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Higgs-like(pseudo)scalars in Ads_(4),marginal and irrelevant deformations in CFt_(3),and instantons on s^(3)

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Chinese Physics C 2024年第4期48卷 68-81页

作者： m.Naghdi Department of Physics Faculty of Basic SciencesUniversity of IlamIlamIran

Employing a 4-form ansatz of 11-dimensional supergravity over a non-dynamical Ads_(4)×s^(7)/Z_(k)background and setting the internal space as an s1 Hopf fibration on CP3,we obtain a consistent ***(pseudo)scalars,in the resulting scalar equations in Euclidean Ads_(4)space,may be considered to arise from(anti)m-branes wrapping around the internal directions in the(wick-rotated)skew-whiffed m2-brane background(as the resulting theory is for anti-m2-branes),thus realizing the modes after swapping the three fundamental representations 8_(s),8_(c),and 8_(v) of sO(8).taking the backreaction on the external and internal spaces,we obtain the massless and massive modes,corresponding to exactly marginal and marginally irrelevant deformations on the boundary CFt3,***,we obtain a closed solution for the bulk equation and compute its correction with respect to the background ***,considering the Higgs-like(breathing)mode m^(2)=18,having all supersymmetries as well as parity and scale-invariance broken,solving the associated bulk equation with mathematical methods,specifically the Adomian decomposition method,and analyzing the behavior near the boundary of the solutions,we realize the boundary duals in the sU(4)×U(1)-singlet sectors of the ABJm ***,introducing the new dual deformationΔ_(+)=3,6 operators made of bi-fundamental scalars,fermions,and U(1)gauge fields,we obtain the sO(4)-invariant solutions as small instantons on a three-sphere with the radius at infinity,which correspond to collapsing bulk bubbles leading to big-crunch singularities.

关键词： Ads_(4)/CFt_(3)correspondence scalar equations in Ads_(4) instantons marginal and irrelevant operators (anti)m-branes

synthetic polymers:A review of applications in drilling fluids

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Petroleum science 2024年第1期21卷 475-518页

作者： shadfar Davoodi mohammed Al-shargabi David A.wood Valeriy s.Rukavishnikov Konstantin m.minaev school of Earth sciences&Engineering Tomsk Polytechnic UniversityLenin AvenueTomskRussia DwA Energy Limited LincolnUnited Kingdom

with the growth of deep drilling and the complexity of the well profile,the requirements for a more complete and efficient exploitation of productive formations increase,which increases the risk of various ***,reagents based on modified natural polymers(which are naturally occurring compounds)and synthetic polymers(sPs)which are polymeric compounds created industrially,are widely used to prevent emerging complications in the drilling ***,compared to modified natural polymers,sPs form a family of high-molecular-weight compounds that are fully synthesized by undergoing chemical polymerization *** provide substantial flexibility in their ***,their size and chemical composition can be adjusted to provide properties for nearly all the functional objectives of drilling *** can be classified based on chemical ingredients,type of reaction,and their responses to ***,some of sPs,due to their structural characteristics,have a high cost,a poor temperature and salt resistance in drilling fluids,and degradation begins when the temperature reaches 130℃.these drawbacks prevent sP use in some medium and deep ***,this review addresses the historical development,the characteristics,manufacturing methods,classification,and the applications of sPs in drilling *** contributions of sPs as additives to drilling fluids to enhance rheology,filtrate generation,carrying of cuttings,fluid lubricity,and clay/shale stability are explained in *** mechanisms,impacts,and advances achieved when sPs are added to drilling fluids are also *** typical challenges encountered by sPs when deployed in drilling fluids and their advantages and drawbacks are also *** issues also impact the applications of sPs in drilling ***,the cost of the most relevant sPs,and the monomers used in their synthesis,are *** impacts of sPs when deployed in drilling fluids,and t

关键词： synthetic versus natural polymers Nanopolymers Drilling fluid additives Lubricity Clay swelling Hole cleaning

Failure pattern in ceramic metallic target under ballistic impact

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Defence technology（防务技术） 2024年第10期40卷 173-190页

作者： m.A.Iqbal m.K.Khan Department of Civil Engineering Indian Institute of Technology RoorkeeRoorkee 247667India Department of Civil Engineering Aligarh Muslim UniversityAligarh202002India

the ballistic resistance and failure pattern of a bi-layer alumina 99.5%-aluminium alloy 1100-H12 target against steel 4340 ogival nosed projectile has been explored in the present experimental cum numerical *** the experimental investigation,damage induced in the ceramic layer has been quantified in terms of number of cracks developed and failure zone *** resultant damage in the backing layer has been studied with variation in the bulge and perforation hole in the backing layer with the varying incidence *** discussion of the experimental results has been further followed by three dimensional finite element computations using ABAQUs/Explicit finite code to investigate the behaviour of different types of bi-layer targets under multi-hit projectile *** JH-2 constitutive model has been used to reproduce the behaviour of alumina 99.5%and JC constitutive model has been used for steel 4340 and aluminium alloy *** total energy dissipation has been noted to be of lesser magnitude in case of sub-sequential impact in comparison to simultaneous impact of two *** distance between the impact points of two projectiles also effected the ballistic resistance of bi-layer *** ballistic resistance of single tile ceramic front layer and four tile ceramic of equivalent area found to be dependent upon the boundary conditions provided to the target.

关键词： Ballistic resistance Bi-layer target Ceramic metal armour multi-hit impact Finite element modelling

A review of control strategies used for morphing aircraft applications

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Chinese Journal of Aeronautics 2024年第4期37卷 436-463页

作者： muhammed s.PARANCHEERIVILAKKAtHIL Jafar s.PILAKKADAN Rafic m.AJAJ mohammadreza AmOOZGAR Davood AsADI Yahya ZwEIRI michael I.FRIswELL Department of Aerospace Engineering Khalifa University of Science and TechnologyAbu DhabiUnited Arab Emirates Department of Aerospace Engineering Advanced Research and Innovation Center(ARIC)Khalifa University of Science and TechnologyAbu DhabiUnited Arab Emirates Department of mechanical Materials&Manufacturing EngineeringUniversity of NottinghamNottingham NG72RDUK Department of Aerospace Engineering Adana Alparslan Turkes Science and Technology UniversityTurkey College of Engineering Swansea UniversitySwansea SA18ENUK

this paper reviews the various control algorithms and strategies used for fixed-wing morphing aircraft applications. It is evident from the literature that the development of control algorithms for morphing aircraft technologies focused on three main areas. the first area is related to precise control of the shape of morphing concepts for various flight conditions. the second area is mainly related to the flight dynamics, stability, and control aspects of morphing aircraft. the third area deals mainly with aeroelastic control using morphing concepts either for load alleviation purposes and/or to control the instability boundaries. the design of controllers for morphing aircraft/wings is very challenging due to the large changes that can occur in the structural, aerodynamic, and inertial characteristics. In addition, the type of actuation system and actuation rate/speed can have a significant effect on the design of such controllers. the aerospace community is in strong need of such a critical review especially as morphing aircraft technologies move from fundamental research at a low technology Readiness Level(tRL) to real-life applications. this critical review aims to identify research gaps and propose future directions. In this paper, research activities/papers are categorized according to the control strategy used. this ranges from simple Proportional Integral Derivative(PID) controllers at one end to complex robust adaptive controllers and deep learning algorithms at the other end. this includes analytical, computational, and experimental studies. In addition, the various dynamic models used and their fidelities are highlighted and discussed.

关键词： Control strategies morphing aircraft shape morphing Flight dynamics Aeroelasticity

surface activation of viscose textiles via air,argon,and oxygen dielectric barrier discharge plasma:influence of peak voltage

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Plasma science and technology 2024年第7期26卷 134-147页

作者： shrouk ELAsHRY Usama m.RAsHED mostafa A.wAHBA Hend m.AHmED Nabil m.ELsIRAGY Plasma Laboratory Physics DepartmentFaculty of scienceTanta UniversityTanta 31527Egypt Physics Department Faculty of Science(Male)Al-Azhar UniversityCairo 11651Egypt textile Research Industrial Division National Research CentreDokkiGiza 12622Egypt

this paper discusses the use of atmospheric pressure dielectric barrier discharge(DBD)plasma treatment to enhance the surface qualities of viscose *** study explores the effects of different plasma gases,discharge voltages,and exposure times on the treated *** findings emphasize the importance of optimizing the plasma's peak voltage to achieve the desired surface treatment *** document also presents data on colour strength,wettability,colour fastness,and tensile strength of the treated fabrics,as well as scanning electron microscopy(sEm)analysis of surface morphology and chemical analysis using fouriertransition infrared spectroscopy(FtIR)and energy dispersive X-ray(EDX).the results show that treatment at a peak voltage of 11.83 k V is more efficient,except for the tensile strength which is enhanced at a peak voltage of 8.92 k *** oxygen plasma treatment significantly improves the colour strength,which exhibits an increase from 11 to *** intensified colour was attributed to the significant influence of electrostatic interactions between the charged hydroxyl groups of the oxygen plasma treated viscose textiles and the dye molecules,which enhance the *** oxygen DBD plasma exhibits a higher ability to enhance the properties of textiles when compared to air and argon *** study presents a sustainable,economical,secure,and ecologically friendly approach to explore new fabrics for specific uses.

关键词： Lissajous diagrams printability wettability tensile strength sEm EDX FtIR

C-phycocyanin shows neuroprotective effect against rotenone-induced Parkinson’s disease in mice

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Asian Pacific Journal of tropical Biomedicine 2024年第7期14卷 279-287页

作者： Hritik Rathod Ritu m.soni Jigna s.shah Department of Pharmacology Institute of Pharmacy Nirma UniversityAhmedabadGujaratIndia

Objective:to investigate the neuroprotective effect of C-phycocyanin in a mouse model of rotenone-induced Parkinson’s ***:C-phycocyanin(50 mg/kg,i.p.,daily)was administered to rotenone(30 mg/kg,p.o.,daily)treated mice for 28 *** studies(Y-maze,rotarod,round beam walk,and wire-hang tests)were carried out to assess neurobehavioral *** and malondialdehyde were determined in both serum and striatal *** proteins(AKt,AmPK,NF-κB,BDNF,and alpha-synuclein)in the striatum were estimated using *** analyses(hematoxylin and eosin stainning as well as Nissl staining)were carried out to assess structural abnormalities in the ***:C-phycocyanin significantly increased BDNF levels and decreased alpha-synuclein *** also slightly upregulated AmPK and AKt levels without significant difference compared with the rotenone ***,rotenone-induced elevated oxidative stress and structural abnormalities in the striatum were markedly mitigated by ***:C-phycocyanin might have potential neuroprotective effects against Parkinson’s *** studies are warranted to verify its efficacy and to understand the molecular mechanisms behind the neuroprotective effects of C-phycocyanin in Parkinson’s disease.

关键词： Parkinson’s disease C-phycocyanin Alphasynuclein BDNF Oxidative stress Rotenone

Provenance and depositional setting of the Late miocenePleistocene clastic sediments in the eastern Arabian Peninsula and western Iraq using rare earth elements geochemistry

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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

A parsimonious Bayesian predictive model for forecasting new reported cases of west Nile disease

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Infectious Disease modelling 2024年第4期9卷 1175-1197页

作者： saman Hosseini Lee w.Cohnstaedt John m.Humphreys Caterina scoglio Department of Electrical and Computer Engineering Kansas State UniversityManhattanKSUSA Foreign Arthropod-Borne Animal Diseases Research Unit National Bio-and Agro-defense Facility USDA ARSManhattanKSUSA Foreign Animal Disease Research Unit National Bio-and Agro-defense FacilityUSDA ARSManhattanKSUSA

Upon researching predictive models related towest Nile virus disease,it is discovered that there are numerous parameters and extensive information in most models,thus contributing to unnecessary *** challenge frequently encountered is the lead time,which refers to the period for which predictions are made and often is too *** paper addresses these issues by introducing a parsimonious method based on ICC curves,offering a logistic distribution model derived from the vector-borne sEIR *** existing models relying on diverse environmental data,our approach exclusively utilizes historical and present infected human cases(number of new cases).with a yearlong lead time,the predictions extend throughout the 12 months,gaining precision as new data *** conditions are derived to minimize Bayesian loss,enhancing predictive *** construct a Bayesian forecasting probability density function using carefully selected prior *** these functions,we predict monthspecific infections nationwide,rigorously evaluating accuracy with probabilistic ***,HPD credible intervals at 90%,95%,and 99%levels is *** assessment is conducted for HPD intervals,measuring the proportion of intervals that does not include actual reported cases for 2020e2022.

关键词： west nile virus ICC curve Bayesian model Logistic distribution HPD credible interval

Artificial Intelligence Prediction of One-Part Geopolymer Compressive strength for sustainable Concrete

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Computer modeling in Engineering & sciences 2024年第10期141卷 525-543页

作者： mohamed Abdel-mongy mudassir Iqbal m.Farag Ahmed.m.Yosri Fahad Alsharari saif Eldeen A.s.Yousef Department of Civil Engineering College of EngineeringJouf UniversitySakaka72388Saudi Arabia Department of Civil Engineering University of Engineering and TechnologyPeshawar54890Pakistan Civil Engineering Department Faculty of EngineeringAl-Azhar UniversityCairo11884Egypt Civil Engineering Department Faculty of EngineeringAswan UniversityAswan81528Egypt

Alkali-activated materials/geopolymer(AAms),due to their low carbon emission content,have been the focus of recent studies on ecological *** terms of performance,fly ash and slag are preferredmaterials for precursors for developing a one-part ***,determining the optimum content of the input parameters to obtain adequate performance is quite challenging and scarcely ***,in this study,machine learning methods such as artificial neural networks(ANN)and gene expression programming(GEP)models were developed usingmAtLAB and GeneXprotools,respectively,for the prediction of compressive strength under variable input materials and content for fly ash and slag-based one-part *** database for this study contains 171 points extracted from literature with input parameters:fly ash concentration,slag content,calcium hydroxide content,sodium oxide dose,water binder ratio,and curing *** performance of the two models was evaluated under various statistical indices,namely correlation coefficient(R),mean absolute error(mAE),and rootmean square error(RmsE).In terms of the strength prediction efficacy of a one-part geopolymer,ANN outperformed *** and parametric analysis were also performed to identify the significant contributor to *** to a sensitivity analysis,the activator and slag contents had the most effects on the compressive strength at 28 *** water binder ratio was shown to be directly connected to activator percentage,slag percentage,and calcium hydroxide percentage and inversely related to compressive strength at 28 days and curing temperature.

关键词： Artificial intelligence techniques one-part geopolymer artificial neural network gene expression modelling sustainable construction polymers