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Effect of solvent on the initiation mechanism of living anionic polymerization of styrene:A computational study

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Chinese Journal of Chemical Engineering 2024年第5期69卷 135-142页

作者： Shen Li Yin-Ning Zhou Zhong-Xin Liu Zheng-hong luo School of Chemical Engineering and Technology Hainan UniversityHaikou 570228China Department of Chemical Engineering School of Chemistry and Chemical EngineeringState Key Laboratory of Metal Matrix CompositesShanghai Jiao Tong UniversityShanghai 200240China

For living anionic polymerization(LAP),solvent has a great influence on both reaction mechanism and kinetics.In this work,by using the classical butyl lithium-styrene polymerization as a model system,the effect of solvent on the mechanism and kinetics of LAP was revealed through a strategy combining density functional theory(DFT)calculations and kinetic modeling.In terms of mechanism,it is found that the stronger the solvent polarity,the more electrons transfer from initiator to solvent through detailed energy decomposition analysis of electrostatic interactions between initiator and solvent molecules.Furthermore,we also found that the stronger the solvent polarity,the higher the monomer initiation energy barrier and the smaller the initiation rate coefficient.Counterintuitively,initiation is more favorable at lower temperatures based on the calculated results ofΔG_(TS).Finally,the kinetic characteristics in different solvents were further examined by kinetic modeling.It is found that in benzene and n-pentane,the polymerization rate exhibits first-order kinetics.While,slow initiation and fast propagation were observed in tetrahydrofuran(THF)due to the slow free ion formation rate,leading to a deviation from first-order kinetics.

关键词： Living anionic polymerization Solvent effect Reaction kinetics Computational chemistry Mathematical modeling Kinetic modeling

Morphology Study for GeV Emission of Nearby Supernova Remnant G332.5-5.6

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Research in Astronomy and Astrophysics 2024年第4期24卷 134-140页

作者： Ming-hong luo Qing-Wen Tang Xiu-Rong Mo Department of Physics School of Physics and Materials ScienceNanchang UniversityNanchang 330031China

A spatial template is important to study nearby supernova remnants(SNRs).For SNR G332.5-5.6,we report a Gaussian disk with a radius of about 1°.06 to be a potential good spatial model in the γ-ray band.Employing this new Gaussian disk,its GeV lightcurve shows a significant variability of about seven sigma.The γ-ray observations of this SNR could be explained well either by a leptonic model or a hadronic model,in which a flat spectrum for the ejected electrons/protons is required.

关键词： ISM:supernova remnants gamma rays:ISM

Genomics,transcriptomics,and peptidomics of the greater wax moth Galleria mellonella neuropeptides and their expression in response to lead stress

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Insect Science 2024年第3期31卷 773-791页

作者： Li-Lin luo Yang Lin Jun-hong Linghu Wei Gong Yuan-hong luo Man Liu Dao-Chao Jin Guy Smagghe Tong-Xian Liu Shun-Hua Gui Tian-Ci Yi Guizhou Provincial Key Laboratory for Agricultural Pest Management of the Mountainous Region Institute of EntomologyGuizhou UniversityGuiyangGuizhouChina Guizhou Institute of Biology Guizhou Academy of SciencesGuiyangChina Institute of Plant Health and Medicine Guizhou UniversityGuiyangChina

Neuropeptides are crucial in regulation of a rich variety of developmental,physiological,and behavioral functions throughout the life cycle of insects.Using an integrated approach of multiomics,we identified neuropeptide precursors in the greater wax moth Galleria mellonella,which is a harmful pest of honeybee hives with a worldwide distribution.Here,a total of 63 and 67 neuropeptide precursors were predicted and annotated in the G.mellonella genome and transcriptome,in which 40 neuropeptide precursors were confirmed in the G.mellonella peptidome.Interestingly,we identified 12 neuropeptide precursor genes present in G.mellonella but absent in honeybees,which may be potential novel pesticide target sites.Honeybee hives were contaminated with heavy metals such as lead,enabling its bioaccumulation in G.mellonella bodies through the food chain,we performed transcriptome sequencing to analyze the effects of Pb stress on the mRNA expression level of G.mellonella neuropeptide precursors.After treatment by Pb,the expression of neuropeptide F1 was found to be significantly downregulated,implying that this neuropeptide might be associated with responding to the heavy metal stress in G.mellonella.This study comprehensively identified neuropeptide precursors in G.mellonella,and discussed the effects of heavy metals on insect neuropeptides,with the example of G.mellonella.The results are valuable for future elucidation of how neuropeptides regulate physiological functions in G.mellonella and contribute to our understanding of the insect's environmental plasticity and identify potential new biomarkers to assess heavy metal toxicity in insects.

关键词： Galleria mellonella genomics heavy metal stress neuropeptide peptidomics transcriptomics

Gastrointestinal contrast-enhanced ultrasonography for diagnosis and treatment of peptic ulcer in children

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World Journal of Gastroenterology 2024年第7期30卷 705-713页

作者： Yu-Hua Zhang Zhi-Hua Xu Shuang-Shuang Ni hong-Xia luo Department of Ultrasound The Second Affiliated Hospital of Wenzhou Medical UniversityWenzhou 325000Zhejiang ProvinceChina

BACKGROUND The detection rate of peptic ulcer in children is improving,with development of diagnostic procedures.Gastroscopy is the gold standard for the diagnosis of peptic ulcer,but it is an invasive procedure.Gastrointestinal contrast-enhanced ultrasonography(CEUS)has the advantages of being painless,noninvasive,nonradioactive,easy to use,and safe.AIM To investigate the clinical value of CEUS for diagnosis and treatment of peptic ulcer in children.METHODS We investigated 43 children with digestive tract symptoms in our hospital from January 2021 to June 2022.All children were examined by routine ultrasound,gastrointestinal CEUS,and gastroscopy.The pathological results of gastroscopy were taken as the gold standard.Routine ultrasonography was performed before gastrointestinal CEUS.Conventional ultrasound showed the thickness of the gastroduodenal wall,gastric peristalsis,and the adjacent organs and tissues around the abdominal cavity.Gastrointestinal CEUS recorded the thickness of the gastroduodenal wall;the size,location and shape of the ulcer;gastric peristalsis;and adjacent organs and tissues around the abdominal cavity.The results of routine ultrasound and gastrointestinal ultrasound were compared with those of gastroscopy to evaluate the diagnostic results and coincidence rate of routine ultrasound and gastrointestinal CEUS.All children received informed consent from their guardians for CEUS.This study was reviewed and approved by the hospital medical ethics committee.RESULTS Among the 43 children,17(15 male,2 female)were diagnosed with peptic ulcer by gastroscopy.There were 26 children with nonpeptic ulcer.There were eight cases of peptic ulcer and 35 of nonpeptic ulcer diagnosed by conventional ultrasound.The diagnostic coincidence rate of peptic ulcer in children diagnosed by conventional ultrasound was 79.1%(34/43),which was significantly different from that of gastroscopy(P=0.033).It indicates that the coincidence rate of gastrointestinal contrast-enhanced ultrasound and gastroscope is low.Fifteen cas

关键词： Contrast-enhanced ultrasound Peptic ulcer Children Gastrointestinal tract Abdominal pain Acoustic contrast agent

Controlling reversible complexation-mediated polymerization(RCMP) via deep eutectic solvents: fast kinetics, narrow molecular weight distribution and mechanistic insights

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Science China Chemistry 2024年第8期67卷 2728-2736页

作者： Xin Fu Zhen Lu Shen Li Zheng-hong luo Lin-Xi Hou Department of Materials-Oriented Chemical Engineering College of Chemical Engineering Fuzhou University Qingyuan Innovation Laboratory Department of Chemical Engineering School of Chemistry and Chemical Engineering State Key Laboratory of Metal Matrix CompositesShanghai Jiao Tong University Chemical Engineering Zhicheng College of Fuzhou University

The exploitation of new green polymerization avenues for the effective synthesis of polymers by reversible-deactivation radical polymerization plays a critical role in pursuing the development of polymeric materials. In this work, serials of deep eutectic solvents(DES) with intermolecular-hydrogen-bonding interaction were constructed as catalysts and medium for actuating reversible complexation-mediated polymerization(RCMP) for the first time, yielding methacrylate polymers with high monomer conversion and narrow dispersion molecular weight in both water and oil systems. The mechanism and elementary reaction of RCMP were explored deeply, revealing that the complexation of initiator with DES to generate radicals was a ratecontrolling step and intermolecular-hydrogen-bond was primary factor to influence polymerization rate. Moreover, the insights of density functional theory calculations revealed that negative electrostatic potential ensured nucleophilic capacity. This investigation demonstrated the considerable potential of DES for RCMP, which is anticipated for other polymerization applications as a novel medium mode.

关键词： deep eutectic solvent density functional theory elementary reaction steps intermolecular hydrogen bonding reversible complexation-mediated polymerization

Role of extracellular vesicles in lung diseases

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Chinese Medical Journal 2022年第15期135卷 1765-1780页

作者： Li Zhou hong luo Jae Woo Lee Department of Pulmonary and Critical Care Medicine The Second Xiangya Hospital of Central South UniversityChangshaHunan 410011China Department of Anesthesiology University of CaliforniaSan FranciscoSan FranciscoCalifornia 94143USA

Extracellular vesicles(EVs)are anuclear particles composed of lipid bilayers that contain nucleic acids,proteins,lipids,and organelles.EVs act as an important mediator of cell-to-cell communication by transmitting biological signals or components,including lipids,proteins,messenger RNAs,DNA,microRNAs,organelles,etc,to nearby or distant target cells to activate and regulate the function and phenotype of target cells.Under physiological conditions,EVs play an essential role in maintaining the homeostasis of the pulmonary milieu but they can also be involved in promoting the pathogenesis and progression of various respiratory diseases including chronic obstructive pulmonary disease,asthma,acute lung injury/acute respiratory distress syndrome,idiopathic pulmonary fibrosis(IPF),and pulmonary artery hypertension.In addition,in multiple preclinical studies,EVs derived from mesenchymal stem cells(EVs)have shown promising therapeutic effects on reducing and repairing lung injuries.Furthermore,in recent years,researchers have explored different methods for modifying EVs or enhancing EVs-mediated drug delivery to produce more targeted and beneficial effects.This article will review the characteristics and biogenesis of EVs and their role in lung homeostasis and various acute and chronic lung diseases and the potential therapeutic application of EVs in the field of clinical medicine.

关键词： Lung diseases Biomarker Lung disease pathogenesis Extracellular vesicles Clinical application

Clinical risk factors for preterm birth and evaluating maternal psychology in the postpartum period

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World Journal of Psychiatry 2024年第5期14卷 661-669页

作者： Jia-Jun Chen Xue-Jin Chen Qiu-Min She Jie-Xi Li Qiu-hong luo Department of Clinical Laboratory Shenzhen Bao’an District Songgang People’s HospitalShenzhen 518000Guangdong ProvinceChina Department of Otolaryngology Head and Neck Surgery Outpatient Shenzhen Children’s HospitalShenzhen 518000Guangdong ProvinceChina Department of Prevention and Health Care Shenzhen Bao’an District Songgang People’s HospitalShenzhen 518000Guangdong ProvinceChina Department of Obstetrics Shenzhen Bao’an District Songgang People’s HospitalShenzhen 518000Guangdong ProvinceChina

BACKGROUND Although the specific pathogenesis of preterm birth(PTB)has not been thoroughly clarified,it is known to be related to various factors,such as pregnancy complications,maternal socioeconomic factors,lifestyle habits,reproductive history,environmental and psychological factors,prenatal care,and nutritional status.PTB has serious implications for newborns and families and is associated with high mortality and complications.Therefore,the prediction of PTB risk can facilitate early intervention and reduce its resultant adverse consequences.AIM To analyze the risk factors for PTB to establish a PTB risk prediction model and to assess postpartum anxiety and depression in mothers.METHODS A retrospective analysis of 648 consecutive parturients who delivered at Shenzhen Bao’an District Songgang People’s Hospital between January 2019 and January 2022 was performed.According to the diagnostic criteria for premature infants,the parturients were divided into a PTB group(n=60)and a full-term(FT)group(n=588).Puerperae were assessed by the Self-rating Anxiety Scale(SAS)and Self rating Depression Scale(SDS),based on which the mothers with anxiety and depression symptoms were screened for further analysis.The factors affecting PTB were analyzed by univariate analysis,and the related risk factors were identified by logistic regression.RESULTS According to univariate analysis,the PTB group was older than the FT group,with a smaller weight change and greater proportions of women who underwent artificial insemination and had gestational diabetes mellitus(P<0.05).In addition,greater proportions of women with reproductive tract infections and greater white blood cell(WBC)counts(P<0.05),shorter cervical lengths in the second trimester and lower neutrophil percentages(P<0.001)were detected in the PTB group than in the FT group.The PTB group exhibited higher postpartum SAS and SDS scores than did the FT group(P<0.0001),with a higher number of mothers experiencing anxiety and depression(P<0.001).Multivariate logistic regression an

关键词： Preterm birth Risk factors Postpartum psychological state Risk model Prediction

High-precision X-ray polarimeter based on channel-cut crystals

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Nuclear Science and Techniques 2024年第3期35卷 30-39页

作者： Shang-Yu Si Zhong-Liang Li Wen-hong Jia Lian Xue hong-Xin luo Jian-Cai Xu Bai-Fei Shen Lin-Gang Zhang Liang-Liang Ji Yu-Xin Leng Ren-Zhong Tai Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China University of Chinese Academy of Sciences Beijing 100049China Shanghai Synchrotron Radiation Facility Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201204China Shanghai Institute of Optics and Fine Mechanics Chinese Academy of SciencesShanghai 201800China

We report on using synthetic silicon for a high-precision X-ray polarimeter comprising a polarizer and an analyzer,each based on a monolithic channel-cut crystal used at multiple Brewster reflections with a Bragg angle very close to 45°.Experiments were performed at the BL09B bending magnet beamline of the Shanghai Synchrotron Radiation Facility using a Si(800)crystal at an X-ray energy of 12.914 keV.A polarization purity of 8.4×10^(-9)was measured.This result is encouraging,as the measured polarization purity is the best-reported value for the bending magnet source.Notably,this is the firstly systematic study on the hard X-ray polarimeter in China,which is crucial for exploring new physics,such as verifying vacuum birefringence.

关键词： X-ray polarimeter Vacuum birefringence Synchrotron radiation Channel-cut crystal

A Trust-Based Hierarchical Consensus Mechanism for Consortium Blockchain in Smart Grid

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Tsinghua Science and Technology 2023年第1期28卷 69-81页

作者： Xingguo Jiang Aidong Sun Yan Sun hong luo Mohsen Guizani School of Computer Science(National Pilot Software Engineering School) Beijing University of Posts and TelecommunicationsBeijing 100876China Institute of Food safety and Nutrition Jiangsu Academy of Agricultural SciencesNanjing 210000China Computer Science and Engineering Department Qatar UniversityDoha 2713Qatar

As the smart grid develops rapidly,abundant connected devices offer various trading data.This raises higher requirements for secure and effective data storage.Traditional centralized data management does not meet the above requirements.Currently,smart grid with conventional consortium blockchain can solve the above issues.However,in the face of a large number of nodes,existing consensus algorithms often perform poorly in terms of efficiency and throughput.In this paper,we propose a trust-based hierarchical consensus mechanism(THCM)to solve this problem.Firstly,we design a hierarchical mechanism to improve the efficiency and throughput.Then,intra-layer nodes use an improved Raft consensus algorithm and inter-layer nodes use the Byzantine Fault Tolerance algorithm.Thirdly,we propose a trust evaluation method to improve the election process of Raft.Finally,we implement a prototype system to evaluate the performance of THCM.The results demonstrate that the consensus efficiency is improved by 19.8%,the throughput is improved by 12.34%,and the storage is reduced by 37.9%.

关键词： consortium blockchain consensus algorithm trust evaluation method smart grid Internet of Things(IoT)