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Acta Geochimica 2024年第2期43卷 399-410页

作者： salih M.Awadh Zinah s.Al-Ankaz Mohanad R.A.Al-Owaidi John s.Armstrong-Altrin Department of Geology College of ScienceUniversity of BaghdadBaghdadIraq Department of Geology College of ScienceUniversity of WasitWasit 52011Iraq Department of Applied Geology College of ScienceUniversity of BabylonBabylon 51001Iraq Unidad de Procesos Oceanicos y Costeros Instituto de Ciencias del Mar y LimnologíaUniversidad Nacional Autonoma de MexicoCiudad Universitaria04510 Mexico CityCDMXMexico Department of Marine sciences Bharathidasan UniversityTiruchirapalliTamil Nadu 620024India

The sandstones of the Late miocene–Pliocene Dibdibba Formation in the Najaf–Karbala Plateau and Basra were examined to determine their source rocks and origin. The rare earth elements(REE) and trace elements(sc, Co, V, and Th) concentrations in these sandstones revealed that they likely derived from a single source. The steep light rare earth elements(LREE) and flat, heavy rare earth element(HREE) patterns, negative Eu anomaly, and high ΣREE contents in sandstones suggest its derivation from a suggests that a passive continental margin environment and originated from felsic source rocks. The average concentration of ΣREE is 93.5 ppm, which is lower than that of the average crustal compositions like Upper Continental Crust and Post Archean Australian shale. The higher proportion of LREE compared to HREE implies that these sandstones were recycled and derived from a distal source. The Th/Co, Th/sc, La/sc, La/Co, Eu/Eu*and(La/Lu)cn elemental ratios indicated that these Late Miocene–Pliocene sandstones were derived from felsic rocks located in the marginal region of the Arabian shield.

关键词： REE Dibdibba formation Clastic sediments Passive continental margin

Experimental implementation of phase triplicator gratings in a spatial light modulator

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Chinese Optics Letters 2024年第2期22卷 64-69页

作者：高尚 María del Mar sánchez-López Ignacio Moreno Instituto de Bioingeniería Universidad Miguel HernándezElche 03202Spain Departamento de Física Aplicada Universidad Miguel HernándezElche 03202Spain Departamento de Ciencia de Materiales Óptica y Tec.Electr´onicaUniversidad Miguel HernándezElche 03202Spain

In this work,we compare different methods for implementing a triplicator,a phase grating that generates three equiintense diffraction *** design with optimal efficiency features a continuous phase profile,which cannot be easily reproduced,and is typically affected by *** compare its performance with binary and sinusoidal phase *** also analyze the effect of quantizing the phase ***,a random approach is adopted to eliminate the additional harmonic *** all cases,a liquid-crystal-on-silicon spatial light modulator is employed to experimentally verify and compare the different approaches.

关键词： diffraction gratings phase modulation triplicator spatial light modulators

Potential applications of 7 Tesla magnetic resonance imaging in paediatric neuroimaging:Feasibility and challenges

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World Journal of Clinical Pediatrics 2024年第2期13卷 1-6页

作者： Arosh s Perera Molligoda Arachchige Letterio s Politi Final Year Medical student Faculty of MedicineHumanitas UniversityPieve Emanuele 20089Italy Department of Neuroradiology IRCCS Humanitas Research HospitalRozzano 20089MilanItaly Department of Biomedical sciences Humanitas UniversityPieve Emanuele 20072MilanItaly

The integration of 7 Tesla magnetic resonance imaging(7 T MRI)in adult patients has marked a revolutionary stride in *** this article we explore the feasibility of 7 T MRI in paediatric practice,emphasizing its feasibility,applications,challenges,and safety *** heightened resolution and tissue contrast of 7 T MRI offer unprecedented diagnostic accuracy,particularly in *** range from neuro-oncology to neonatal brain imaging,showcasing its efficacy in detecting subtle structural abnormalities and providing enhanced insights into neurological *** the promise,challenges such as high cost,discomfort,and safety concerns necessitate careful *** suggests that,with precautions,7 T MRI is feasible in paediatrics,yet ongoing studies and safety assessments are imperative.

关键词： 7 Tesla magnetic resonance imaging Pediatric imaging Feasibility Challenges

Improving Video Watermarking through Galois Field GF(2^(4)) Multiplication Tables with Diverse Irreducible Polynomials and Adaptive Techniques

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Computers, Materials & Continua 2024年第1期78卷 1423-1442页

作者： Yasmin Alaa Hassan Abdul Monem s.Rahma Department of Computer science College of ScienceUniversity of BaghdadBaghdadIraq Department of Computer science College of ScienceAl-Maarif University CollegeAl-AnbarIraq

Video watermarking plays a crucial role in protecting intellectual property rights and ensuring content *** study delves into the integration of Galois Field(GF)multiplication tables,especially GF(2^(4)),and their interaction with distinct irreducible *** primary aim is to enhance watermarking techniques for achieving imperceptibility,robustness,and efficient execution *** research employs scene selection and adaptive thresholding techniques to streamline the watermarking *** selection is used strategically to embed watermarks in the most vital frames of the video,while adaptive thresholding methods ensure that the watermarking process adheres to imperceptibility criteria,maintaining the video's visual ***,careful consideration is given to execution time,crucial in real-world scenarios,to balance efficiency and *** Peak signal-to-Noise Ratio(PsNR)serves as a pivotal metric to gauge the watermark's imperceptibility and video *** study explores various irreducible polynomials,navigating the trade-offs between computational efficiency and watermark *** parallel,the study pays careful attention to the execution time,a paramount consideration in real-world scenarios,to strike a balance between efficiency and *** comprehensive analysis provides valuable insights into the interplay of GF multiplication tables,diverse irreducible polynomials,scene selection,adaptive thresholding,imperceptibility,and execution *** evaluation of the proposed algorithm's robustness was conducted using PsNR and NC metrics,and it was subjected to assessment under the impact of five distinct attack *** findings contribute to the development of watermarking strategies that balance imperceptibility,robustness,and processing efficiency,enhancing the field's practicality and effectiveness.

关键词： Video watermarking galois field irreducible polynomial multiplication table scene selection adaptive thresholding

Local MFs Matrix Decomposition Algorithms for Elliptic BVPs in Annuli

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Numerical Mathematics(Theory,Methods and Applications) 2024年第1期17卷 93-120页

作者： C.s.Chen Andreas Karageorghis Min Lei school of Mathematics and Natural sciences University of Southern MississippiHattiesburgMS 39406USA Department of Mathematics and statistics University of CyprusP.O.Box 20537Nicosia 1678Cyprus College of Mathematics Taiyuan University of TechnologyTaiyuan 030024P.R.China

We apply the local method of fundamental solutions(LMFs)to boundary value problems(BVPs)for the Laplace and homogeneous biharmonic equations in *** appropriately choosing the collocation points,the LMFs discretization yields sparse block circulant system *** a result,matrix decomposition algorithms(MDAs)and fast Fourier transforms(FFTs)can be used for the solution of the systems resulting in considerable savings in both computational time and storage *** accuracy of the method and its ability to solve large scale problems are demonstrated by applying it to several numerical experiments.

关键词： Local method of fundamental solutions Poisson equation biharmonic equation matrix decomposition algorithms fast Fourier transforms

Development and testing of a high-power s-band klystron at BINP sB RAs

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Nuclear science and Techniques 2024年第7期35卷 58-67页

作者： A.Levichev A.Barnyakov s.samoylov D.Nikiforov V.Ivanov M.Arsentyeva D.Chekmenev O.Pavlov I.Pivovarov Budker Institute of Nuclear Physics Lavrentyeva Av.11NovosibirskRussia630090 Novosibirsk state University Pirogova Str.2NovosibirskRussia630090

This paper details the development and testing of the first working prototype of the s-band high-power klystron,accomplished at the Budker Institute of Nuclear Physics,siberian Branch,Russian Academy of sciences(BINP sB RAs).Upon testing,the klystron demonstrated the following parameters:an operating frequency of 2856 MHz and a peak power output of 50 *** paper presents the klystron's design,its constituent units,and pertinent processing procedures,along with discussions on the measurement of its parameters.

关键词： Klystron Linear accelerator Electron beam

Metric and Upper Dimension of Extended Annihilating-Ideal Graphs

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Algebra Colloquium 2024年第2期31卷 221-238页

作者： s.Nithya G.Elavarasi Genghua Fan Department of Mathematics St.Xavier's College(Autonomous)Palayamkottai 627002Tamil NaduIndia Afiliated to Manonmaniam sundaranar University Abishekapatti Tirunelveli 627012Tamil NaduIndia PG and Research Department of Mathematics St.Xavier's College(Autonomous)Palayamkottai 627002Tamil NaduIndia Affiliated to Manonmaniam sundaranar University Abishekapatti Tirunelveli 627012Tamil NaduIndia 不详

The metric dimension problem is called navigation problem due to its application to robot navigation in *** this concept has wide applications in motion planning,sonar and loran station,and so *** this paper,we study certain results on the metric dimension,upper dimension and resolving number of extended annihilating-ideal graph EAG(R)associated to a commutative ring R,denoted by dim M(EAG(R)),dim+(EAG(R))and res(EAG(R)),*** we prove the finiteness conditions of dim M(EAG(R))and dim+(EAG(R)).In addition,we characterize dim M(EAG(R)),dim+(EAG(R))and res(EAG(R))for artinian rings and the direct product of rings.

关键词： extended annihilating-ideal graph metric dimension upper dimension resolving number

A comprehensive analysis of future solar energy potential variations using a CMIP6 multi-model ensemble approach in Colombia

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Clean Energy 2024年第4期8卷 79-89页

作者： Heli AArregocés Roberto Rojano Daiver Pinto Pimienta Grupo de Investigación GIsA Facultad de IngenieríaUniversidad de La GuajiraRiohachaColombia Grupo Procesos Fisicoquímicos Aplicados Facultad de IngenieríaUniversidad de Antioquia SIU/UdeACalle 70 No.52–21MedellínColombia Grupo Desarrollo de Estudios y Tecnologías Ambientales del Carbono(DEsTACAR) Facultad de IngenieríaUniversidad de La GuajiraRiohachaColombia

Climate change is predicted to significantly impact solar energy generation,which is particularly concerning given that photovoltaic(PV)energy is critical to the global transition to clean energy in underdeveloped *** study analyses the PV potential variations in Colombia using a Coupled Model Intercomparison Project Phase 6(CMIP6)multi-model ensemble approach under two shared socio-economic pathway scenarios for the near(2025-50)and far(2051-2100)*** the near-future period,the Pacific,Andean and Orinoquía regions are expected to experience a decrease in PV potential ranging from 10%to 23%for all shared socio-economic *** will be particularly noticeable during the March/April/May and June/July/August *** the other hand,CMIP6 estimations indicate a 1-4%increase in PV potential across the Amazon region during the June/July/August and september/October/November *** the far future,it has been projected that the Pacific,Andean and Orinoquía regions may experience a significant decline in solar power generation due to increased cloud cover and reduced *** decrease in PV potential during the June/July/August season could range from 8%to 27%for all considered scenarios,with the Pacific region being the most *** Pacific region is projected to experience a decrease ranging from 10%to 35%for all *** is worth noting that there are noticeable differences in PV potential across various regions,which can result in changes in cloud cover and atmospheric ***,the study provides valuable insights into the PV potential in Colombia and highlights the importance of considering regional variations and climate change scenarios in future energy planning.

关键词： photovoltaic potential CMIP6 solar photovoltaic energy climate change Colombia

A tribo-chemical view on astringency of plant-based food substances

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Friction 2024年第7期12卷 1392-1407页

作者： samuel s.GAMANIEL Paloma s.DUEÑAs ROBLEs Hans TROMP Els H.A.de HOOG sissi de BEER Emile van der HEIDE Laboratory for surface Technology and Tribology Faculty of Engineering TechnologyUniversity of TwenteEnschede 7522 LWthe Netherlands NIZO Food Research B.V. Ede6710 BAthe Netherlands Department of Molecules and Materials MEsA+Institute for Nanotechnology University of TwenteEnschede 7500 AEthe Netherlands

Consumption of plant-based food products having high composition of polyphenols leads to the sensation of *** sliding oral surfaces,friction is an essential property during the oral perception of roughness and dryness which are attributes associated with *** factors including the chemical composition of interacting layers,structure and operation of interfaces have an effect on the astringency development *** manner of interactions occurring at oral interfaces suggest there is a system dependence of astringency and highlights the importance of adopting a tribosystems *** measurement techniques have shown an existing relationship between salivary protein-polyphenol interaction and an astringent ***,the tribo-chemistry involved in this multifaceted sensation remains largely unexplored in a comprehensive *** this review the underlying tribo-chemical processes useful in understanding the mechanism of astringency are highlighted and discussed considering current techniques employed to investigate astringency *** of lubrication on oral surfaces owing to the tribo-chemical interactions involving saliva and astringent plant proteins requires subsequent deformations of oral tissues which are significant enough to induce strains at mechanoreceptor locations,leading to the sensation of *** is proposed that micro-scale contact modelling on the interaction of food particles/aggregates,boundary layers and oral surfaces shows potential in addressing the knowledge gap between tribo-chemical measurement techniques and panel tests,making it possible to attain a predictor for astringency.

关键词： oral lubrication astringency tribo-chemistry tribology

Editor-in-Chief articles of choice and comments at the year-end of 2023

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World Journal of Gastroenterology 2024年第1期30卷 1-8页

作者： Andrzej s Tarnawski Department of Gastroenterology Research University of California Irvine and the Veterans Administration Long Beach Healthcare SystemLong BeachCA 90822United States

As the Editor-in-Chief of World Journal of Gastroenterology,every week prior to a new issue’s online publication,I perform a careful review of all encompassed articles,including the title,clinical and/or research importance,originality,novelty,and ratings by the peer *** on this review,I select the papers of choice and suggest pertinent changes(e.g.,in the title)to the Company Editors responsible for *** process,while time-consuming,is very important for assuring the quality of publications and highlighting important articles that Readers may revisit.

关键词： Papers of choice Careful weekly review suggested changes/revisions Hepatocellular carcinoma Pancreatic cancer Liver cirrhosis Liver injury Gastric cancer Colorectal cancer Inflammatory bowel diseases