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Previously unexplored etiology for femoral head necrosis:Metagenomics detects no pathogens in necrotic femoral head tissue

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World Journal of Clinical Cases 2022年第7期10卷 2138-2146页

作者： chao Liu wei Li chao Zhang Feng Pang Da-wei Wang Department of Orthopedics Liaocheng People's HospitalLiaocheng 252000Shandong ProvinceChina Department of Orthopedics Shandong The First Medical UniversityTaian 271016Shandong ProvinceChina Department of Clinical Laboratory Liaocheng People's HospitalLiaocheng 252000Shandong ProvinceChina

BACKGROUND Osteonecrosis of the femoral head(ONFH)is a frequent and refractory disease whose pathogenesis has not yet been *** and other factors that reduce the local blood supply can lead to bone *** To aim of this study was to assess the relationship of ONFH with bone infection by use of metagenomic *** Twelve patients with idiopathic ONFH and 12 comparable controls who were undergoing hip arthroplasty were followed up in *** femoral head specimens were collected for bacterial and fungal cultures using standard *** specimens were subjected to preliminary processing,and metagenomics sequencing of microorganisms was performed.A one-way analysis of variance was used to compare bacterial species in the two *** Bacterial and fungal cultures exhibited no evidence of microbial growth in all isolated necrotic femoral head *** thus performed metagenomic sequencing and classified the species as suspected pathogens or suspected background microorganisms based on known bacterial *** was no evidence of viruses,fungi,parasites,*** complex,or mycoplasma/*** were also no significant differences in suspected pathogens or suspected background microorganisms(P>0.05).CONCLUSION Although we found no pathogens specific for ONFH in necrotic femoral head tissue,our research provides a foundation for future research on the metagenomics of bone pathogens.

关键词： Idiopathic Osteonecrosis of the femoral head Sequencing Pathogens

Akkermansia muciniphila: a promising target for the therapy of metabolic syndrome and related diseases

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Chinese Journal of Natural Medicines 2019年第11期17卷 835-841页

作者： ZHOU Ji-chao ZHANG Xiao-wei Molecular Immunology and Pharmacology Group State Key Laboratory of Bioactive Substance and Function of Natural Medicines Institute of Materia Medica Chinese Academy of Medical Sciences & Peking Union Medical College

The probiotic Akkermansia muciniphila(A. muciniphila) is an intestinal bacterium that was first identified in human feces in 2004. Its specialization in mucin degradation makes it a key microorganism that maintains intestinal mucosal barrier function. As an unique representative strain of the phylum Verrucomicrobia that can be cultured in vitro, A. muciniphila is much easier to detect by metagenomic analysis of intestinal flora. In the past few years, A. muciniphila has been getting increasing attention for the positive correlation between its intestinal colonization and host homeostatic metabolism. In this review, we summarize the relationship between A. muciniphila and host health and diseases, especially focusing on metabolic diseases and related mechanisms, as well as the natural food and drug-derived substrates affecting its colonization in the host, expecting to provide evidence and clues for the development of drugs targeting A. muciniphila.

关键词： Gut microbiota Metabolic syndrome Diabetes Atural medicine

Testing a solar coronal magnetic field extrapolation code with the Titov–Dmoulin magnetic flux rope model

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Research in Astronomy and Astrophysics 2016年第1期16卷 129-134页

作者： chao-wei Jiang Xue-Shang Feng SIGMA Weather Group State Key Laboratory for Space Weather Center for Space Science and Applied Research Chinese Academy of Sciences Beijing 100190 China

In the solar corona, the magnetic flux rope is believed to be a fundamental structure that accounts for magnetic free energy storage and solar eruptions. Up to the present, the extrapolation of the magnetic field from boundary data has been the primary way to obtain fully three-dimensional magnetic information about the corona. As a result, the ability to reliably recover the coronal magnetic flux rope is important for coronal field extrapolation. In this paper, our coronal field extrapolation code is examined with an analytical magnetic flux rope model proposed by Titov ＆ D6moulin, which consists of a bipolar magnetic configuration holding a semi-circular line-tied flux rope in force-free equilibrium. By only using the vector field at the bottom boundary as input, we test our code with the model in a representative range of parameter space and find that the model field can be reconstructed with high accuracy. In particular, the magnetic topological interfaces formed between the flux rope and the surrounding arcade, i.e., the ＂hyperbolic flux tube＂ and ＂bald patch separatrix surface,＂ are also reliably reproduced. By this test, we demonstrate that our CESE-MHD-NLFFF code can be applied to recovering the magnetic flux rope in the solar corona as long as the vector magnetogram satisfies the force-free constraints.

关键词： magnetic fields -- magnetohydrodynamics (MHD) -- methods: numerical -- Sun: corona

Information Flow Scheduling in Concurrent Multi-Product Development Based on DSM

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Chinese Journal of Mechanical Engineering 2017年第5期30卷 1101-1111页

作者： Qing-chao Sun wei-Qiang Huang Ying-Jie Jiang wei Sun School of Mechanical Engineering Dalian University of Technology

Multi-product collaborative development is adopted widely in manufacturing enterprise, while the present multi-project planning models don＇t take techni- cal/data interactions of multiple products into account. To decrease the influence of technical/data interactions on project progresses, the information flow scheduling models based on the extended DSM is presented. Firstly, infor- mation dependencies are divided into four types： series, parallel, coupling and similar. Secondly, different types of dependencies are expressed as DSM units, and the exten- ded DSM model is brought forward, described as a block matrix. Furthermore, the information flow scheduling methods is proposed, which involves four types of opera- tions, where partitioning and clustering algorithm are modified from DSM for ensuring progress of high-priority project, merging and converting is the specific computation of the extended DSM. Finally, the information flow scheduling of two machine tools development is analyzed with example, and different project priorities correspond to different task sequences and total coordination cost. The proposed methodology provides a detailed instruction for information flow scheduling in multi-product development, with specially concerning technical/data interactions.

关键词： Concurrent multi-product development Information flow planning Extended DSM Projectpriority

Electrochem ically Enabled Intram olecular Am inooxygenation of Alkynes v ia Am idyl Radical Cyclization

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Chinese Journal of Chemistry 2020年第4期38卷 394-398页

作者： Zhong-wei Hou Hai-chao Xu State Key Laboratory of Physical Chemistry of Solid Surfaces iChEMKey Laboratory of Chemical Biology of Fujian Provinceand College of Chemistry and Chemical EngineeringXiamen UniversityXiamenFujian 361005Chino

Summary of main observation and conclusion An electrochemical synthesis of oxazol-2-ones and imidazol-2-ones has been developed via 5-exo-dig cyclization of propargylic carbamates-and ureas-derived amidyl *** electrosynthesis relies on the dual function of 2,2,66-tetramethylpiperidin-1-y oxyl(TEMPO)as a redox mediator for amidyl radical formation and an oxygen atom *** reactions are conducted under mild conditions using a simple setup and provide convenient access to functionalized oxazol-2-ones and imidazol-2-ones from readily available materials.

关键词： materials. donor readily

Effects of Shell Composition, Dosage and Alkali Type on the Morphology of Polymer Hollow Microspheres

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Chinese Journal of Polymer Science 2018年第1期36卷 43-48页

作者： wei Deng Hua-chao Guo wei-Li Yu Cheng-You Kan Key Laboratory of Engineering Dielectrics and Its Application Ministry of Education School of Material Science and Engineering Harbin University of Science and Technology Department of Chemical Engineering Key Laboratory of Advanced Materials of Ministry of Education Tsinghua University

Polymer hollow microspheres were prepared by performing alkali treatment on the multilayer core/shell polymer latex particles containing carboxyl groups. Effects of the shell composition and dosage as well as alkali type on the morphology of the microspheres were investigated. Results showed that in comparison with acrylonitrile（AN） and methacrylic acid（MAA）, using butyl acrylate（BA） as the shell co-monomer decreased the glass transition temperature（T_g） of shell effectively and was beneficial to the formation of uniform and big hollow structure. Along with the increase of the shell dosage, the alkali-treated microspheres sequentially presented porous and hollow morphology, and the size of microspheres increased, while the hollow diameter increased first and then decreased, and the maximum hollow ratio reached 39.5%. Furthermore, the multilayer core/shell microspheres had better tolerance to NH_3·H_2O than to NaOH. When the molar ratio of alkali to methacrylic acid（MR_（alkali/acid）） for Na OH ranged from 1.15 to 1.30 or MRalkali/acid for NH_3·H_2O ranged from 1.30 to 2.00, the regular polymer hollow microspheres could be obtained.

关键词： Hollow microspheres Core-Shell polymer Alkali treatment Morphology

Recent Advances in Homogeneous Carbonylation Using CO_2 as CO Surrogate

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Chinese Journal of Chemistry 2018年第4期36卷 353-362页

作者： Lu Wang wei Sun chao Liu State Key Laboratory for Oxo Synthesis and Selective Oxidation Suzhou Research institute of LICP Lanzhou institute of Chemical Physics (LICP) Chinese Academy of Sciences Lanzhou Gansu 730000 China University of Chinese Academy of Sciences Beijing 100049 China

Carbon dioxide is a sufficient and important carbon resource, which has been widely used as a C1 building block in synthetic chemistry. Car- bonylations with CO are important processes in industry. However, due to the toxicity of CO, its storage and transport are problematic. Attentions are gradually focused on using other safe reagents to be the CO surrogates in carbonylation reactions. This review focuses on the summary of recent devel- opments in using CO_2 as a CO surrogate in homogeneous catalysis. Reductive processes by using H2, Si-H, alcohols, etc and redox-neutral processes are separately summarized.

关键词： carbon dioxide CI source carbonylation homogeneous catalysis

Cu/Picolinamides-Catalyzed Coupling of (Hetero) aryl Halides with Secondary Phosphine Oxides and Phosphite

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Chinese Journal of Chemistry 2021年第11期39卷 2957-2961页

作者： chao Fang Bangguo wei Dawei Ma Department of Natural Medicine School of PharmacyFudan University826 Zhangheng RoadShanghai201203 China State Key Laboratory of Bioorganic&Natural Products Chemistry Center for Excellence in Molecular SynthesisShanghai Institute of Organic ChemistryUniversity of Chinese Academy of SciencesChinese Academy of Sciences345 Lingling LuShanghai200032 China

Some 4-hydroxy-picolinic acid derived amides were revealed as more efficient ligands for Cu-catalyzed coupling of(hetero)aryl halides with secondary phosphine oxides and *** 3—5 mol%CuI and ligands were required to e... 详细信息

关键词： Synthetic methods Cross-Coupling Aryl halides Copper Aryl phosphine oxides

A combined continuous-discontinuous approach for failure process of quasi-brittle materials

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Science China(Technological Sciences) 2014年第3期57卷 550-559页

作者： CHANG XiaoLin HU chao ZHOU wei MA Gang ZHANG chao State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan University

Rock,concrete and other geo-materials,due to the presence of microstructural inhomogeneity,their fracture processes and damage characteristics are associated with the distribution of micro-cracks contained in the *** this study,by introducing a cohesive zone model based on fracture mechanics into the framework of deformable discrete element method,a continuous-discontinuous coupling analysis approach for simulating the fracture of quasi-brittle materials is *** cohesive interface elements are inserted into certain engineering or research *** is assumed that damage and fracture occur only in the interface elements,while bulk material is modeled to be *** Mohr-Coulomb criterion with tension cut-off is adopted as the damage initiation criterion,and a scalar damage variable representing damage in the material is used to describe the rate at which the material stiffness is *** are simulated explicitly by the failure of the interface *** simulations are performed in order to validate the suggested *** applications are also *** results show that this method provides a simple but effective tool for the simulation of crack initiation and propagation,and it can reflect the whole process of quasi-brittle materials from small deformation to large deformation and failure.

关键词： quasi-brittle materials deformable discrete elements cohesive zone model crack propagation