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A GPU-Accelerated Mixed-Precision WeNO Method for extremal Black Hole and Gravitational Wave Physics Computations

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Communications on Applied Mathematics and Computation 2023年第1期5卷 97-115页

作者： s.ott e.field sigal Gottlieb Zachary J.Grant Leah F.Isherwood Gaurav Khanna University of Massachusetts Dartmouth North DartmouthMA 02747USA Department of Computational and Applied Mathematics Oak Ridge National LaboratoryOak RidgeTN 37830USA University of Rhode Island KingstonRI 02881USA

We develop and use a novel mixed-precision weighted essentially non-oscillatory(WeNO)method for solving the Teukolsky equation,which arises when modeling perturbations of Kerr black *** show that WeNO methods outperform higher-order finite-difference methods,standard in the discretization of the Teukolsky equation,due to the need to add dissipation for stability purposes in the *** particular,as the WeNO scheme uses no additional dissipation,it is well suited for scenarios requiring long-time evolution such as the study of price tails and gravitational wave emission from extreme mass ratio *** the mixed-precision approach,the expensive computation of the WeNO weights is performed in reduced floating-point precision that results in a significant speedup factor of≈*** addition,we use state-of-the-art Nvidia general-purpose graphics processing units and cluster parallelism to further accelerate the WeNO *** optimized WeNO solver can be used to quickly generate accurate results of significance in the.field of black hole and gravitational wave *** apply our solver to study the behavior of the Aretakis charge—a conserved quantity,that if detected by a gravitational wave observatory like LIGO/Virgo would prove the existence of extremal black holes.

关键词： Numerical methods-Finite differencing Hyperbolic Partial differential equations Black holesblack holes WeNO

An efficient Long short-TermMemory and Gated Recurrent Unit Based smart Vessel Trajectory Prediction Using Automatic Identification system Data

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Computers, Materials and Continua 2024年第1期81卷 1789-1808页

作者： Zaman U. Khan J. Lee e. Hussain s. Balobaid A.s. Aburasain R.Y. Kim K. Department of Computer engineering Chungnam National University Daejeon 34134 South Korea Department of environmental IT engineering Chungnam National University Daejeon 34134 South Korea Autonomous ship Research Center Samsung Heavy Industries Daejeon 34051 South Korea ICAROs Center (PRIsMA Lab) University of Naples Federico II Naples 80131 Italy Department of Computer science College of Computer Science and Information Technology Jazan University Jazan 45142 Saudi Arabia

Maritime transportation, a cornerstone of global trade, faces increasing safety challenges due to growing sea traffic volumes. This study proposes a novel approach to vessel trajectory prediction utilizing Automatic Identification system (AIs) data and advanced deep learning models, including Long short-Term Memory (LsTM), Gated Recurrent Unit (GRU), Bidirectional LsTM (DBLsTM), simple Recurrent Neural Network (simpleRNN), and Kalman Filtering. The research implemented rigorous AIs data preprocessing, encompassing record deduplication, noise elimination, stationary simplification, and removal of insignificant trajectories. Models were trained using key navigational parameters: latitude, longitude, speed, and heading. spatiotemporal aware processing through trajectory segmentation and topological data analysis (TDA)was employed to capture dynamic *** using a three-month AIs dataset demonstrated significant improvements in prediction accuracy. The GRU model exhibited superior performance, achieving training losses of 0.0020 (Mean squared error, Mse) and 0.0334 (Mean Absolute error, MAe), with validation losses of 0.0708 (Mse) and 0.1720 (MAe). The LsTM model showed comparable efficacy, with training losses of 0.0011 (Mse) and 0.0258 (MAe), and validation losses of 0.2290 (Mse) and 0.2652 (MAe). Both models demonstrated reductions in training and validation losses, measured by MAe, Mse, Average Displacement error (ADe), and Final Displacement error (FDe). This research underscores the potential of advanced deep learning models in enhancing maritime safety through more accurate trajectory predictions, contributing significantly to the development of robust, intelligent navigation systems for the maritime industry. © 2024 The Authors. Published by Tech science Press.

关键词： AIs data deep learning GRU LsTM smart vessel Trajectory prediction

Multitarget Thiol-Activated Tetrapyridyl Gold(Ⅲ)Complexes for Hypoxic Cancer Therapy

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CCs Chemistry 2024年第3期6卷 783-797页

作者： Xue-Quan Zhou selda Abyar Imma Carbo-Bague Lan Wang sebastian Türck Maxime Asiegler Uttara Basu Ingo ott Rongfang Liu Adriaan PIJzerman sylvestre Bonnet Institute of Biopharmaceutical and Health engineering Tsinghua Shenzhen International Graduate School(SIGS)Tsinghua UniversityShenzhen 518055 Leiden Institute of Chemistry Leiden University2333 CC Leiden Department of Chemistry Simon Fraser UniversityBurnabyBritish Columbia V5A 1S6 Institute of Medicinal and Pharmaceutical Chemistry Technische Universität Braunschweig38106 Braunschweig Department of Chemistry Johns Hopkins UniversityBaltimoreMaryland 21218 Division of Drug Discovery&safety Leiden Academic Centre for Drug ResearchLeiden University2333 CC Leiden

Gold complexes have emerged as promising anticancer metallodrugs due to their efficient thioredoxin reductase(TrxR)inhibition,which disturbs the redox balance of cancer ***,in this model,the role of the ligand(s)coordinated to gold is often *** this work,we present a series of tetrapyridyl Au(Ⅲ)complexes that exhibit thiol-induced release of a Au(Ⅰ)ion and a tetrapyridyl *** formation of a free Au(Ⅰ)center is responsible for the expected TrxR ***,the released ligand,which was visible in cells due to its intense blue fluorescence,showed excellent binding properties to the heRG potassium ***,these ligands ended up in the lysosomes,resulting in significant lysosome ***,the Au(Ⅲ)complexes presented in this work showed broad-spectrum anticancer properties,both in hypoxic 2D monolayers and 3D tumor *** suggest that the interaction of the released Au(Ⅰ)center and the tetrapyridyl ligand with two different protein targets may combine into prodrugs that overcome hypoxia-induced drug deactivation.

关键词： anticancer Au(Ⅲ)complexes enzyme inhibtion potassium channel affinity lysosome damage cell imaging prodrug

Avian responses to an extreme weather event:The case of the‘Filomena’snowstorm in Madrid(central spain)

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Avian Research 2024年第2期15卷 180-186页

作者： Carlos Lazaro Carlos sanchez-García Fabian Casas e.Jorge Tizado Department of Research Fundacion Artemisan13001 Ciudad RealSpain Department of Zoology Faculty of SciencesUniversity of GranadaGranadaSpain Department of Biodiversity and environmental Management Universidad de Leon24401 PonferradaSpain

Cold spells and severe weather may have detrimental effects in wild birds,but owing to the stochastic nature of these events,it is not always possible to measure their *** January 2021,a strong snowstorm known as‘Filomena’affected spain,mainly the region of Madrid(Central spain),which was fully covered with snow and suffered freezing temperatures for a *** bird surveys conducted in the winter-spring of 2020 and 2021(before and after Filomena)at same locations,we addressed the possible impact of the cold spell in three widespread gamebirds:Wood Pigeon(Columba palumbus),eurasian Magpie(Pica pica)and Red-legged Partridge(Alectoris rufa).No significant abundance differences were found between years for none of the species and hunting pressure was only significantly reduced for Partridges,hence this species may have been negatively affected by *** suggest that in response to Filomena,Pigeons conducted partial migration in search of better conditions,while Magpies aggregated in certain areas of Madrid and Partridges endured the harsh conditions within their home *** results highlight the importance to alleviate negative impacts of extreme weather events in wild birds through management actions,especially for sedentary species.

关键词： Alectoris rufa Climate change Cold spell Columba palumbus Migration Pica pica Winter

Governance in the exploration of global and regional determinants of ICT development

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International Journal of Innovation studies 2024年第2期8卷 132-153页

作者： Charles s.saba simplice A.Asongu Nicholas Ngepah Yolande e.Ngoungou school of economics College of Business and EconomicsUniversity of JohannesburgJohannesburgSouth Africa Department of econornic&Data science New Uzbekistan University54 Mustaili AvenueTashkent100007Uzbekistan University of Yaounde 2 SoaCameroon

The present study assesses how governance affects information and communication technology(IcT)at the global level contingent on macroeconomic policy factors such as trade,foreign direct investment(FDI),manufacturing value added,and agricultural value *** study focuses on 183 countries from 2003 to 2021,and the empirical evidence is based on the generalized method of moments(GMM).The following main findings are *** the full sample,governance unconditionally promotes ICT development,while trade openness(industrial added value)moderates governance to promote(dampen)ICT *** sub-saharan Africa,only trade openness effectively moderates governance to induce an overall positive effect on ICT,while in the Middle east and North Africa(MeNA)region,all policy variables moderate governance for an overall positive incidence on ICT sector *** findings for the MeNA region are confirmed in the europe and Central Asia(eCA)region,with the exception of the moderating role of industrial added value,which engenders an overall negative *** the east and south Asia and the Pacific(esAP)countries,one overall positive incidence is apparent in the role of trade openness,while net negative effects are established from the moderating roles of industrial added value and agricultural added *** the American sub-sample,a positive(negative)net effect is apparent from the role of industrial added value(trade)in moderating the incidence of gover-nance on ICT sector ***,policy implications are discussed.

关键词： ICT Governance Trade FDI Industry Agriculture

Unravelling COVID-19 waves in Rio de Janeiro city:Qualitative insights from nonlinear dynamic analysis

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Infectious Disease Modelling 2024年第2期9卷 314-328页

作者： Adriane s.Reis Laurita dos santos Américo Cunha Jr Thaís C.R.O.Konstantyner elbert e.N.Macao Institute of science and Technology Federal University of São PauloSão Josédos CamposSPBrazil Physics Institute University of São PauloSão PauloSPBrazil scientific and Technological Institute Universidade BrasilSão PauloSPBrazil Department of Applied Mathematics Rio de Janeiro State UniversityRio de JaneiroRJBrazil Paulista school of Medicine Federal University of São PauloSão PauloSPBrazil

since the COVID-19 pandemic was first reported in 2019,it has rapidly spread around the *** countries implemented several measures to try to control the virus *** healthcare system and consequently the general quality of life population in the cities have all been significantly impacted by the Coronavirus *** different waves of contagious were responsible for the increase in the number of cases that,unfortunately,many times lead to *** this paper,we aim to characterize the dynamics of the six waves of cases and deaths caused by COVID-19 in Rio de Janeiro city using techniques such as the Poincaréplot,approximate entropy,second-order difference plot,and central tendency *** results reveal that by examining the structure and patterns of the time series,using a set of non-linear techniques we can gain a better understanding of the role of multiple waves of COVID-19,also,we can identify underlying dynamics of disease spreading and extract meaningful information about the dynamical behavior of epidemiological time *** findings can help to closely approximate the dynamics of virus spread and obtain a correlation between the different stages of the disease,allowing us to identify and categorize the stages due to different virus variants that are reflected in the time series.

关键词： COVID-19 Nonlinear analysis Poincaréplot Central tendency measure

CLAssIFICATIONs OF DUPIN HYPeRsURFACes IN LIe sPHeRe GeOMeTRY

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Acta Mathematica scientia 2024年第1期44卷 1-36页

作者： Thomas e.CeCIL Department of Mathematics and Computer science College of the Holy CrossWorcesterMA01610USA

This is a survey of local and global classification results concerning Dupin hypersurfaces in s^(n)(or R^(n))that have been obtained in the context of Lie sphere *** emphasis is on results that relate Dupin hypersurfaces to isoparametric hypersurfaces in *** with these classification results,many important concepts from Lie sphere geometry,such as curvature spheres,Lie curvatures,and Legendre lifts of submanifolds of s^(n)(or R^(n)),are described in *** paper also contains several important constructions of Dupin hypersurfaces with certain special properties.

关键词： Dupin hypersurfaces isoparametric hypersurfaces Lie sphere geometry Lie sphere transformations Lie curvatures

enhancing high-temperature oxidation resistance(at 1000 °C) of nickel superalloy obtained by laser powder bed fusion via reactive electric spark treatment

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Transactions of Nonferrous Metals society of China 2024年

作者： s.K.MUKANOV M.I.PeTRZHIK A.e.KUDRYAsHOV e.A.NAUMOVA F.A.BAsKOV P.A.LOGINOV e.A.LeVAsHOV National University of science and Technology MIsIs

The high-temperature oxidation resistance of the nickel superalloy grown by the Laser Powder Bed Fusion (LPBF) has been significantly increased as a result of in-situ formation of a thermal barrier layer (α-Al2O3+ CaMoO4) during oxidative annealing of surface layers modified by electric spark treatment (esT). The reactive esT of the LPBF-built items based on nickel eP741NP alloy was carried out with low-melting Al-12%si， Al-6%Ca-0.6%si and Al-7%Ca-1%Mn electrodes. It was found that at esT done by Al-7%Ca-1%Mn electrode an intermetallic (β-NiAl + γ’-Ni3Al) 15 microns thick layer reinforced by spherical oxide (CaMe)O nanoparticles was formed. Formation of that structure increases the wear resistance of LPBF nickel superalloy by 4.5 times. Further oxidative annealing at 1000 °C lead to a formation of continuous two-layered coating with an inner layer of α-Al2O3and an outer layer of CaMoO4， which together act as an effective barrier preventing the diffusion of oxygen into the volume of the superalloy.

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Mast cell activation syndrome:An up-to-date review of literature

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World Journal of Clinical Pediatrics 2024年第2期13卷 104-113页

作者： ÖnerÖzdemir Gökçe Kasımoğlu Ayşegül Bak Hüseyin sütlüoğlu süreyya savaşan Department of Pediatric Allergy and Immunology Sakarya UniversitySakaryaAdapazarı54100Türkiye Department of Pediatrics Sakarya UniversitySakaryaAdapazarı54100Türkiye Department of Pediatrics Kocaeli City HospitalKocaeli 50123Türkiye Department of Pediatrics Children’s Hospital of MichiganHematology/OncologyCentral Michigan University College of MedicineMount PleasantMI 48859United States Barbara Ann Karmanos Cancer Institute Wayne State UniversityDetroitMI 12345United States

Mast cells are a subtype of white blood cells and are involved in the immune *** cells contain many chemical substances called mediators,which are involved in the allergic *** fact that mast cells play a role in many events that require urgent intervention,especially anaphylaxis,has led to a more detailed study of these *** diseases also caused by dysfunctions of mast cells have been examined in many *** instance,mast cell activation syndrome is known as an augmented number of cells due to decreased cell death,resulting in clinical symptoms affecting many *** main common symptoms include flushing,hypotension,urticaria,angioedema,headache,vomiting and *** the underlying mechanism is not yet clearly known,we aim to review the literature in a broad perspective and bring together the existing knowledge in the light of the literature due to the diversity of its involvement in the body and the fact that it is a little known syndrome.

关键词： Mast cell Mast cell activation syndrome Tryptase Histamine