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The Monsky Matrices and Non-congruent Numbers

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Algebra Colloquium 2024年第2期31卷 239-262页

作者： guilin Li Hourong Qin Fei Xu Department of Mathematics Nanjing UniversityNanjing 210093China 不详

We give some sufficient conditions for non-congruent numbers in terms of the Monsky matrices.Many known criteria for non-congruent numbers can be viewed as special cases of our results.

关键词： congruent elliptic curve Selmer group Monsky matrix non-congruent number

Selective synthesis and physical properties of a bismacrocycle:Cycloparaphenylene-pillar[5]arene

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Chinese Chemical Letters 2024年第3期35卷 273-276页

作者： Yu Zhou guilin Zhuang Pingwu Du Key Laboratory of Precision and Intelligent Chemistry Hefei National Laboratory for Physical Sciences at the MicroscaleCAS Key Laboratory of Materials for Energy ConversionDepartment of Materials Science and EngineeringUniversity of Science and Technology of ChinaHefei 230026China College of Chemical Engineering Zhejiang University of TechnologyHangzhou 310032China

Macrocyclic materials have attracted much attention due to their particular chemical and physical properties.Herein we report the precise synthesis and characterization of a new bismacrocycle structure base on cycloparaphenylene(CPP)and pillar[5]arene,named cycloparaphenylene-pillar[5]arenes(CPPn[5]).The bismacrocycle was fully characterized by NMR and HR-MS.The photophysical properties of CPPn[5]were investigated by UV–vis,and the maximum absorption peak was located at 331 nm,which was consistent with density functional theory(DFT)calculations.The fluorescence spectrum was further studied and the emission peak was maximized at 458 nm.The computational results indicate the strain energy of CPPn[5]is 27.80 kcal/mol and the HOMO-LUMO gap is 3.39 eV Notably,CPPn[5]showed interesting supramolecular properties.

关键词： Pillararene Cycloparaphenylene Bismacrocycles Supramolecular chemistry

Numerical Study of the Biomechanical Behavior of a 3D Printed Polymer Esophageal Stent in the Esophagus by BP Neural Network Algorithm

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Computer Modeling in Engineering & Sciences 2024年第3期138卷 2709-2725页

作者： guilin Wu Shenghua Huang Tingting Liu Zhuoni yang Yuesong Wu Guihong Wei Peng Yu Qilin Zhang Jun Feng Bo Zeng College of Civil Engineering and Architecture Key Laboratory of Disaster Prevention and Structural Safety of Ministry of EducationGuangxi Key Laboratory of Disaster Prevention and Structural SafetyScientific Research Center of Engineering MechanicsGuangxi UniversityNanning530004China Anaesthesiology Department of the 923th The 923th Hospital of PLA Joint Logistic Support ForceNanning530021China Biomedical Materials Engineering Research Center Tsinghua Innovation Center in DongguanDongguan523808China Research Centre Guangxi Nanning Ruifeng Medical Devices Co.Ltd.Nanning530000China Department of Thoracic Surgery The First Affiliated HospitalSun Yat-sen UniversityGuangzhou510080China

Esophageal disease is a common disorder of the digestive system that can severely affect the quality of life andprognosis of patients. Esophageal stenting is an effective treatment that has been widely used in clinical practice.However, esophageal stents of different types and parameters have varying adaptability and effectiveness forpatients, and they need to be individually selected according to the patient’s specific situation. The purposeof this study was to provide a reference for clinical doctors to choose suitable esophageal stents. We used 3Dprinting technology to fabricate esophageal stents with different ratios of thermoplastic polyurethane (TPU)/(Poly-ε-caprolactone) PCL polymer, and established an artificial neural network model that could predict the radial forceof esophageal stents based on the content of TPU, PCL and print parameter. We selected three optimal ratios formechanical performance tests and evaluated the biomechanical effects of different ratios of stents on esophagealimplantation, swallowing, and stent migration processes through finite element numerical simulation and in vitrosimulation tests. The results showed that different ratios of polymer stents had different mechanical properties,affecting the effectiveness of stent expansion treatment and the possibility of postoperative complications of stentimplantation.

关键词： Finite element method 3D printing polymer esophageal stent artificial neural network

Chiral transfer amidst one-dimensional linear polymers and twodimensional network covalent organic frameworks:Striking a fine balance between helicity and crystallinity

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Nano Research 2024年第6期17卷 5726-5734页

作者： Xinlin Zha Mengjuan Zuo guilin Xu Zhong Yan Haining You Yi Xiong Ying Liu Yingying Li Liyan yang Ke Liu Mufang Li Tao Zhao Dong Wang College of Chemistry and Chemical Engineering Donghua UniversityShanghai 201620China Key Laboratory of Textile Fiber and Products Ministry of EducationWuhan Textile UniversityWuhan 430200China

The current landscape of chiral covalent organic frameworks(COFs)predominantly centered on constructing asymmetric molecular-scale chirality,often introducing an inherent contradiction to the COF symmetry and limiting diversity.Herein,we overcome these challenges by achieving chiral transfer between one-dimensional(1D)imine linear polymers(LPs)and two-dimensional(2D)networkβ-ketoenamine COFs composed of achiral monomers.We successfully synthesize several 1D imine LPs with mesoscopic helical chirality,comprising achiral C2-symmetric terephthalaldehyde and diamine linkers in a chiral supramolecular transcription system.Leveraging the irreversible tautomerism mechanism within the linker replacement approach,terephthalaldehyde(TPA)units in these helical 1D LPs are substituted with C3-symmetric 1,3,5-triformylphloroglucinol(TP),yielding the corresponding 2D networkβ-ketoenamine COFs.Crystallinity and helicity of the resultantβ-ketoenamine COFs intimately hinge on reaction conditions,including the aldehyde stoichiometry of Tp and TPA,as well as the quantity and concentration of the catalyst employed.Under optimized conditions,the nucleation and growth were precisely governed,achieving a harmonious equilibrium of crystallinity and helicity within the generated 2D networkβ-ketoenamine COFs,even with covalent bond rupture,recombination,and topological transition(from[C2+C2]to[C3+C2]).Impressively,the ground state chirality inherent to helical 1D LPs seamlessly transfers to helical 2D networkβ-ketoenamine COFs.This study not only offers new perspectives on the development of chiral functional COFs,but also provides fresh insights into the precise control of COFs'microscopic morphology.

关键词： chiral covalent organic frameworks chiral transfer dimensional transformation helicity

State-of-the-art on theories and applications of cable-driven parallel robots

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Frontiers of Mechanical Engineering 2022年第3期17卷 35-57页

作者： Zhaokun ZHANG Zhufeng SHAO Zheng YOU Xiaoqiang TANG Bin ZI guilin yang Clément GOSSELIN Stéphane CARO State Key Laboratory of Tribology Department of Mechanical EngineeringTsinghua UniversityBeijing 100084China Beijing Key Laboratory of Precision/Ultra-Precision Manufacturing Equipment and Control Tsinghua UniversityBeijing 100084China Department of Mechanical Engineering University of MichiganAnn ArborMI 48109USA Department of Precision Instrument Tsinghua UniversityBeijing 100084China School of Mechanical Engineering Hefei University of TechnologyHefei 230009China Ningbo Institute of Industrial Technology Chinese Academy of Sciences(CAS)Ningbo 315201China Department of Mechanical Engineering UniversitéLavalQuebec QC G1V 0A6Canada Laboratory of Digital Sciences of Nantes National Centre for Scientific ResearchNantes 44321France

Cable-driven parallel robot(CDPR)is a type of high-performance robot that integrates cable-driven kinematic chains and parallel mechanism theory.It inherits the high dynamics and heavy load capacities of the parallel mechanism and significantly improves the workspace,cost and energy efficiency simultaneously.As a result,CDPRs have had irreplaceable roles in industrial and technological fields,such as astronomy,aerospace,logistics,simulators,and rehabilitation.CDPRs follow the cutting-edge trend of rigid-flexible fusion,reflect advanced lightweight design concepts,and have become a frontier topic in robotics research.This paper summarizes the kernel theories and developments of CDPRs,covering configuration design,cable-force distribution,workspace and stiffness,performance evaluation,optimization,and motion control.Kinematic modeling,workspace analysis,and cable-force solution are illustrated.Stiffness and dynamic modeling methods are discussed.To further promote the development,researchers should strengthen the investigation in configuration innovation,rapid calculation of workspace,performance evaluation,stiffness control,and rigid-flexible coupling dynamics.In addition,engineering problems such as cable materials,reliability design,and a unified control framework require attention.

关键词： cable-driven parallel robot kinematics optimization dynamics control

Clinical features, treatment strategies and outcomes of craniocervical junction arteriovenous fistulas: a cohort study of 193 patients

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Stroke & Vascular Neurology 2024年第1期9卷 18-29页

作者： Yongjie Ma Zihao Song Yinqing Wang Jiachen Wang Chuan He guilin Li Peng Zhang Tao Hong Liyong Sun Peng Hu Ming Ye Hongqi Zhang Department of Neurosurgery Xuanwu Hospital Capital Medical University

Background Craniocervical junction(CCJ)arteriovenous fistulas(AVFs)are rare.The current treatment strategies for AVFs with different angioarchitecture need to be clarified.The present study aimed to analyse the correlation between angioarchitecture and clinical characteristics,share our experience in treating this disease and identify risk factors associated with subarachnoid haemorrhage(SAH)and poor outcomes.Methods A total of 198 consecutive patients with CCJ AVFs from our neurosurgical centre were retrospectively reviewed.The patients were grouped according to their clinical manifestations,and their baseline clinical characteristics,angioarchitecture,treatment strategies and outcomes were summarised.Results The patients’median age was 56 years(IQR 47–62 years).The majority of patients were men with 166(83.8%)patients.The most common clinical manifestation was SAH(52.0%),followed by venous hypertensive myelopathy(VHM)(45.5%).The most common CCJ AVFs type was dural AVF,with 132(63.5%)fistulas.The most frequent fistula location was C-1(68.7%)and dural branch of vertebral artery(70.2%)was the most involved arterial feeders for fistulas.The most common direction of venous drainage was descending intradural drainage(40.9%),followed by ascending intradural drainage(36.5%).Microsurgery was the most common treatment strategy applied for 151(76.3%)patients,15(7.6%)patients were treated with interventional embolisation only,and 27(13.6%)received both interventional embolisation and microsurgical treatment.The learning curve for microsurgery only was analysed by cumulative summation method,and the turning point was the 70th case,and blood loss in post-group was lower than that in pre-group(p=0.034).At the last follow-up,there were 155(78.3%)patients with favourable outcomes(modified Rankin Scale(mRS)<3).Age≥56(OR 2.038,95%CI 1.039 to 3.998,p=0.038),VHM as the clinical manifestation(OR 4.102,95%CI 2.108 to 7.982,p<0.001)and pretreatment mRS≥3(OR 3.127,95%CI 1.617 to 6.047,p<0.001)were significantly associated with poor out

关键词： patients treatment hypertensive

A linear relationship between De Ritis ratio and mortality in hospitalized patients with COVID-19:A secondary analysis based on a large retrospective cohort study

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iLIVER 2022年第3期1卷 169-175页

作者： Yanling Fu Shouwen Du Xiaodi Liu Lin Cao guilin yang Hongtao Chen From the Department of Infectious Diseases Shenzhen People's Hospital(The Second Clinical Medical CollegeJinan UniversityThe First Affiliated HospitalSouthern University of Science and Technology)Shenzhen 518020GuangdongChina

Background and aims:Although some studies have identified a possible link between the De Ritis ratio and the mortality of patients with COVID-19),the predictive value and the optimal cut-value remain unclear.This study aimed to explore the correlation between the De Ritis ratio and mortality in hospitalized COVID-19.Methods:The data for this cohort study came from a retrospective cohort study that was carried out in a medical system in New York City.The primary outcome was the in-hospital mortality of included patients.The researchers ran multivariate Cox regression analyses,curve fitting,and subgroup analysis to support our findings.Overall survival in different De Ritis ratio groups was plotted as Kaplan-Meier survival curves.Results:The study enrolled 4371 participants with COVID-19 from March 1,2020 to April 16,2020.The overall mortality was 24.8%(1082/4371).The curve fitting analyses indicated that the De Ritis ratio has a positive linear connection with mortality in patients with COVID-19.After adjusting for all covariates,participants with a De Ritis ratio≥2 exhibited 1.29 times the risk of in-hospital mortality compared with those with a De Ritis ratio<1(hazard ratio 1.29,95%confidence interval 1.02-1.62,p=0.031).The p for trend was<0.05 for all models.Patients in the group with a De Ritis ratio≥2 experienced the shortest survival time in the Kaplan-Meier survival analysis.Conclusions:A higher baseline De Ritis ratio is correlated with a corresponding higher mortality among hospitalized people with COVID-19.

关键词： De Ritis ratio COVID-19 Mortality Linear relationship Dryad database

Selective nano-buckling improves the performance of graphene logic transistors

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National Science Review 2024年第2期11卷 95-96页

作者： Tong yang Ming yang Department of Applied Physics The Hong Kong Polytechnic University Research Centre for Nanoscience and Nanotechnology The Hong Kong Polytechnic University

The massive integration of silicon-based transistors into modern electronic devices greatly increases power consumption and heat generation/dissipation[1]. In this concern, transistors based on atomically-thin graphene that exhibit high electric and thermoelectric conductivities with negligible contact resistance,

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Deep Insight of Design,Mechanism,and Cancer Theranostic Strategy of Nanozymes

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Nano-Micro Letters 2024年第2期16卷 165-217页

作者： Lu yang Shuming Dong Shili Gai Dan yang He Ding Lili Feng Guixin yang Ziaur Rehman Piaoping yang Key Laboratory of Superlight Materials and Surface Technology Ministry of EducationCollege of Materials Science and Chemical EngineeringHarbin Engineering UniversityHarbin 150001People’s Republic of China Yantai Research Institute Harbin Engineering UniversityYantai 264000People’s Republic of China Key Laboratory of Green Chemical Engineering and Technology of Heilongjiang Province College of Material Science and Chemical EngineeringHarbin University of Science and TechnologyHarbin 150040People’s Republic of China Department of Chemistry Quaid-i-Azam UniversityIslamabad 45320Pakistan

Since the discovery of enzyme-like activity of Fe3O4 nanoparticles in 2007,nanozymes are becoming the promising substitutes for natural enzymes due to their advantages of high catalytic activity,low cost,mild reaction conditions,good stability,and suitable for large-scale production.Recently,with the cross fusion of nanomedicine and nanocatalysis,nanozyme-based theranostic strategies attract great attention,since the enzymatic reactions can be triggered in the tumor microenvironment to achieve good curative effect with substrate specificity and low side effects.Thus,various nanozymes have been developed and used for tumor therapy.In this review,more than 270 research articles are discussed systematically to present progress in the past five years.First,the discovery and development of nanozymes are summarized.Second,classification and catalytic mechanism of nanozymes are discussed.Third,activity prediction and rational design of nanozymes are focused by highlighting the methods of density functional theory,machine learning,biomimetic and chemical design.Then,synergistic theranostic strategy of nanozymes are introduced.Finally,current challenges and future prospects of nanozymes used for tumor theranostic are outlined,including selectivity,biosafety,repeatability and stability,in-depth catalytic mechanism,predicting and evaluating activities.

关键词： Nanozymes Classification Prediction and design Catalytic mechanism Tumor theranostics