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Ultrafast laser-driven topological spin textures on a 2D magnet

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npj Computational Materials 2022年第1期8卷 1630-1635页

作者： Mara Strungaru Mathias Augustin elton J.g.Santos Institute for Condensed Matter Physics and Complex Systems School of Physics and AstronomyThe University of EdinburghEdinburghEH93FDUK Donostia International Physics Center(DIPC) 20018Donostia-San SebastiánBasque CountrySpain Higgs Centre for Theoretical Physics The University of EdinburghEdinburghEH93FDUK

Ultrafast laser excitations provide an efficient and low-power consumption alternative since different magnetic properties and topological spin states can be triggered and manipulated at the femtosecond(fs)***,it is largely unknown whether laser excitations already used in data information platforms can manipulate the magnetic properties of recently discovered two-dimensional(2D)van der Waals(vdW)*** we show that ultrashort laser pulses(30−85 fs)can not only manipulate magnetic domains of 2D-XY CrCl_(3)ferromagnets,but also induce the formation and control of topological nontrivial meron and antimeron spin *** observed that these spin quasiparticles are created within~100 ps after the excitation displaying rich dynamics through motion,collision and annihilation with emission of spin waves throughout the *** findings highlight substantial opportunities of using photonic driving forces for the exploration of spin textures on 2D magnetic materials towards magneto-optical topological applications.

关键词： laser excitation topological

Seroprevalence of SARS-COV-2 Exposure among “High-Risk” Populations (Healthcare Workers, People Who Attend Markets, and School Children) in Zanzibar

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Advances in Infectious Diseases 2024年第1期14卷 34-55页

作者： Ame Masemo Solomon Mwakasungula Khamis Kheir Erick Mgina Nahya Khamis Irabi Kassim Bihila Bakar Khamis Salim Sarah Mswata Kibwana Omar Theckla Kazimoto Linzy elton Honorati Masanja Mayassa Ally Zanzibar Health Research Institute Binguni Zanzibar Ifakara Health Institute Bagamoyo Tanzania National Institute for Medical Research Muhimbili Centre Dar es Salaam Tanzania Binguni Public Health Laboratory Binguni Zanzibar Department of Microbiology Mnazi Mmoja Hospital Stone Town Zanzibar Centre for Clinical Microbiology Royal Free Hospital Campus University College London London UK

In Zanzibar, from the start of the pandemic in March 2020 to the time of sampling in December 2020, SARS-CoV-2 seroprevalence data was limited. We conducted a seroprevalence study to evaluate the magnitude of SARS-CoV-2 exposure among healthcare workers, school children, and people who attended general markets in Zanzibar. The objectives of the study were to analyse the total antibodies from selected higher-risk population groups in order to determine magnitude in SARS CoV-2 exposure. Blood samples were collected from eligible and consented participants (adults and children), and their serum was analyzed for total antibodies against SARS-CoV-2 using ELISA. A questionnaire was used to collect participants’ demographic and clinical data. The overall SARS-CoV-2 seroprevalence across all age groups was 33%, and a higher seroprevalence was observed in the 40 - 49 years’ age group relative to other ages as well as in those who attended markets. A runny nose (18.8% of participants) was the most frequently reported SARS-CoV-2 infection-related symptom. Multivariable analysis showed significantly higher odds of infection in people living in urban districts. The findings provide insight into SARS-CoV-2 infection among school children, health workers, and people who attended markets in Zanzibar in the early stages of the pandemic. Exposure in these groups might have been influenced by infection and prevention strategies taken by the government, as well as shopping behavior, school overcrowding, and population density in urban settings. The study had methodological limitations, including cross-sectional design. Further, well-designed, longitudinal studies are recommended to understand exposure and transmission at a population level.

关键词： SARS-CoV-2 Seroprevalence Zanzibar ELISA COVID-19

Reflecting Brownian Motion and the gauss–Bonnet–Chern Theorem

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Communications in Mathematics and Statistics 2023年第3期11卷 609-627页

作者： Weitao Du elton P.Hsu School of Mathematics University of Science and Technology of ChinaHefeiAnhui ProvincePeople’s Republic of China Department of Mathematics Northwestern UniversityEvanstonIL60208USA

We use reflecting Brownian motion(RBM)to prove the well-known gauss–Bonnet–Chern theorem for a compact Riemannian manifold with *** boundary integrand is obtained by carefully analyzing the asymptotic behavior of th... 详细信息

关键词： Manifold with boundary gauss-Bonnet-Chern theorem Reflecting Brownian motion

Relativistic domain-wall dynamics in van der Waals antiferromagnet MnPS_(3)

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npj Computational Materials 2022年第1期8卷 27-35页

作者： Ignacio M.Alliati Richard F.L.Evans Kostya S.Novoselov elton J.g.Santos School of Mathematics and Physics Queen’s University BelfastBelfastBT71NNUK Department of Physics The University of YorkYorkYO105DDUK Institute for Functional Intelligent Materials National University of SingaporeSingapore117544Singapore Institute for Condensed Matter Physics and Complex Systems School of Physics and AstronomyThe University of EdinburghEdinburghEH93FDUK Higgs Centre for Theoretical Physics The University of EdinburghEdinburghEH93FDUK

The discovery of two-dimensional(2D)magnetic van der Waals(vdW)materials has flourished an endeavor for fundamental problems as well as potential applications in computing,sensing and storage *** particular interest are antiferromagnets,which due to their intrinsic exchange coupling show several advantages in relation to ferromagnets such as robustness against external magnetic *** we show that,despite of this cornerstone,the magnetic domains of recently discovered 2D vdW MnPS_(3)antiferromagnet can be controlled via magnetic fields and electric *** achieve ultrafast domain-wall dynamics with velocities up to~3000 m s^(−1)within a relativistic *** contraction and emission of spin-waves in the terahertz gap are observed with dependence on the edge termination of the *** results indicate that the implementation of 2D antiferromagnets in real applications can be further controlled through edge engineering which sets functional characteristics for ultrathin device platforms with relativistic features.

关键词： relativistic dynamics antiferromagnet

Attention-based LSTM predictive model for the attitude and position of shield machine in tunneling

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Underground Space 2023年第6期13卷 335-350页

作者： Qing Kang elton J.Chen Zhong-Chao Li Han-Bin Luo Yong Liu State Key Laboratory of Water Resources Engineering and Management Wuhan UniversityWuhan 430072China School of Civil&Hydraulic Engineering Huazhong University of Science&TechnologyWuhan 430074China Tunnel Engineering Company Wuhan Municipal Construction Group Co.LtdWuhan 430023China

Shield machine may deviate from its design axis during excavation due to the uncertainty of geological environment and the complexity of *** study therefore introduced a framework to predict the attitude and position of shield machine by combining long short-term memory(LSTM)model with attention *** data obtained from the Wuhan Rail Transit Line 6 project were utilized to verify the feasibility of the proposed *** adding the attention mechanism into the LSTM model,the proposed model can focus more on parameters with higher *** analysis based on Pearson correlation coefficient was conducted to improve the prediction efficiency and reduce the irrelevant input *** with LSTM model,LSTM-attention model has higher *** mean value of coefficient of determination(R^(2))increases from 0.625 to 0.736,and the mean value of root mean square error(RMSE)decreases from 3.31 to *** proposed LSTM-attention model can provide an effective prediction for attitude and position of shield machine in practical tunneling engineering.

关键词： LSTM Shield machine Attitude and position prediction Attention mechanism Tunnel excavation

Synchronous shield tunnelling technology combining advancement and segment fabrication:Principle,verification and application

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Underground Space 2023年第6期13卷 23-47页

作者： Yeting Zhu Yanfei Zhu elton J.Chen Yixin Zhai Rui Min Bin Tang Xin Huang Shanghai Tunnel Engineering Co.Ltd. Shanghai 200232China School of Civil&Hydraulic Engineering Huazhong University of Science&TechnologyWuhanHubei 430074China National Innovation Center for Digital Construction WuhanHubei 430074China Department of geotechnical Engineering College of Civil EngineeringTongji UniversityShanghai 200092China

Through the active control of shield thrust system oil pressures,a synchronous shield tunnelling technology combining advancement and segment fabrication was *** key to this technology was to completely exploit the additional stroke of the hydraulic jacks generated by the axial insertion of a key block to assemble the *** the tunnelling project of the Shanghai Airport Railway Link Line as a demonstration project,this paper uses a large model test platform for this synchronous technology.A single-ring construction process along a straight line was simulated,in which the theoretical external loads were implemented on the shield *** feasibility and reliability of this synchronous technology were evaluated considering the accuracy of total thrust force control,maintenance of tunnelling speed and shield postures and segment *** effectiveness of the redistribution principle for the missing thrust force due to the withdrawal of cylinders located in the segment fabrication region was ***,some other interesting phenomena were observed in the practical application in addition to the model *** technology primarily realizes synchronous assembly by improving the control of the propulsion system of conventional shield machines without any transformation of the shield machine’s primary structure,segment patterns or excavation *** proposed method has good adaptability and a low construction cost,which will be beneficial for future long-distance tunnelling projects.

关键词： Shield tunnel Shield machine Model test Shield tunnelling Synchronous assembly

Non-invasive tests for the prediction of post-hepatectomy liver failure in the elderly

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Hepatoma Research 2020年第6期6卷 41-57页

作者： giovanni Marasco Antonio Colecchia Matteo Milandri Benedetta rossini Luigina Vanessa Alemanni elton Dajti Federico Ravaioli Matteo Renzulli Rita golfieri Davide Festi Department of Medical and Surgical Sciences(DIMEC) University of BolognaBologna 40138Italy Unit of gastroenterology Borgo Trento University Hospital of VeronaP.le Aristide Stefani 1Verona 37126Italy Radiology Unit Sant’Orsola Malpighi HospitalBologna 40138Italy

Post-hepatectomy liver failure(PHLF)is associated with great morbidity and mortality after resection of hepatocellular *** studies have underlined that advanced age could be a potential factor influencing post-operative complications and long-term *** the past,candidates for resection were based on the Child-Pugh classification,the predictive value of which was rather *** selection of patients undergoing resection in Western countries is based on the assessment of portal hypertension(PH),which is clinically assessed by measurement of the hepatic venous pressure gradient,an invasive and costly ***,there have been several attempts to identify the best non-invasive test(NIT)to accurately predict *** biochemical NITs for the prediction of PHLF are focused on evaluation of underlying liver cirrhosis and *** them,FIB-4,which also includes the patient's age,seems to have more robust supporting *** Europe and the USA.,the most tested and reliable NIT for predicting PHLF is the evaluation of liver stiffness measurement,which is also influenced by *** parameters are promising tools which are used only in specialized centers however,and when *** volume parameters,as well as contrast-enhanced data,demonstrate good accuracy in predicting *** this scenario,the evaluation of sarcopenia and bone mineral density through contextual imaging allows the delineation of PHLF in at-risk elderly *** studies focused on parameters for the evaluation of PHLF in elderly patients are needed.

关键词： Post-hepatectomy liver failure liver resection elderly liver stiffness measurement indocyanine green retention test

Some Concerns Related to the Idea of Energetic Complementarity and Its Application

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Energy and Power Engineering 2017年第9期9卷 482-485页

作者： Flávio P. Livi elton g. rossini Alexandre Beluco Instituto Mensura Universidade Federal do Rio Grande do Sul Porto Alegre Brazil Universidade Estadual do Rio grande do Sul Porto Alegre Brazil Universidade Federal do Rio grande do Sul Porto Alegre Brazil

This letter to the editor presents some notes on energetic complementarity and a growing understanding of its role as a planning tool. This letter looks at the fact that an increasing number of works in recent years on this subject has promoted an increase in its level of importance in the design and operation of energy systems. The main change is the consideration of complementarity no longer as a consequence but as a design parameter. The continental dimension of Brazil, for example, should make it obvious that complementarities should be sought among the various energy resources available.

关键词： Component: Energetic Complementarity Complementary Energy Re-sources

Predictive factors for hepatocellular carcinoma recurrence after curative treatments

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Hepatoma Research 2020年第6期6卷 58-76页

作者： giovanni Marasco Federico Ravaioli Amanda Vestito Benedetta rossini elton Dajti LuigiColecchia Kamela gjini Matteo Renzulli Rita golfieri Davide Festi Antonio Colecchia Department of Medical and Surgical Sciences(DIMEC) University of BolognaBologna 40138Italy Radiology Unit Sant’Orsola Malpighi HospitalBologna 40138Italy Unit of gastroenterology Borgo Trento University Hospital of VeronaVerona 37126Italy

Hepatocellular carcinoma(HCC)is the fifth most common neoplasm *** of HCC after resection or loco-regional therapies represents an important clinical issue as it affects up to 70%of *** can be divided into early or late,if it occurs within or after 24 months after treatment,*** the predictive factors for early recurrence are mainly related to tumour biology(local invasion and intrahepatic metastases),late recurrences are mainly related to de novo tumour ***,it is important to recognize these factors prior to any treatment in each patient,in order to optimize the treatment strategy and follow-up after *** aim of this review is to summarize the current evidence available regarding predictive factors for the recurrence of HCC,according to the different therapeutic strategies *** particular,we will discuss the role of new ultrasound-based techniques and biological features,such as tumor-related and circulating biomarkers,in predicting HCC *** advances in imaging-related parameters in computed-tomography scans and magnetic resonance imaging will also be discussed.

关键词： Liver resection trans-arterial chemoembolization radiofrequency ablation liver stiffness measurement indocyanine green retention test