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Inverse reliability analysis and design for tunnel face stability considering soil spatial variability

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第5期16卷 1552-1564页

作者： Zheming Zhang Jian Ji Xiangfeng Guo Siang Huat goh Key laboratory of Ministry of Education for Geomechanics and Embankment Engineering Hohai UniversityNanjing210098China Department of Civil and Environmental Engineering National University of SingaporeSingapore

The traditional deterministic analysis for tunnel face stability neglects the uncertainties of geotechnical parameters,while the simplified reliability analysis which models the potential uncertainties by means of random variables usually fails to account for soil spatial variability.To overcome these limitations,this study proposes an efficient framework for conducting reliability analysis and reliability-based design(RBD)of tunnel face stability in spatially variable soil strata.The three-dimensional(3D)rotational failure mechanism of the tunnel face is extended to account for the soil spatial variability,and a probabilistic framework is established by coupling the extended mechanism with the improved Hasofer-lind-Rackwits-Fiessler recursive algorithm(iHlRF)as well as its inverse analysis formulation.The proposed framework allows for rapid and precise reliability analysis and RBD of tunnel face stability.To demonstrate the feasibility and efficacy of the proposed framework,an illustrative case of tunnelling in frictional soils is presented,where the soil's cohesion and friction angle are modelled as two anisotropic cross-correlated lognormal random fields.The results show that the proposed method can accurately estimate the failure probability(or reliability index)regarding the tunnel face stability and can efficiently determine the required supporting pressure for a target reliability index with soil spatial variability being taken into account.Furthermore,this study reveals the impact of various factors on the support pressure,including coefficient of variation,cross-correlation between cohesion and friction angle,as well as autocorrelation distance of spatially variable soil strata.The results also demonstrate the feasibility of using the forward and/or inverse first-order reliability method(FORM)in high-dimensional stochastic problems.It is hoped that this study may provide a practical and reliable framework for determining the stability of tunnels in complex soil strata.

关键词： limit analysis Tunnel face stability Spatial variability HlRF algorithm Inverse reliability method

1,3-Dipolar Cycloaddition of Polycyclic Aromatic Azomethine Ylides and Alkynylbenziodoxoles for Synthesis of Functional Dibenzoullazines

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Chinese Journal of Chemistry 2024年第10期42卷 1079-1083页

作者： Hui Han Glen Wee Zhuan goh Yongxin li Naohiko Yoshikai Shingo Ito Schoolof Chemistry ChemicalEngineering and BiotechnologyNanyang Technoogical University21 Nanyang LinkSingapore 637371Singapore Graduate School of Pharmaceutical Sciences Tohoku UniversitySendai 980-8578Japan

A new family of dibenzoullazine derivatives was synthesized through 1,3-dipolar cycloaddition of polycyclic aromatic azomethine ylides with alkynylbenziodoxoles followed by oxidation.The benziodoxole moiety in the resulting products was used as a versatile linchpin for the synthesis of structurally diverse functional dibenzoullazines that are difficult to access by other synthetic methods.

关键词： Cycloaddition Nitrogen heterocycles Azomethine ylides Hypervalent compounds Dibenzoullazine

An Implementation of Multiscale line Detection and Mathematical Morphology for Efficient and Precise Blood Vessel Segmentation in Fundus Images

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Computers, Materials & Continua 2024年第5期79卷 2565-2583页

作者： Syed Ayaz Ali Shah Aamir Shahzad Musaed Alhussein Chuan Meng goh Khursheed Aurangzeb Tong Boon Tang Muhammad Awais Department of Electrical and Computer Engineering COMSATS University IslamabadAbbottabad CampusAbbottabad22060Pakistan Department of Computer Engineering College of Computer and Information SciencesKing Saud UniversityP.O.Box 51178Riyadh11543Saudi Arabia Faculty of Information and Communication Technology University Tunku Abdul RehmanKampar CampusKampar31900Malaysia Centre for Intelligent Signal and Imaging Research University Teknologi PETRONASBandar Seri IskandarPerak32610Malaysia School of Computing Sciences University of East AngliaNorwichNR47TJUK

Diagnosing various diseases such as glaucoma,age-related macular degeneration,cardiovascular conditions,and diabetic retinopathy involves segmenting retinal blood vessels.The task is particularly challenging when dealing with color fundus images due to issues like non-uniformillumination,low contrast,and variations in vessel appearance,especially in the presence of different pathologies.Furthermore,the speed of the retinal vessel segmentation system is of utmost importance.With the surge of now available big data,the speed of the algorithm becomes increasingly important,carrying almost equivalent weightage to the accuracy of the algorithm.To address these challenges,we present a novel approach for retinal vessel segmentation,leveraging efficient and robust techniques based on multiscale line detection and mathematical morphology.Our algorithm’s performance is evaluated on two publicly available datasets,namely the Digital Retinal Images for Vessel Extraction dataset(DRIVE)and the Structure Analysis of Retina(STARE)dataset.The experimental results demonstrate the effectiveness of our method,withmean accuracy values of 0.9467 forDRIVE and 0.9535 for STARE datasets,aswell as sensitivity values of 0.6952 forDRIVE and 0.6809 for STARE datasets.Notably,our algorithmexhibits competitive performance with state-of-the-art methods.Importantly,it operates at an average speed of 3.73 s per image for DRIVE and 3.75 s for STARE datasets.It is worth noting that these results were achieved using Matlab scripts containing multiple loops.This suggests that the processing time can be further reduced by replacing loops with vectorization.Thus the proposed algorithm can be deployed in real time applications.In summary,our proposed system strikes a fine balance between swift computation and accuracy that is on par with the best available methods in the field.

关键词： line detector vessel detection localization mathematical morphology image processing

Recent advances in graphene-based phase change composites for thermal energy storage and management

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Nano Materials Science 2024年第2期6卷 115-138页

作者： Qiang Zhu Pin Jin Ong Si Hui Angela goh Reuben J.Yeo Suxi Wang Zhiyuan liu Xian Jun loh Institute of Materials Research and Engineering A*STAR(Agency for ScienceTechnology and Research)2 Fusionopolis WayInnovis#08-03138634Singapore Institute of Sustainability for Chemicals Energy and EnvironmentA*STAR(Agency for ScienceTechnology and Research)1 Pesek RoadJurong Island627833Singapore School of Chemistry Chemical Engineering and BiotechnologyNanyang Technological University21 Nanyang Link637371Singapore Shenzhen Institutes of Advanced Technology(SIAT) Chinese Academy of Sciences(CAS)1068 Xueyuan AvenueShenzhen518055China Department of Material Science and Engineering National University of Singapore9 Engineering Drive 1#03-09 EA117575Singapore

Energy storage and conservation are receiving increased attention due to rising global energy demands.Therefore,the development of energy storage materials is crucial.Thermal energy storage(TES)systems based on phase change materials(PCMs)have increased in prominence over the past two decades,not only because of their outstanding heat storage capacities but also their superior thermal energy regulation capability.However,issues such as leakage and low thermal conductivity limit their applicability in a variety of settings.Carbon-based materials such as graphene and its derivatives can be utilized to surmount these obstacles.This study examines the recent advancements in graphene-based phase change composites(PCCs),where graphene-based nanostructures such as graphene,graphene oxide(GO),functionalized graphene/GO,and graphene aerogel(GA)are incorporated into PCMs to substantially enhance their shape stability and thermal conductivity that could be translated to better storage capacity,durability,and temperature response,thus boosting their attractiveness for TES systems.In addition,the applications of these graphene-based PCCs in various TES disciplines,such as energy conservation in buildings,solar utilization,and battery thermal management,are discussed and summarized.

关键词： Phase change material Nanocomposites Solar energy Sustainable energy Thermo-regulation

On the functions of astrocyte-mediated neuronal slow inward currents

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Neural Regeneration Research 2024年第12期19卷 2602-2612页

作者： Balázs Pál Department of Physiology Faculty of MedicineUniversity of DebrecenDebrecenHungary

Slow inward currents are known as neuronal excitatory currents mediated by glutamate release and activation of neuronal extra synaptic N-met hyl-D-aspartate receptors with the contribution of astrocytes.These events are significantly slower than the excitatory postsynaptic currents.Parameters of slow inward currents are determined by seve ral factors including the mechanisms of astrocytic activation and glutamate release,as well as the diffusion pathways from the release site towards the extra synaptic recepto rs.Astrocytes are stimulated by neuronal network activity,which in turn excite neurons,forming an astrocyte-neuron feedback loop.Mostly as a consequence of brain edema,astrocytic swelling can also induce slow inward currents under pathological conditions.There is a growing body of evidence on the roles of slow inward currents on a single neuron or local network level.These events often occur in synchro ny on neurons located in the same astrocytic domain.Besides synchronization of neuronal excitability,slow inward currents also set synaptic strength via eliciting timing-dependent synaptic plasticity.In addition,slow inward currents are also subject to non-synaptic plasticity triggered by long-la sting stimulation of the excitatory inputs.Of note,there might be important regionspecific differences in the roles and actions triggering slow inward currents.In greater networks,the pathophysiological roles of slow inward currents can be better understood than physiological ones.Slow inward currents are identified in the pathophysiological background of autism,as slow inward currents drive early hypersynchrony of the neural networks.Slow inward currents are significant contributors to paroxysmal depolarizational shifts/interictal spikes.These events are related to epilepsy,but also found in Alzheimer's disease,Parkinson's disease,and stroke,leading to the decline of cognitive functions.Events with features overlapping with slow inward currents(excitatory,N-methyl-Daspartate-receptor mediated currents with astrocyti

关键词： astrocyte cortical spreading depolarization gliotransmission glutamate neural synchronization NMDA receptor paroxysmal depolarizational shift slow inward current

Prevalence and risk factors for impaired renal function among Asian patients with nonalcoholic fatty liver disease

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Hepatobiliary & Pancreatic Diseases International 2024年第3期23卷 241-248页

作者： Chao Sun George Boon-Bee goh Wan-Cheng Chow Wah-Kheong Chan Grace lai-Hung Wong Wai-Kay Seto Yi-Hsiang Huang Han-Chieh lin I-Cheng lee Hye Won lee Seung Up Kim Vincent Wai-Sun Wong Jian-Gao Fan Center for Fatty liver Disease Department of GastroenterologyXinhua Hospital Affiliated to Shanghai Jiao Tong University School of MedicineShanghai Key Lab of Pediatric Gastroenterology and NutritionShanghai 200092China Department of Gastroenterology&Hepatology Singapore General HospitalSingaporeSingapore Gastroenterology and Hepatology Unit Department of MedicineFaculty of MedicineUniversity of MalayaKuala LumpurMalaysia Department of Medicine and Therapeutics and State Key laboratory of Digestive Disease The Chinese University of Hong KongHong KongChina Department of Medicine The University of Hong KongHong KongChina Institute of Clinical Medicine National Yang Ming Chiao Tung University School of MedicineTaipeiTaiwanChina Division of Gastroenterology and Hepatology Taipei Veterans General HospitalTaipeiTaiwanChina Faculty of Medicine National Yang Ming Chiao Tung University School of MedicineTaipeiTaiwanChina Department of Internal Medicine Yonsei University College of MedicineSeoulKorea

Background:Nonalcoholic fatty liver disease(NAFlD)is associated with impaired renal function,and both diseases often occur alongside other metabolic disorders.However,the prevalence and risk factors for impaired renal function in patients with NAFlD remain unclear.The objective of this study was to identify the prevalence and risk factors for renal impairment in NAFlD patients.Methods:All adults aged 18-70 years with ultrasound-diagnosed NAFlD and transient elastography examination from eight Asian centers were enrolled in this prospective study.liver fibrosis and cirrhosis were assessed by FibroScan-aspartate aminotransferase(FAST),Agile 3+and Agile 4 scores.Impaired renal function and chronic kidney disease(CKD)were defined by an estimated glomerular filtration rate(eGFR)with value ofl/min/1.73 m^(2) andl/min/1.73 m^(2),respectively,as estimated by the CKD-Epidemiology Collaboration(CKD-EPI)equation.Results:Among 529 included NAFlD patients,the prevalence rates of impaired renal function and CKD were 37.4%and 4.9%,respectively.In multivariate analysis,a moderate-high risk of advanced liver fibrosis and cirrhosis according to Agile 3+and Agile 4 scores were independent risk factors for CKD(Plasma glucose(FPG)and blood pressure were significantly associated with impaired renal function after controlling for the other components of metabolic syndrome(Plycemia,those with prediabetes[FPG≥5.6 mmol/l or hemoglobin A1c(HbA1c)≥5.7%]were more likely to have impaired renal function(Plusions:Agile 3+and Agile 4 are reliable for identifying NAFlD patients with high risk of CKD.Early glycemic control in the prediabetic stage might have a potential renoprotective role in these patients.

关键词： Nonalcoholic fatty liver disease Impaired renal function Agile 3+ Agile 4 Metabolic syndrome

Complex-frequency waves:beat loss and win sensitivity

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light(Science & Applications) 2024年第2期13卷 181-183页

作者： Qingqing Cheng Tao l School of Optical-Electrical and Computer Engineering University of Shanghai for Science and TechnologyShanghai200093China Department of Respiratory Diseases and Critical Medicine Quzhou Hospital Affiliated to Wenzhou Medical UniversityQuzhou324000China National laboratory of Solid State Microstructures College of Engineering and Applied SciencesNanjing UniversityNanjing210093China

Recent experiments have demonstrated that synthesized complex-frequency waves can impart a virtual gain to molecule sensing systems,which can effectively restore information lost due to intrinsic molecular damping.The enhancement notably amplifies the signal of trace molecular vibrational fingerprints,thereby substantially improving the upper limit of sensitivity.

关键词： thereby Complex limit

Cognition and movement in neurodegenerative disorders:a dynamic duo

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Neural Regeneration Research 2024年第10期19卷 2101-2102页

作者： Marit F.l.Ruitenberg Department of Health Medical and NeuropsychologyLeiden UniversityLeidenthe Netherlands leiden Institute for Brain and Cognition Leidenthe Netherlands

People with neurodegenerative disorders often experience problems across a variety of functional domains,including cognition,movement,and psychosocial functioning.The classification of these disorders is based on the phenotypical manifestations that represent the most prominent clinical features.For example,Parkinson's disease and Huntington's disease are typically regarded as movement disorders,whereas Alzheimer's disease(AD) and other dementias are regarded as cognitive disorders.

关键词： disorders Huntington degenerative

Effect of radiative loss mechanisms on FIR thermometric parameters of Nd3+-doped lithium tellurite glasses

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Journal of Rare Earths 2024年第7期42卷 1250-1257页

作者： C.Y.Morassuti A.P.l Silva l.A.O.Nunes S.M.lima l.H.C.Andrade Optical and Photothermal Spectroscopy Group (GEOF) Center for Studies in Natural Resources (CERNA)State University of Mato Grosso do Sul(UEMS) Renato Archer Information Technology Center Institute of Physics of Sao Carlos University of S?o Paulo

Nd3+-doped tellurite glasses are promising materials for thermometers based on the fluorescence intensity ratio（FIR） technique.Nevertheless,at high Nd3+concentrations,energy transfer（ET） processes such as optical reabsorption and cross-relaxation can affect the Nd3+emission,which has been little explored in the literature.Therefore,the present work investigated the use of Nd3+-doped tellurite glass(samples doped with Nd3+at 0.2 mol%,0.5 mol%,2.0 mol%,and 4.0 mol%) in fluorescence thermometers,in the temperature range from 299 to 371 K.The results indicate a strong dependence of the FIR parameters on the Nd3+concentration,due to changes in the emission band profiles caused by optical reabsorption of the Nd3+emissions and cross-relaxation processes.A decrease of the relative sensitivity of the ratio4F5/2→4I9/2/4F3/2→4I9/2is observed for samples doped with higher amounts of Nd3+.The maximum relative sensitivity at 299 K is 3.00%/K,which is the highest value among the reported Nd3+ions.

关键词： Fluorescence intensity ratio Judd-Ofelt Nd3+-doped tellurite glass Optical thermometry Rare earths