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Constraining the f(R,T)=R+2λT cosmological model using recent observational data

Chinese Physics C 2023年第11期47卷 167-176页

作者： N.Myrzakulov M.Koussour Alnadhief H.A.Alfedeel e.i.hassan L.N.Gumilyov eurasian National University Astana 010008Kazakhstan Ratbay Myrzakulov eurasian international Centre for Theoretical Physics Astana 010009Kazakhstan Quantum Physics and Magnetism Team LPMCFaculty of Science Ben M'sikCasablanca Hassan II UniversityMorocco Department of Mathematics and Statistics Imam Mohammad Ibn Saud Islamic University(IMSIU)Riyadh 13318Saudi Arabia Department of Physics Faculty of ScienceUniversity of KhartoumP.O.Box 321Khartoum 11115Sudan Centre for Space Research North-West UniversityPotchefstroom 2520South Africa

in this study,we conduct a comprehensive investigation of the cosmological model described by f(R,T)=R+2λT(whereλrepresents a free parameter)in light of the most recent observational *** constraining the model using the Hubble and Pantheon datasets,we determine its compatibility with the observed behavior of the *** this purpose,we adopt a parametric form for the effective equation of state(eoS)*** parametric form allows us to describe the evolution of the eoS parameter with respect to redshift and investigate its behavior during different cosmic *** analysis of the deceleration parameter reveals an accelerating Universe with a present value of q0=−0.64_(−0.03)^(+0.03),indicating the current phase of accelerated *** transition redshift is found to be ztr=0.53_(−0.03)^(+0.04),marking the epoch of transition from deceleration to *** also analyze the evolution of important cosmological parameters,including the density parameter,pressure,effective eoS,and *** findings collectively demonstrate the viability of the f(R,T)cosmological model as a robust candidate capable of engendering the requisite negative pressure,thereby efficiently propelling cosmic ***,the undertaken stability analysis underscores the model's stability within the broader cosmic *** providing the best-fit values for the coupling parameterλ,this approach motivates and encourages further exploration into the extensive landscape of this model and its potential applications across diverse realms of cosmology and astronomy.

关键词： f(R,T)gravity eoS parameter observational constraints dark energy

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Square-root parametrization of dark energy in f(Q)cosmology

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Communications in Theoretical Physics 2023年第12期75卷 105-114页

作者： M Koussour N Myrzakulov Alnadhief H A Alfedeel e i hassan D Sofuoğlu Safa M Mirgani Quantum Physics and Magnetism Team LPMCFaculty of Science Ben M'sikCasablanca Hassan II University L.N.Gumilyov eurasian National University Ratbay Myrzakulov eurasian international Centre for Theoretical Physics Department of Mathematics and Statistics Imam Mohammad Ibn Saud Islamic University(IMSIU) Department of Physics Faculty of ScienceUniversity of Khartoum Centre for Space Research North-West University Department of Physics Istanbul University Vezneciler 34134

This paper is a parametrization of the equation of state(eo S)parameter of dark energy(De),which is parameterized using square-root(SR)form i.e.ω_(SR)=ω_(0)+ω_(1)z/√z^(2)+1,where ω_(0)and ω_(1) are free *** parametrization is examined in the context of the recently suggested f(Q)gravity theory as an alternative to general relativity(GR),in which gravitational effects are attributed to the non-metricity scalar Q with the functional form f(Q)=Q+αQ^(n),whereαand n are arbitrary *** derive observational constraints on model parameters using the Hubble dataset with 31 data points and the Supernovae(SNe)dataset from the Pantheon samples compilation dataset with 1048 data *** the current model,the evolution of the deceleration parameter,density parameter,eoS for De,and Om(z)diagnostic have all been *** has been shown that the deceleration parameter favors the current accelerated expansion *** has also been shown that the eoS parameter for De has a quintessence nature at this time.

关键词： cosmology dark energy f(Q)gravity eoS parameter

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The sexually dimorphic expression of glutamate transporters and their implication in pain after spinal cord injury

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Neural Regeneration Research 2025年第11期20卷 3317-3329页

作者： Jennifer M.Colón-Mercado Aranza i.Torrado-Tapias iris K.Salgado Jose M.Santiago Samuel e.Ocasio Rivera Dina P.Bracho-Rincon Luis H.Pagan Rivera Jorge D.Miranda Department of Physiology University of Puerto RicoMedical Sciences CampusSan JuanPRUSA National institutes of Health National Human Genome Research InstituteBethesdaMDUSA Universidad Central del Caribe School of MedicineBayamónPRUSA University of Puerto Rico Carolina CampusCarolinaPRUSA institute of Neurobiology San JuanPRUSA

in addition to the loss of motor function,~60% of patients develop pain after spinal cord *** cellular-molecular mechanisms are not well understood,but the data suggests that plasticity within the rostral,epicenter,and caudal penumbra of the injury site initiates a cellularmolecular interplay that acts as a rewiring mechanism leading to central neuropathic *** can lead to the formation of new connections triggering abnormal sensory *** excitatory glutamate transporters are responsible for the reuptake of extracellular glutamate which makes them a critical target to prevent neuronal hyperexcitability and *** previous studies showed a sexually dimorphic therapeutic window for spinal cord injury after treatment with the selective estrogen receptor modulator *** this study,we investigated the anti-allodynic effects of tamoxifen in male and female rats with spinal cord *** hypothesized that tamoxifen exerts anti-allodynic effects by increasing the expression of glutamate transporters,leading to reduced hyperexcitability of the secondary neuron or by decreasing aberrant *** and female rats received a moderate contusion to the thoracic spinal cord followed by subcutaneous slow-release treatment of tamoxifen or matrix pellets as a control(placebo).We used von Frey monofilaments and the“up-down method”to evaluate mechanical *** treatment decreased allodynia only in female rats with spinal cord injury revealing a sexdependent *** expression profile of glutamatergic transporters(excitatory amino acid transporter 1/glutamate aspartate transporter and excitatory amino acid transporter 2/glutamate transporter-1)revealed a sexual dimorphism in the rostral,epicenter,and caudal areas of the spinal cord with a pattern of expression primarily on *** rodents showed a significantly higher level of excitatory amino acid transporter-1 expression while male rodents showed increased

关键词： allodynia central neuropathic pain eAAT-1/GLAST eAAT-2/GLT-1 glutamate transporters selective estrogen receptor modulator sexual dimorphism spinal cord injury trauma

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effects of the phase variation and high-order momentum transfer components of NN amplitude on p-~4He elastic scattering

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Nuclear Science and Techniques 2018年第1期29卷 65-76页

作者： i.M.A.Tag-eldin M.M.Taha S.S.A.hassan Nuclear experimental Physics Department Nuclear Research Center Atomic Energy Authority Mathematics and Theoretical Physics Department Nuclear Research Center Atomic Energy Authority

elastic scattering differential cross sections for a p- ~4He system are calculated within the framework of optical limit approximation of the Glauber multiple scattering model. Three different ranges for proton energy(e_(lab)), 19〈e_(lab)〈50 Me V, 100≤e_(lab)≤1730 Me V, and 45 ≤e_(lab)≤393 Ge V are considered. it is shown that the Pauli blocking fails to describe the data up to the proton energy, e_(lab)〈100 Me V. For higher proton energies, a qualitative agreement is obtained. The observed elastic scattering differential cross section is nicely reproduced in the whole range of scattering angles in the center of mass system up to Θ_(c.m.)〈200° for 19〈e_(lab) ≤100 Me V when the effect of both the nucleon–nucleon(NN) phase variation parameter γNN and higher-order momentum transfer components(λ_n; n = 1 and 2) of(NN) elastic scattering amplitude is included. in the range of 200 e_(lab) 1730 Me V, introducing λ_n plays a significant role in describing the data up to the momentum transfer, q^2≤1:2(Ge V/c)~***, it is found that considering only the effect of phase variation parameter, cNN, improved the agreement in the region of minima for elastic scattering differential cross section for 45≤e_(lab)≤393 Ge V. The values of cNNand kn as a function of incident proton energies are presented.

关键词： elastic scattering Optical limit approximation Glauber multiple scattering model

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Classifying Misinformation of User Credibility in Social Media Using Supervised Learning

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Computers, Materials & Continua 2023年第5期75卷 2921-2938页

作者： Muhammad Asfand-e-Yar Qadeer Hashir Syed hassan Tanvir Wajeeha Khalil Department of Computer Science Center of Excellence in Artificial Intelligence(CoE-AI)Bahria UniversityIslamabad44000Pakistan Department of Computer Science and information Technology University of Engineering and TechnologyPeshawar25000Pakistan

The growth of the internet and technology has had a significant effect on social *** information has become an important research topic due to the massive amount of misinformed content on social *** is very easy for any user to spread misinformation through the ***,misinformation is a problem for professionals,organizers,and ***,it is essential to observe the credibility and validity of the News articles being shared on social *** core challenge is to distinguish the difference between accurate and false *** studies focus on News article content,such as News titles and descriptions,which has limited their ***,there are two ordinarily agreed-upon features of misinformation:first,the title and text of an article,and second,the user *** the case of the News context,we extracted different user engagements with articles,for example,tweets,i.e.,read-only,user retweets,likes,and *** calculate user credibility and combine it with article content with the user’s *** combining both features,we used three Natural language processing(NLP)feature extraction techniques,i.e.,Term Frequency-inverse Document Frequency(TF-iDF),Count-Vectorizer(CV),and Hashing-Vectorizer(HV).Then,we applied different machine learning classifiers to classify misinformation as real or ***,we used a Support Vector Machine(SVM),Naive Byes(NB),Random Forest(RF),Decision Tree(DT),Gradient Boosting(GB),and K-Nearest Neighbors(KNN).The proposed method has been tested on a real-world dataset,i.e.,“fakenewsnet”.We refine the fakenewsnet dataset repository according to our required *** dataset contains 23000+articles with millions of user *** highest accuracy score is 93.4%.The proposed model achieves its highest accuracy using count vector features and a random forest *** discoveries confirmed that the proposed classifier would effectively classify misinformat

关键词： Misinformation user credibility fake news machine learning

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Peak-to-average power ratio reduction using selective mapping with unequal power distribution

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Journal of Central South University 2012年第7期19卷 1902-1908页

作者： e.S.hassan XU Zhu S.e.e1-Khamy M.i.Dessouky S.A.ei-Dolill F.e.Abd ei-Samie Department of electronics and electrical Communications Faculty of Electronic EngineeringMenoufia UniversityMenouf 32952Egypt Department of electrical engineering and electronics The University of LiverpoolLiverpool L693G JUK Department of electrical engineering Faculty of EngineeringAlexandria UniversityAlexandria 21544Egypt

A new approach for peak-to-average power ratio (PAPR) reduction in orthogonal frequency division multiplexing (OFDM) systems was *** approach is based on assigning powers to the different subcarriers of OFDM using an unequal power distribution *** addition,a reduced complexity selective mapping (RC-SLM) scheme was *** proposed scheme is based on partitioning the frequency domain symbol sequence into several sub-blocks,and then each sub-block is multiplied by different phase sequences whose length is shorter than that used in the conventional SLM ***,a kind of low complexity conversions is used to replace the iFFT *** performance of the proposed RC-SLM scheme along with the new approach was studied with computer *** obtained results show that the proposed RC-SLM scheme is able to achieve the lowest computational complexity when compared with other low complexity schemes proposed in the literature while at the same time improves the PAPR reduction performance by about 0.3 dB.

关键词： orthogonal frequency division multiplexing (OFDM) peak-to-average power ratio (PAPR) computational complexity selective mapping scheme

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Cyclic Stability of Superelasticity in[001]‑Oriented Quenched Ni_(44)Fe_(19)Ga_(27)Co_(10)and Ni_(39)Fe_(19)Ga_(27)Co_(15)Single Crystals

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Acta Metallurgica Sinica(english Letters) 2023年第4期36卷 650-660页

作者： e.e.Timofeeva e.Yu.Panchenko A.S.eftifeeva A.i.Tagiltsev N.Yu.Surikov A.B.Tokhmetova e.i.Yanushonite M.V.Zherdeva i.Karaman Yu.i.Chumlyakov Tomsk State University Novosobornaya Square 1Tomsk 634050Russia Texas A&M University College StationTX 77843USA

The study of the influence of the cobalt content on the cyclic stability of superelasticity(Se)was carried out in quenched Ni_(44)Fe_(19)Ga_(27)Co_(10)and Ni_(39)Fe_(19)Ga_(27)Co_(15)(at.%)single crystals under *** is shown that an increase in the cobalt content leads to embrittlement of the material and a decrease in the cyclic stability of *** Ni_(44)Fe_(19)Ga_(27)Co_(10)single crystals,during the first 20 loading/unloading cycles,the elastic energy relaxation occurs along with the formation of dislocations and residual martensite,which leads to a decrease in critical stress of martensite formation and in stress *** the next 80 cycles,Se becomes more *** is accompanied by a slight change in the *** the contrary,Ni_(39)Fe_(19)Ga_(27)Co_(15)single crystals are characterized by high-strength characteristics,which lead to high Se stability during the first 20 loading/unloading ***,after 20 cycles,a strong degradation of the Se is observed through the formation of microcracks,which ultimately leads to the destruction of the *** results of work are replicable for cycling at different temperatures from all temperature ranges of superelasticity.

关键词： Martensitic transformations Superelasticity Single crystals Cyclic stability Microstructure

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Preparation,quality control and biodistribution of [^(61)Cu]-doxorubicin for PeT imaging

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Nuclear Science and Techniques 2009年第3期20卷 157-162页

作者： JALiLiAN Amir Reza YOUSeFNiA hassan FAGHiHi Reza AKHLAGHi Mehdi ZANDi hassan Nuclear Medicine Research Group Agricultural Medical and Industrial Research School Karaj Iran Department of Nuclear engineering School of Engineering Shiraz University Shiraz Iran

This work was conducted for radiolabeling of an anticancer antibiotic, i.e. doxorubicin with 61Cu for production of possible tracer used in PeT oncology. 61Cu was prepared with natural zinc target and 22 MeV150 μA protons via natZn(p, xn)61Cu reaction with a yield of 123.2 MBq·μA-1·h-1. Optimization reactions were performed for pH, temperature and concentration. Biodistribution of the tracer was studied in normal and fibrosarcoma bearing mice. At the optimized conditions, iTLC showed that radiochemical purity was over 97% with a specific activity of 2.22× 103MBq ·mmol-1·L-1. This was kept unchanged even with presence of human serum as well as room temperature for 5 h. Biodistribution of the tracer in fibrosarcoma bearing mice demonstrated significant tumor uptake after 2 h. This tracer can be used in the detection of various tumors responding to doxorubicin chemotherapy using PeT scan and/or determination of tumor therapy response to doxorubicin chemotherapy.

关键词：放射性元素研究核技术 ^61Cu

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enhancing perianal disease management with integrated physical and psychological approaches

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World Journal of Clinical Cases 2025年第2期13卷 59-63页

作者： Uchenna e Okpete Haewon Byeon Department of Digital Anti-aging Healthcare(BK21) Inje UniversityGimhae 50834South Korea

This article provides a comprehensive analysis of the study by Hou et al,focusing on the complex interplay between psychological and physical factors in the postoperative recovery(POR)of patients with perianal *** study sheds light on how illness perception,anxiety,and depression significantly influence recovery *** et al developed a predictive model that demonstrated high accuracy in identifying patients at risk of poor *** article explores the critical role of pre-operative psychological assessment,highlighting the need for mental health support and personalized recovery plans in enhancing POR quality.A multidisciplinary approach,integrating mental health professionals with surgeons,anesthesiologists,and other specialists,is emphasized to ensure comprehensive care for *** study’s findings serve as a call to integrate psychological care into surgical practice to optimize outcomes for patients with perianal diseases.

关键词： Perianal disease Post-operative recovery Anxiety Depression Pain management emotional well-being Multidisciplinary approach

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Tungsten ion source under double-pulse laser ablation system

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Chinese Physics B 2017年第9期26卷 285-296页

作者： Ahmed Asaad i Khalil Ashraf i Hafez Mahmoud e elgohary Mohamed A Morsy Department of Laser Sciences and interactions National Institute of Laser Enhanced SciencesCairo UniversityGiza 12613Egypt Central Laboratory of Ministry of electricity CairoEgypt Atomic Research Center Atomic Energy AuthorityCairo 13759Egypt Department of Nuclear engineering Jordan University of Science and Technology IrbidJordan Department of Chemistry King Fahd University of Petroleum and MineralsDhahran 31261Saudi Arabia

New tungsten ion source is produced by using single and double-pulse laser ablation system. Combined collinear Nd：YAG laser beams（266＋1064 nm） are optimized to focus on the sample in air. Optimization of the experimental parameters is achieved to enhance the signal-to-noise ratio of the emission spectra. The velocity distribution of the emitted plasma cloud is carefully measured. The influences of the potential difference between the bias electrodes, laser wavelength and intensity on the current signal are also studied. The results show that the increase in the tungsten ion velocity under the double-pulse lasers causes the output current signal to increase by about three folds. The electron density and temperature are calculated by using the Stark-broadened line profile of tungsten line and Boltzmann plot method of the upper energy levels, respectively. The signal intensity dependence of the tungsten ion angular distribution is also analyzed. The results indicate that the double-pulse laser ablation configuration is more potent technique for producing more metal ion source deposition, thin film formation, and activated plasma-facing component material.

关键词： tungsten ion beam double-pulse lasers ablation system laser ablation system optical instrumentation

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