Hui-Xin Jin Na Zhao Yu-Pei wu ying-Qin shi Department of Pharmacy Hebei Key Laboratory of Clinical PharmacyHebei General HospitalShijiazhuang 050051Hebei ProvinceChina

BACKGROUND Glucose imbalance is common in total parenteral nutrition(TPN).Hypoglycemia seems to be less frequent than hyperglycemia,but it influences the clinical outcome to a greater extent.Therefore,it should be effectively prevented and treated.However,there is no relevant report on how to treat hypoglycemia caused by TPN in patients with liver cell injury.CASE SUMMARY We present three patients with liver cell injury who developed severe hypo-glycemia during or after TPN infusion.The causes of severe hypoglycemia and glucose-raising strategies were discussed.According to the physiological charac-teristics of the hepatocellular injury,the ratio of nutrition components prescribed in TPN was appropriately adjusted for the three cases.We simultaneously reduced the dose of insulin and fat emulsion,and increased the dose of glucose in TPN.The blood glucose level was restored to normal range and clinical symptoms were eliminated.CONCLUSION When hypoglycemia occurs during or after TPN in patients with hepatocellular injury,physicians need to simultaneously reduce insulin and fat emulsion,and increase glucose,and correct severe hypoglycemia in time to reduce its adverse consequences.

关键词： Total parenteral nutrition Hepatocellular injury Severe hypoglycemia Treatment Causes Case report

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UNIFORM SUPERCONVERGENCE ANALYSIS OF A TWO-GRID MIXED FINITE ELEMENT METHOD FOR THE TIME-DEPENDENT BI-WAVE PROBLEM MODELING D-WAVE SUPERCONDUCTORS

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Journal of Computational Mathematics 2024年第2期42卷 415-431页

作者： Yanmi wu Dongyang shi PLA Information Engineering University Zhengzhou 450001China School of Mathematics and Information Sciences Yantai UniversityYantai 264005China

In this paper,a two-grid mixed finite element method(MFEM)of implicit Backward Euler(BE)formula is presented for the fourth order time-dependent singularly perturbed Bi-wave problem for d-wave superconductors by the nonconforming EQ_(1)^(rot) element.In this approach,the original nonlinear system is solved on the coarse mesh through the Newton iteration method,and then the linear system is computed on the fine mesh with Taylor’s expansion.Based on the high accuracy results of the chosen element,the uniform superclose and superconvergent estimates in the broken H^(1)-norm are derived,which are independent of the negative powers of the perturbation parameter appeared in the considered problem.Numerical results illustrate that the computing cost of the proposed two-grid method is much less than that of the conventional Galerkin MFEM without loss of accuracy.

关键词： Time-dependent Bi-wave problem Two-grid mixed finite element method Uniform superclose and superconvergent estimates

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ELABELA-derived peptide ELA13 attenuates kidney fibrosis by inhibiting the Smad and ERK signaling pathways

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2024年第4期25卷 341-353页

作者： Zhibin YAN ying shi Runling YANG Jijun XUE Caiyun FU Zhejiang Provincial Key Laboratory of Silkworm Bioreactor and Biomedicine College of Life Sciences and MedicineZhejiang Sci-Tech UniversityHangzhou310018China State Key Laboratory of Applied Organic Chemistry College of Chemistry and Chemical EngineeringLanzhou University Lanzhou 730000China Key Laboratory of Preclinical Study for New Drugs of Gansu Province School of Basic Medical Sciences&Research Unit of Peptide ScienceChinese Academy of Medical Sciences2019RU066Lanzhou UniversityLanzhou 730000China

Kidney fibrosis is an inevitable result of various chronic kidney diseases(CKDs)and significantly contributes to end-stage renal failure.Currently,there is no specific treatment available for renal fibrosis.ELA13(amino acid sequence:RRCMPLHSRVPFP)is a conserved region of ELABELA in all vertebrates;however,its biological activity has been very little studied.In the present study,we evaluated the therapeutic effect of ELA13 on transforming growth factor-β1(TGF-β1)-treated NRK-52E cells and unilateral ureteral occlusion(UUO)mice.Our results demonstrated that ELA13 could improve renal function by reducing creatinine and urea nitrogen content in serum,and reduce the expression of fibrosis biomarkers confirmed by Masson staining,immunohistochemistry,real-time polymerase chain reaction(RT-PCR),and western blot.Inflammation biomarkers were increased after UUO and decreased by administration of ELA13.Furthermore,we found that the levels of essential molecules in the mothers against decapentaplegic(Smad)and extracellular signal-regulated kinase(ERK)pathways were reduced by ELA13 treatment in vivo and in vitro.In conclusion,ELA13 protected against kidney fibrosis through inhibiting the Smad and ERK signaling pathways and could thus be a promising candidate for anti-renal fibrosis treatment.

关键词： ELA13 Kidney fibrosis Inflammation Smad Extracllular signal-regulated kinase(ERK)

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Feeding prehistoric coastal community:A study of marine faunal remains at the Jingtoushan site

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Science China Earth Sciences 2024年第5期67卷 1574-1590页

作者： Endong wu Guoping SUN ying ZHANG School of Culture History and LanguageAustralian National UniversityCanberra 2600Australia Zhejiang Provincial Institute of Cultural Relics and Archaeology Hangzhou 310012China National Centre for Archaeology Beijing 100013China

This article examines the abundant marine mollusc,and fish remains at the Jingtoushan shell midden(8,300 to7,800 cal a BP)in Zhejiang Province,China,to investigate the fishing economy,community development,the palaeoenvironment,and their interactions among the prehistoric populations in the lower Yangtze River Basin and southeastern coastal China.It also attempts to explore the prosperity and decline of coastal settlements in China during the Neolithic Age and the potential reasons for their rise and fall,respectively.Based on the ecological and biological principles of marine animals,standard zooarchaeological methods and radiocarbon dating analysis are used for sampling,identification,measurement,and quantification.Results show that at least 11 mollusc taxa and 14 fish taxa can be identified from the Jingtoushan faunal assemblage.The ancient Jingtoushan residents possibly lived in a settlement close to the coast and engaged in inshore and offshore fishing,hunting,and gathering as their primary subsistence strategies,with low-level rice cultivation as a supplementary means of sustenance.Eventually,the changes in the coastal environment could be one of the reasons why the Jingtoushan residents abandoned their settlement.The research contributes to Chinese Neolithic archaeology with new evidence of the exploitation of marine resources around 8000 a BP in the eastern coastal areas and the relationship between Neolithic community development and environmental changes.

关键词： Neolithic Age Marine faunal remains Fishing economy Palaeoenvironment Community development

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