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Complexity of charged anisotropic spherically symmetric fluids in f(G)gravity

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Communications in Theoretical Physics 2023年第3期75卷 91-104页

作者： z yousaf M z Bhatti M M M Nasir Department of Mathematics University of the PunjabQuaid-i-Azam CampusLahore-54590Pakistan

The previous ideology of complexity factor for the dynamical spheres[Herrera et al 2018,Phys.Rev.D,98,104059]is extended for the influence of charge.A dynamical spherically symmetric non-dissipative and dissipative self-gravitating structure is examined in the presence of Maxwell f(G)gravity to examine the complexity factor.The pattern of evolution is studied with the minimal complexity constraint.The complexity factor remains the same for the structure of fluid distribution,while we examine homologous constraints for the most basic evolution pattern.We calculate the structure scalars which play an important role in order to understand the fundamental properties of the system.The fluid is geodesic as well as shearing for the dissipative case and there is a large number of solutions.In the non-dissipative fluid distribution,a shear-free,homogeneous and isotropic,geodesic fluid correlates with the evolving homologous and vanishing complexity condition.The implication of the condition of vanishing complexity factor and stability are discussed at the end.

关键词： gravitation anisotropy complexity hydrodynamics

Shearfree Spherically Symmetric Fluid Models

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Chinese Physics Letters 2012年第5期29卷 41-44页

作者： M.Sharif z.yousaf Department of Mathematics University of the PunjabQuaid-e-Azam CampusLahore-54590Pakistan

We attempt to discover some exact analytical models of the spherically symmetric spacetime of collapsing fluid under shearfree conditions.Two types of solution are considered:one is to impose a condition on the mass function,while the other is to restrict the pressure.We obtain five exact models in total,and some of them satisfy the Darmoie conditions.

关键词： conditions. exact satisfy

Electromagnetic effects on anisotropic expansion-free fluid content

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Communications in Theoretical Physics 2023年第10期75卷 79-89页

作者： z yousaf H Asad Bander Almutairi Adnan Malik Department of Mathematics University of the PunjabQuaid-i-Azam CampusLahore-54590Pakistan Department of Mathematics College of ScienceKing Saud UniversityP.O.Box 2455 Riyadh 11451Saudi Arabia School of Mathematical Sciences Zhejiang Normal UniversityJinhuaZhejiangChina

The major goal of this work is to find solutions of Einstein–Maxwell field equations for anisotropic,expansion-free,non-static,spherically distributed matter content.The analytical models that highlight the major benefit of simplicity are shown and this makes it possible to use them as a toy model to illustrate how cavities evolve.Furthermore,the transport equations,quasi-homologous constraints and the junction conditions are also evaluated along with their useful implications.Eventually,the consequences of electric force on this system are summed up in the last section.

关键词： gravitation neutron stars modified gravity hydrodynamics voids

Precipitation of multi-type nano-quasicrystals in a Mg-zn-Y alloy

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Journal of Magnesium and Alloys 2024年第3期12卷 997-1008页

作者： W.z.Wang X.z.zhou L.F.zhang H.Q.Ye z.Q.Yang Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of ScienceShenyang 110016China Ji Hua Laboratory Foshan 528251China Foshan University Foshan 528231China

Mg-6zn-1Y(at.%)ribbons with strengthening precipitates of multi-type nanoquasicrystals were prepared by melt-spinning followed by aging treatments.Microstructural evolution of the rapidly solidified ribbons during isothermal aging was comprehensively studied using various electron microscopy techniques.Two new kinds of decagonal quasicrystals were formed in aged ribbons,in addition to precipitation of nanometer icosahedral quasicrystals.Atomic-resolution observations reveal that both decagonal quasicrystals can be modeled by quasiperiodic tiling with decagonal clusters of 2.5 nm in diameter,but overlap of neighboring clusters in both decagonal quasicrystals is different from the Gummelt model observed in other quasicrystals.A shell composed of complex Laves Mg-zn domains was formed surrounding each decagonal quasicrystal precipitate upon prolonged aging.In addition,all kinds of nanoprecipitates exhibit excellent structure and size stability at 573 K.Our findings may have implications for not only fundamental studies about quasicrystals,but also microstructural manipulation of high-performance Mg alloys.

关键词： Quasicrystal Mg alloys Rapid solidification Scanning-transmission electron microscopy.

Esophageal inserted subclavian catheter:a rare complication

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World Journal of Emergency Medicine 2024年第3期15卷 243-245页

作者： DilberÜçöz Kocaşaban SertaçGüler Emergency Medicine Clinic Health Sciences University Ankara Training and Research HospitalAnkara 06930Turkey

Central venous catheterization(CVC) is an invasive procedure for administering fluids,nutrients,and drugs;monitoring central venous pressure;performing pulmonary artery catheterization;and placing transvenous pacemakers in intensive care units and all specialties,from anesthesia to emergency medicine,for the treatment of trauma and hemodynamically unstable pediatric and adult patients.[1,2]Complications have been observed in more than 15% of patients who underwent CVC.Mechanical,infectious,and thrombotic complications have been reported in 5%–19%,5%–26%,and 2%–26% of patients,respectively.[3] Malposition,on the other hand,is common in subclavian catheter insertion and is usually associated with an initially misplaced guidewire.[4]

关键词： unstable insertion initially

Dysregulation of RNA modification systems in clinical populations with neurocognitive disorders

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Neural Regeneration Research 2024年第6期19卷 1256-1261页

作者： Helen M.Knight Merve Demirbugen ?z Adriana PerezGrovas-Saltijeral Division of Cells Organisms and Molecular Genetics School of Life Sciences University of Notingham Department of Pharmaceutical Toxicology Faculty of Pharmacy Ankara University

The study of modified RNA known as epitranscriptomics has become increasingly relevant in our understanding of disease-modifying mechanisms. Methylation of N6 adenosine(m6A) and C5 cytosine(m5C) bases occur on mRNAs, tRNA, mt-tRNA, and rRNA species as well as non-coding RNAs. With emerging knowledge of RNA binding proteins that act as writer, reader, and eraser effector proteins, comes a new understanding of physiological processes controlled by these systems. Such processes when spatiotemporally disrupted within cellular nanodomains in highly specialized tissues such as the brain, give rise to different forms of disease. In this review, we discuss accumulating evidence that changes in the m6A and m5C methylation systems contribute to neurocognitive disorders. Early studies first identified mutations within FMR1 to cause intellectual disability Fragile X syndromes several years before FMR1 was identified as an m6A RNA reader protein. Subsequently, familial mutations within the m6A writer gene METTL5, m5C writer genes NSUN2, NSUN3, NSUN5, and NSUN6, as well as THOC2 and THOC6 that form a protein complex with the m5C reader protein ALYREF, were recognized to cause intellectual development disorders. Similarly, differences in expression of the m5C writer and reader effector proteins, NSUN6, NSUN7, and ALYREF in brain tissue are indicated in individuals with Alzheimer’s disease, individuals with a high neuropathological load or have suffered traumatic brain injury. Likewise, an abundance of m6A reader and anti-reader proteins are reported to change across brain regions in Lewy bodies diseases, Alzheimer’s disease, and individuals with high cognitive reserve. m6A-modified RNAs are also reported significantly more abundant in dementia with Lewy bodies brain tissue but significantly reduced in Parkinson’s disease tissue, whilst modified RNAs are misplaced within diseased cells, particularly where synapses are located. In parahippocampal brain tissue, m6A modification is enriched in transcripts associated with psychiatri

关键词： 5-methylcytosine methylation Alzheimer's disease cognitive diseases epitranscriptomics intellectual disability Lewy body diseases N6 adenosine RNA modification

Rational design of AgGaS/znS/znS quantum dots with a near-unity photoluminescence quantum yield via double shelling scheme

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Journal of Materials Science & Technology 2024年第2期169卷 235-242页

作者： H.X.Lu H.Liu z.z.Fu Y.Y.Chen H.Q.Dai z.Hu W.L.zhang R.Q.Guo Institute for Electric Light Sources School of Information Science and TechnologyFudan UniversityShanghai 200433China Institute of Future Lighting Academy for Engineering and TechnologyFudan UniversityShanghai 200433China Yiwu Research Institute of Fudan University YiwuZhejiang 322000China zhongshan-Fudan Joint Innovation Center Zhongshan 528437China

In this study,a two-step method was used to synthesize highly luminescent AgGaS/znS/znS quantum dots(QDs).In the first step,an inner znS shell was formed via a one-pot method,which resulted in a smaller lattice mismatch between the AgGaS core and the outer znS shell,thereby facilitating the formation of a thick outer shell.After the two-step shelling process,the synthesized AgGaS/znS/znS QDs showed an excellent photoluminescence quantum yield(PLQY)of 96.4%with a peak wavelength of 508 nm,repre-senting the highest PLQY reported thus far for AgGaS QDs.Furthermore,the effect of halogen ions in zn precursors on the shelling process was investigated.It was proposed that the capacity of halogen ions to coordinate with the QDs influenced the balance between zn cation diffusion and znS shelling reaction.Specifically,the znS shelling reaction was dominant when znCl_(2)was employed,while zn cation diffusion was the dominant process under the I^(−)-rich environment.This work provides insights into the interfacial restructuring during the znS shelling and offers a clear map for the tailored synthesis of core/shell QDs.

关键词： AgGaS Quantum dots Photoluminescence Core/shell Alloyed core/shell interface

Effects of multiple shapes for steady flow with transformer oil+Fe_(3)O_(4)+TiO_(2) between two stretchable rotating disks

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Applied Mathematics and Mechanics(English Edition) 2024年第2期45卷 373-388页

作者： M.RAHMAN M.TURKYILMAzOGLU z.MUSHTAQ Department of Mathematics Mirpur University of Science and TechnologyMirpur 10250Pakistan Department of Mathematics Hacettepe UniversityBeytepeAnkara 06532Turkiye

In this study,we examine the effects of various shapes of nanoparticles in a steady flow of hybrid nanofluids between two stretchable rotating disks.The steady flow of hybrid nanofluids with transformer oil as the base fluid and Fe_(3)O_(4)+TiO_(2)as the hybrid nanofluid is considered.Several shapes of Fe_(3)O_(4)+TiO_(2)hybrid nanofluids,including sphere,brick,blade,cylinder,and platelet,are studied.Every shape exists in the same volume of a nanoparticle.The leading equations(partial differential equations(PDEs))are transformed to the nonlinear ordinary differential equations(ODEs)with the help of similarity transformations.The system of equations takes the form of ODEs depending on the boundary conditions,whose solutions are computed numerically by the bvp4c MATLAB solver.The outputs are compared with the previous findings,and an intriguing pattern is discovered,such that the tangential velocity is increased for the rotation parameter,while it is decreased by the stretching values because of the lower disk.For the reaction rate parameter,the concentration boundary layer becomes shorter,and the activation energy component increases the rate at which mass transfers come to the higher disk but have the opposite effect on the bottom disk.The ranges of various parameters taken into account are Pr=6.2,Re=2,M=1.0,φ_(1)=φ_(2)=0.03,K=0.5,S=-0.1,Br=0.3,Sc=2.0,α_(1)=0.2,γ=0.1,E_(n)=2.0,and q=1.0,and the rotation factor K is within the range of 0 to 1.

关键词： transformer oil Brinkman number skin friction coefficient double rotating disk Nusselt number Sherwood number

Four Late-type Galaxies with Double Radio Lobes and Properties of Such Galaxies

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Research in Astronomy and Astrophysics 2024年第4期24卷 84-90页

作者： z.S.Yuan X.Y.Gao z.L.Wen J.L.Han National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China CAS Key Laboratory of FAST National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China School of Astronomy and Space Sciences University of Chinese Academy of SciencesBeijing 100049China

The triggering mechanism for radio lobes from late-type galaxies is not fully understood.More samples are desired for a thorough investigation and statistics.By utilizing the optical data from the newly released Dark Energy Spectroscopic Instrument imaging surveys and the radio sources from the NRAO VLA Sky Survey and the Faint Images of the Radio Sky at Twenty-centimeter,we identify four Late-type Galaxies with double Radio Lobes(La GRLs):J0217-3645,J0947+6220,J1412+3723 and J1736+5108.Including previously known La GRLs,we confirm the correlation between radio power P_(1.4GHz)and stellar mass M_(*)of host galaxies.Most(25/35)La GRLs belong to the blue cloud galaxies,while the newly identified cases in this work are located within the region of the red sequence.We find a clear correlation between the differential radio power,i.e.,the offset from the P_(1.4GHz)-M_(*)relation,and the galaxy color,indicating that bluer galaxies at a fixed M_(*)tend to host more powerful radio lobes.Furthermore,the majority(31/36)of La GRLs are either located in a galaxy group or displaying a disturbed morphology.We suggest that all of the galaxy mass,color and surrounding environment could play important roles in triggering radio lobes in late-type galaxies.

关键词： galaxies:active galaxies:jets galaxies:spiral radio continuum:galaxies