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Revisiting non-linear Thomson scattering with metamaterials

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National Science Review 2024年第1期11卷 71-72页

作者： natalia M.Litchinitser Department of Electrical and Computer Engineering Duke University

Non-linear optics is a branch of optics that studies the intriguing and sometimes unexpected ways in which light and matter interact at high intensities, when the polarization density does not respond linearly to the electric field of the light. The pursuit of the perfect non-linear optical material has been ongoing ever since the pioneering experiment on second harmonic generation carried out by Franken in 1961 [1]. Indeed,

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Double-check in Lizard Age Estimation:Use of Phalanx Bone and Keratin Claw Sheath Lamellas

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Asian Herpetological Research 2024年第1期15卷 59-61页

作者： Eduard GALOYAN natalia SOPILKO Anna KOVALYEVA Anna CHAMKINA A.N.Severtsov Institute of Ecology and Evolution Moscow 119071Russia Lomonosov Moscow State University Leninskie Gori 1Moscow 119991Russia

Dear Editor,The problem of age estimation in amphibians and reptiles with annual fluctuations of growth pattern has been considered to be mostly solved since the skeletochronological method was introduced(Kleinenberg and Smirina,1969).This method is based on counting the number of lines of arrested growth(LAGs)—cyclical growth marks that are usually formed annually and characterized by different optical aspects within the tubular bones.

关键词： estimation method usual

On the two-layer high-level Green-Naghdi model in a general form

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Journal of Hydrodynamics 2024年第1期36卷 78-86页

作者： Bin-bin Zhao Tian-yu Zhang Zhan Wang Wen-yang Duan Alexander Chesnokov natalia Shmakova College of Shipbuilding Engineering Harbin Engineering UniversityHarbin150001China Qingdao Innovation and Development Center of Harbin Engineering University Qingdao266000China Lavrentyev Institute of Hydrodynamics NovosibirskRussia

The traditional high-level Green-Naghdi(HLGN)model,which uses the polynomial as the shape function to approximate the variation of the horizontal-and vertical-velocity components along the vertical direction for each-fluid layer,can accurately describe the large-amplitude internal waves in a two-layer system for the shallow configuration(h_(2)/λ■1,h_(1)/λ■1).However,for the cases of the deep configuration(h_(2)/λ■1,h_(1)/λ=O(1)),higher-order polynomial is needed to approximate the variation of the velocity components along the vertical direction for the lower-fluid ***,however,introduces additional unknowns,leading to a significant increase in computational *** paper,for the first time,derives a general form of the HLGN model for a two-layer fluid system,where the general form of the shape function is used during the *** obtaining the general form of the two-layer HLGN equations,corresponding solutions can be obtained by determining the reasonable shape ***-amplitude internal solitary waves in a deep configuration are studied by use of two different HLGN *** of the two HLGN models shows that the polynomial as the shape function for the upper-fluid layer and the production of exponential and polynomial as the shape function for the lower-fluid layer is a good *** comparing with Euler’s solutions and the laboratory measurements,the accuracy of the two-layer HLGN model is verified.

关键词： High-level Green-Naghdi(HLGN)model general form internal waves deep configuration

Terrorism Attack Classification Using Machine Learning: The Effectiveness of Using Textual Features Extracted from GTD Dataset

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Computer Modeling in Engineering & Sciences 2024年第2期138卷 1427-1467页

作者： Mohammed Abdalsalam Chunlin Li Abdelghani Dahou natalia Kryvinska School of Computer Science and Technology Wuhan University of TechnologyWuhan430070China LDDI Laboratory Faculty of Science and TechnologyUniversity of Ahmed DRAIAAdrar01000Algeria Information Systems Department Faculty of ManagementComenius UniversityBratislava82005Slovakia

One of the biggest dangers to society today is terrorism, where attacks have become one of the most significantrisks to international peace and national security. Big data, information analysis, and artificial intelligence (AI) havebecome the basis for making strategic decisions in many sensitive areas, such as fraud detection, risk management,medical diagnosis, and counter-terrorism. However, there is still a need to assess how terrorist attacks are related,initiated, and detected. For this purpose, we propose a novel framework for classifying and predicting terroristattacks. The proposed framework posits that neglected text attributes included in the Global Terrorism Database(GTD) can influence the accuracy of the model’s classification of terrorist attacks, where each part of the datacan provide vital information to enrich the ability of classifier learning. Each data point in a multiclass taxonomyhas one or more tags attached to it, referred as “related tags.” We applied machine learning classifiers to classifyterrorist attack incidents obtained from the GTD. A transformer-based technique called DistilBERT extracts andlearns contextual features from text attributes to acquiremore information from text data. The extracted contextualfeatures are combined with the “key features” of the dataset and used to perform the final classification. Thestudy explored different experimental setups with various classifiers to evaluate the model’s performance. Theexperimental results show that the proposed framework outperforms the latest techniques for classifying terroristattacks with an accuracy of 98.7% using a combined feature set and extreme gradient boosting classifier.

关键词： Artificial intelligence machine learning natural language processing data analytic DistilBERT feature extraction terrorism classification GTD dataset

Numerical Analysis of Permeability of Functionally Graded Scaffolds

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Fluid Dynamics & Materials Processing 2024年第7期20卷 1463-1479页

作者： Dmitry Bratsun natalia Elenskaya Ramil Siraev Mikhail Tashkinov Laboratory of Mechanics of Biocompatible Materials and Devices Perm National Research Polytechnic UniversityPerm614990Russia

In this work,we numerically study the hydrodynamic permeability of new-generation artificial porous materials used as scaffolds for cell growth in a perfusion *** consider two popular solid matrix designs based on triply periodic minimal surfaces,the Schwarz P(primitive)and D(diamond)surfaces,which enable the creation of materials with controlled porosity *** latter property is crucial for regulating the shear stress field in the pores of the scaffold,which makes it possible to control the intensity of cell *** permeability of functionally graded materials is studied within the framework of both a microscopic approach based on the Navier-Stokes equation and an averaged description of the liquid filtration through a porous medium based on the equations of the Darcy or Forchheimer *** calculate the permeability coefficients for both types of solid matrices formed by Schwarz surfaces,study their properties concerning forward and reverse fluid flows,and determine the ranges of Reynolds number for which the description within the Darcy or Forchheimer model is ***,we obtain a shear stress field that varies along the sample,demonstrating the ability to tune spatially the rate of tissue growth.

关键词： Porous media ﬁltration models scaffolds functionally graded materials

Origin of iron-rich minerals,ooids and pisoids in the Jurassic ooidal ironstones of the Labino-Malkin region(Caucasus)

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Journal of Palaeogeography 2024年第3期13卷 475-494页

作者： natalia A.Kalinina Maxim A.Rudmin Mikhail Sherstyukov Prokopiy Maximov Abdul-Gapur Kerimov Division for Geology School of Earth Sciences&EngineeringTomsk Polytechnic University634050TomskRussia Laboratory of Sedimentology and Paleobiosphere Evolution University of Tyumen625003 TyumenRussia Institute of Earth Science North-Caucasus Federal University355009StavropolRussia

This study investigates the Middle Jurassic rocks of the Labino-Malkin zone(Caucasus),represented by ooidal ironstones,biogenic limestones,and nodular *** rocks contain ooids/*** on the mineral composition,nine types of ooids and three possible scenarios for their formation have been *** mineral composition of ooids indicates the variable conditions of their deposition and repeated changes in physical and chemical conditions of the environment,including fluctuations in theredox *** access of oxygen in the bottom environment as a factor of increasing oxic conditions was associated with the regression of the sea and/or the inflow of meteoric *** main sources of ooids are the drift of material from the continent and convecting metal-bearing meteoric and/or deep solutions.

关键词： Ooidal ironstones Mineral formation Ooids Pisoids Mineral chemistry

Early Neoproterozoic Granite-Gneisses of the Junggar Alataw(Southeastern Kazakhstan):Age,Petrogenesis and Tectonic Implications

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Acta Geologica Sinica(English Edition) 2024年第1期98卷 67-82页

作者： Nadezhda KANYGINA Andrey TRETYAKOV Dmitriy ALEXEIEV Kirill DEGTYAREV Anfisa SKOBLENKO natalia SOLOSHENKO Boris ERMOLAEV Geological Institute Russian Academy of SciencesMoscow 119017Russia A.N.Zavaritsky Institute of Geology and Geochemistry Ural Branch of the Russian Academy of SciencesYekaterinburg 620016Russia

The combined petrographic,petrological,geochemical and geochronological study of the Neoproterozoic gneisses of the Sarychabyn and Baskan complexes of the Junggar Alataw of South Kazakhstan elucidate the Precambrian tectonic evolution of the Aktau–Yili *** is one of the largest Precambrian crustal blocks in the western Central Asian orogenic *** U-Pb single-grain zircon ages indicate that granite-gneisses formed from the same source and crystallised in the early Neoproterozoic ca.930–920 *** chemical composition of gneisses corresponds to A2-type *** whole-rock Nd isotopic characteristics(εNd(t)=−4.9 to−1.0 and TNd(DM-2st)=1.9 to 1.7 Ga)indicate the involvement of Paleoproterozoic crustal rocks in magma *** Neoproterozoic ca.930–920 Ma A-type granitoids in the Aktau–Yili terrane of South and Central Kazakhstan might reflect within-plate magmatism adjacent to the collisional belt or a local extension setting in back-arc areas of the continental arc.

关键词： granitoid magmatism geochemistry geochronology Sm-Nd isotope systematics Neoproterozoic Junggar Alataw Kazakhstan Central Asian orogenic belt

Effect of low concentration electrolytes on the formation and corrosion resistance of PEO coatings on AM50 magnesium alloy

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Journal of Magnesium and Alloys 2024年第4期12卷 1386-1405页

作者： Peng Xie Carsten Blawert Maria Serdechnova natalia Konchakova Tatsiana Shulha Ting Wu Mikhail L.Zheludkevich Institute of Surface Science Helmholtz-Zentrum HereonMax-Planck Strasse 121502 GeesthachtGermany Institute for Materials Science Faculty of EngineeringKiel UniversityKaiserstrasse 224143 KielGermany

In this paper,the formation process,morphology,and electrochemical performance of PEO coatings on AM50 magnesium alloy prepared in low concentration phosphate,aluminate,and phosphate-aluminate electrolytes were systematically *** results show that the coatings prepared from the phosphate electrolytes have a higher thickness and better corrosion resistance properties compared to the other *** coatings prepared from low concentration phosphate-aluminate mixed electrolytes have slightly thinner thickness,a similar coating structure and an order of magnitude lower value of electrochemical impedance compared with phosphate electrolyte *** Coatings prepared from low concentration aluminate electrolytes have the lowest thickness and the worst corrosion resistance properties which gets close to corrosion behavior of the bare AM50 under the same test *** application,coatings prepared from single low concentration phosphate electrolytes and low concentration phosphate-aluminate electrolytes have greater potential than single low concentration aluminate ***,reducing the electrolyte concentrations of coating forming ions too much has negative influence on the coating growth rate.

关键词： Plasma electrolytic oxidation Low concentration electrolytes Corrosion resistance AM50 magnesium alloy

Protein-nucleic acid hybrid nanostructures for molecular diagnostic applications

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Nano Research 2024年第10期17卷 9003-9014页

作者： Noah R.Sundah Yuxuan Seah Auginia natalia Xiaoyan Chen Panida Cen Yu Liu Huilin Shao Institute for Health Innovation and Technology National University of SingaporeSingapore 117599Singapore Department of Biomedical Engineering College of Design and EngineeringNational University of SingaporeSingapore 117583Singapore Integrative Sciences and Engineering Programme NUS Graduate SchoolNational University of SingaporeSingapore 119077Singapore Institute of Molecular and Cell Biology Agency for ScienceTechnology and ResearchSingapore 138673Singapore Department of Surgery Yong Loo Lin School of MedicineNational University of SingaporeSingapore 117597Singapore

Molecular diagnostic technologies empower new clinical opportunities in precision ***,existing approaches face limitations with respect to performance,operation and *** molecules including proteins and nucleic acids are being increasingly adopted as tools in the development of new molecular diagnostic *** particular,leveraging their complementary properties—the functional diversity of proteins and the precision programmability of nucleic acids—a wide range of protein–nucleic acid hybrid nanostructures have been *** hybrid structures take diverse forms,ranging from one-dimensional to three-dimensional hybrids,as static assemblies to dynamic machines,and possess myriad functions to recognize target biomarkers,encode vast information and execute catalytic *** by recent advances in this area of molecular nanotechnology,we review the state-of-art design and application of various types of protein–nucleic acid hybrid nanostructures for molecular diagnostics,and present an outlook on the challenges and opportunities for emerging pre-clinical and clinical applications,highlighting the promise for earlier detection,more refined diagnosis and highly tailored treatment decision that ultimately lead to improved patient outcomes.

关键词： molecular nanotechnology DNA-protein hybrid molecular diagnostics precision medicine