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Partition method for impact dynamics of flexible multibody systems based on contact constraint

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Applied Mathematics and Mechanics(English Edition) 2013年第11期34卷 1393-1404页

作者：段玥晨章定国洪嘉振 School of Mechanical Engineering Zhengzhou University School of Science Nanjing University of Science and Technology Department of Engineering Mechanics Shanghai Jiao Tong University

The impact dynamics of a flexible multibody system is investigated. By using a partition method, the system is divided into two parts, the local impact region and the region away from the impact. The two parts are connected by specific boundary conditions, and the system after partition is equivalent to the original system. According to the rigid-flexible coupling dynamic theory of multibody system, system＇s rigid-flexible coupling dynamic equations without impact are derived. A local impulse method for establishing the initial impact conditions is proposed. It satisfies the compatibility con- ditions for contact constraints and the actual physical situation of the impact process of flexible bodies. Based on the contact constraint method, system＇s impact dynamic equa- tions are derived in a differential-algebraic form. The contact/separation criterion and the algorithm are given. An impact dynamic simulation is given. The results show that system＇s dynamic behaviors including the energy, the deformations, the displacements, and the impact force during the impact process change dramatically. The impact makes great effects on the global dynamics of the system during and after impact.

关键词： flexible multibody system impact dynamics partition method impulse-momentum method contact constraint

How the microenvironment dominated by the distance effect to regulate the FeN_(4)site ORR activity and selectivity?

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Nano Research 2024年第6期17卷 5735-5741页

作者： Peng Li Qingfeng guo Jianrui zhang Ruilin Chen Shujiang ding Yaqiong Su School of Chemistry Engineering Research Center of Energy Storage Materials and Devices of Ministry of EducationNational Innovation Platform(Center)for Industry-Education Integration of Energy Storage TechnologyXi’an Jiaotong UniversityXi’an 710049China Huanghe Science and Technology College Zhengzhou 450063China General Research Institute of Engineering of Gotion High-Tech Hefei 230041China

The distance effect of the doped heteroatoms away from the catalytic centers has rarely been *** this work,we conducted density functional theory calculations to thoroughly investigate the influence of heteroatom(N,P,B,and S atoms)doping distance on the oxygen reduction reaction(ORR)activity of graphene-based FeN_(4)*** uncovered a Sabatier-like relationship between heteroatom doping distance and ORR activity of FeN_(4)*** nearest doping does not significantly improve and even block the ORR activity of FeN_(4)*** ORR activity is achieved when the heteroatoms are 4-5Å(N,P,and S atoms)or 6-7Å(B atoms)away from the Fe *** of electronic structure indicates that distance effect can modulate the local chemical environment of Fe atoms,thereby account for the changes in ORR activity along with the doping distance and doping *** study provides insights into the influence of heteroatom doping on the chemical environment of reaction active centers,and provides the theoretical guidance for controlling the doping distance of heteroatoms to achieve optimal catalytic activity and selectivity.

关键词： distance effect microenvironment heteroatom doping FeN_(4) Sabatier-like relationship structure-activity relationship

SAPO-34 facilitates the formation of benzene,toluene and xylenes in direct syngas conversion over MnCrO_(x)-SAPO-34-ZSM-5

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Science China Chemistry 2024年第2期67卷 732-740页

作者： Shuchi zhang Dengyun Miao Yi ding Mengyuan Li Shujing guo Yujuan zhang Xiulian Pan Xinhe Bao State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian116023China University of Chinese Academy of Sciences Beijing100049China Shaanxi Yanchang Petroleum(Group)Co. Ltd.&Dalian Institute of Chemical Physics Xi’an Clean Energy(Chemical Industry)Research InstituteXi’an710000China

Direct conversion of syngas to aromatics over metal oxide and zeolite(OXZEO) composite catalysts is ***,the selectivity of more valuable products such as benzene,toluene and xylenes(BTX) is limited due to undesired secondary methylation of ***,we report that the introduction of SAPO-34 into MnCrO_(x)-ZSM-5 catalyst enhances significantly the formation of BTX without sacrificing the aromatics *** optimized conditions,the fraction of BTX in aromatics reaches 64.7% versus 28.9% over the catalyst without SAPO-34.A number of model reaction tests and characterizations reveal that SAPO-34 consumes partially the intermediates such as ketene,by converting them to light ***,the methylation of BTX by ketene to heavy aromatics is inhibited over the external acid sites of ZSM-5,leading to an enhanced BTX selectivity in the *** hybrid catalyst provides an efficient method for highly selective synthesis of BTX from syngas.

关键词： selective syngas conversion OXZEO aromatics BTX multi-functional catalysts

Screening for Bioactive Compounds from Mulberry Leaves Combining Bio-Affinity Ultrafiltration with α-Glucosidase and Pancreatic Lipase

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Journal of Analysis and Testing 2024年第03期8卷 315-326页

作者： Hui zhang Guilin Chen Yongli zhang Felix Wambua Muema Jun ding Mingquan guo CAS Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture Wuhan Botanical Garden Chinese Academy of Sciences University of Chinese Academy of Sciences Institute of Biomedical Engineering Ningbo Institute of Materials Technology and Engineering Chinese Academy of Sciences Ningbo Cixi Institute of Biomedical Engineering

With the growing prevalence of diabetes and obesity worldwide, the role of α-glucosidase and lipase inhibitors has gained increasing concentration. Mulberry, a functional medicinal and edible plant, has been reported extensively in alleviating both diabetes and obesity. However, there is still a lack of refined research on its active ingredients and mechanisms. In our study, the inhibitory activities of mulberry leaf against α-glucosidase and pancreatic lipase reached 191.37 ± 14.46 and 775 ± 68.60 μg/mL, respectively. Meanwhile, it also promoted glucose consumption in the HepG2 cells model. Subsequently,four α-glucosidase ligands and four pancreatic lipase ligands were identified through bio-affinity ultrafiltration combined with liquid-chromatography-mass spectrometry(UF-HPLC–MS/MS). In vitro inhibition assays confirmed the inhibitory potential of these representative ligands. Molecular docking suggested that these possible ligands could be inserted into the active pocket of the target enzyme through multiple intermolecular forces. Our findings indicated that the polyphenols in mulberry leaves may contribute significantly to their hypoglycemic and hypolipidemic properties. Furthermore, our study provides valuable insights for the screening of active ingredients in other medicinal and edible plants, which could help in the development of new therapies for diabetes and obesity.

关键词： Bio-affinity ultrafiltration Diabetes Mulberry leaves Obesity

Endoloop ligation after endoscopic mucosal resection using a transparent cap: A novel method to treat small rectal carcinoid tumors

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World Journal of Gastroenterology 2019年第10期25卷 1259-1265页

作者： ding-guo zhang Su Luo Feng Xiong Zheng-Lei Xu Ying-Xue Li Jun Yao Li-Sheng Wang Department of Gastroenterology Shenzhen People’s HospitalFirst Affiliated Hospital of Southern University of Science and TechnologySecond Clinical Medical College of Jinan University

BACKGROUND Local endoscopic resection is an effective method for the treatment of small rectal carcinoid tumors, but remnant tumor at the margin after resection remains to be an *** To evaluate the efficacy and safety of resection of small rectal carcinoid tumors by endoloop ligation after cap-endoscopic mucosal resection(LC-EMR) using a transparent *** Thirty-four patients with rectal carcinoid tumors of less than 10 mm in diameter were treated by LC-EMR(n = 22) or endoscopic submucosal dissection(ESD)(n =12) between January 2016 and December 2017. Demographic data, complete resection rates, pathologically complete resection rates, operation duration, and postoperative complications were collected. All cases were followed for 6 to 30 *** A total of 22 LC-EMR cases and 12 ESD cases were enrolled. The average age was48.18 ± 12.31 and 46.17 ± 12.57 years old, and the tumor size was 7.23 ± 1.63 mm and 7.50 ± 1.38 mm, respectively, for the LC-EMR and ESD groups. Resection time in the ESD group was longer than that in the LC-EMR group(15.67 ± 2.15 min vs 5.91 ± 0.87 min; P ding was observed in either *** complete resection(P-CR) rate was 86.36%(19/22) and 91.67%(11/12) in the LC-EMR and ESD groups(P = 0.646), respectively. Two of the three cases with a positive margin in the LC-EMR group received transanal endoscopic microsurgery(TEM) and tumor cells were not identified in the postoperative specimens. The other case with a positive margin chose follow-up without further operation. One case with remnant tumor after ESD received further local ligation treatment. Neither local recurrence nor lymph node metastasis was found during the follow-up *** LC-EMR appears to be an efficient and simple method for the treatment of small rectal carcinoid tumors, which can effectively avoid margin remnant tumors.

关键词： Rectal carcinoid Endoscopic submucosal dissection Endoscopic mucosal resection Ligation

Alterations in nasal microbiota of patients with amyotrophic lateral sclerosis

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Chinese Medical Journal 2024年第2期137卷 162-171页

作者： Kaixiong Liu Qifu guo Ying ding Li Luo Jianchai Huang Qijie zhang Department of Respiratory and Critical Care Medicine The First Affiliated HospitalFujian Medical UniversityFuzhouFujian 350005China Department of Respiratory and Critical Care MedicineNational Regional Medical CenterBinhai Campus of The First Affiliated HospitalFujian Medical UniversityFuzhouFujian 350212China Department of Neurology Fujian Institute of NeurologyThe First Affiliated HospitalFujian Medical UniversityFuzhouFujian 350005China Department of NeurologyNational Regional Medical CenterBinhai Campus of The First Affiliated HospitalFujian Medical UniversityFuzhouFujian 350212China

Background:Links between alterations in gut microbiota composition and amyotrophic lateral sclerosis(ALS)have previously been *** study aimed to examine the microbiota in the nasal cavity of ***:Sixty-six ALS patients and 40 healthy caregivers who live in close proximity with patients were *** throughput metagenomic sequencing of the 16S ribosomal deoxyribonucleic acid(rDNA)gene V3-V4 region of nasal microbiota was used to characterize the alpha and beta diversity and relative abundance of bacterial taxa,predict function,and conduct correlation analysis between specific taxa and clinical ***:The nasal microbiome of ALS patients showed lower alpha diversity than that of corresponding healthy family *** Gaiella,Sphingomonas,Polaribacter_1,Lachnospiraceae_NK4A136_group,Klebsiella,and Alistipes were differentially enriched in ALS patients compared to *** microbiota composition in ALS patients significantly differed from that in healthy subjects(unweighted UniFrac P=0.001),while Linear discriminant analysis Effect Size(LEfSe)analysis indicated that Bacteroidetes and Firmicutes dominated healthy nasal communities at the phylum level,whereas Actinobacteria was the predominant phylum and Thermoleophilia was the predominant class in ALS *** Faecalibacterium and Alistipes were positively correlated with ALS functional rating scale revised(ALSFRS-R;r_(s)=0.349,P=0.020 and r_(s)=0.393,P=0.008),while Prevotella-9 and Bacteroides operational taxonomic units(OTUs)were positively associated with lung function(FVC)in ALS patients(r_(s)=0.304,P=0.045,and r_(s)=0.300,P=0.048,respectively).Prevotella-1 was positively correlated with white blood cell counts(WBC,r_(s)=0.347,P=0.021),neutrophil percentage(Neu%,r_(s)=0.428,P=0.004),and neutrophil-to-lymphocyte ratio(NLR,r_(s)=0.411,P=0.006),but negatively correlated with lymphocyte percentage(Lym%,r_(s)=-0.408,P=0.006).In contrast,Streptococcus was negatively associa

关键词： Amyotrophic lateral sclerosis Nasal microbiota Dysbiosis Inflammation

Using posterior part of the deltoid muscle as receptor and quality control with intra-operative electrophysiological examination in targeted muscle reinnervation for high-level upper extremity amputees

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Chinese Medical Journal 2021年第9期134卷 1129-1131页

作者： Hua-Wei Yin Jun-Tao Feng Yun-Dong Shen Yan-Song Wang ding-guo zhang Wen-Dong Xu Department of Hand Surgery Huashan HospitalShanghai Medical CollegeFudan UniversityShanghai 200040China Department of Hand and Upper Extremity Surgery Jing'an District Central HospitalShanghai 200040China National Clinical Research Center for Aging and Medicine Huashan HospitalFudan UniversityShanghai 200040China State Key Laboratory of Mechanical System and Vibration School of Mechanical EngineeringShanghai Jiao Tong UniversityShanghai 200240China Priority Among Priorities of Shanghai Municipal Clinical Medicine Center Shanghai 200240China lnstitute of Engineering and Application Technology Fudan UniversityShanghai 200433China

To the Editor:Targeted muscle reinnervation(TMR)is a surgical technique of multiple nerve transfers,providing a potential of improved intuitive prosthetic control via surface electromyography(sEMG)in the high-level upper extremity amputees.[1]However,there is a risk that some of the reinnervations might be unsuccessful,especially for the ulnar nerve.[2]Both the quality control of nerve stumps and the receptor are important factors for the *** the nerve stumps during the surgery and finding more muscles as receptor might address the ***,triceps,and brachialis muscles were mostly chosen as receptors for reinnervation in the trans-humeral *** major and pectoralis minor were mostly chosen as receptors for reinnervation in the shoulder disarticulation patients.

关键词： reinnervation surgery mostly

Harnessing bacteria for tumor therapy:Current advances and challenges

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Chinese Chemical Letters 2024年第2期35卷 97-106页

作者： Lina guo Jinsong ding Wenhu Zhou Xiangya School of Pharmaceutical Sciences Central South UniversityChangsha 410013China Changsha Medical University Academician WorkstationChangsha 410219China Key Laboratory of Biological Nanotechnology of National Health Commission Changsha 410008China

After a century of standstill,bacteria-based tumor therapy has resurged recently benefiting from the revolution of tumor immunotherapy,which provides unique solutions to tackle the obstacles of traditional tumor *** and facultative anaerobes with active tropism can selectively colonize at tumor sites and suppress tumor growth via different mechanisms,serving as attractive tools for tumor treatment either as a monotherapy or combining with other therapies for synergistic anti-tumor *** this critical review,we introduce the recent advances of bacteria-based tumor therapy from the following ***,the general properties of bacteria are reviewed emphasizing on their structural components related to tumor immunotherapy,and the main bacteria that have been used in tumor therapy are ***,the benefits of bacteria for tumor therapy are illustrated,such as tumor targetability,deep penetration,and facile genetic engineering for attenuation,enhanced efficacy,as well as ***,anti-tumor mechanisms of bacteria are summarized,which refer to intrinsic tumoricidal activities,immune activation,bacteria metabolism,and their capability to regulate gut microbiota ***,bacteria could act as carriers to deliver various types of therapeutics to achieve combination therapy with improved *** addition,several challenges for anti-tumor applications of bacteria are discussed regarding the delivery,efficacy and safety issues,and potential solutions are also ***,the possible improvements and perspectives are discussed in the end,which provide a guideline for the design of advanced bacteria-based tumor therapeutics in the future.

关键词： Bacteria Tumor targeting Immunotherapy Combination therapy Genetic engineering Surface decoration

A preliminary study on life history of marine red alga Stylonema alsidii(Zandardini)Drew *** Zheng et Li

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Journal of Oceanology and Limnology 2024年第3期42卷 915-922页

作者： Bingxin HUANG Yao zhang Yue CHU Youxuan guo Junxia LIANG Jianan QIN Lanping ding Tianjin Key Laboratory of Animal and Plant Resistance College of Life SciencesTianjin Normal UniversityTianjin 300387China

Stylonema alsidii(Zandardini)Drew *** Zheng et Li is a common species in the genus Stylonema,but there are limited reports on morphological taxonomy and a lack of studies on life history and the regulation of early *** early development,discoid formation,and erect thallus growth of Stylonema alsidii *** were observed under laboratory *** addition,the influence of main environmental factors such as temperature and light intensity on its development was briefly studied,and various stages of its life history were *** result shows:(1)there are two reproductive modes:asexual reproduction and sexual reproduction;(2)the morphology of this species varies in different degrees under laboratory culture conditions;(3)sexual reproduction and asexual reproduction can coexist under suitable *** pathways of life history were inferred from experimental *** sporophytes form mature gametophytes by producing initially isolated or initially attached monospore,and mature gametophytes form mature sporophytes by fertilization of eggs and *** sexual and asexual reproduction processes of Stylonema alsidii *** were reported for the first time,and this is also the first report on sexual reproduction in the genus Stylonema.

关键词： Stylonema alsidii(Zandardini)Drew f.ramosum Zheng et Li life history environmental factor asexual reproduction sexual reproduction