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Gauss-Bonnet and Lovelock Gravities and the Generalized Second Law of Thermodynamics

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Chinese Physics Letters 2009年第6期26卷 41-44页

作者： m. Akbar asghar Qadir Centre for advanced mathematics and Physics National University of Sciences and Technology Peshawar Road Rawalpindi Pakistan Kavli Institute for Theoretical Physics Chinese Academy of Sciences Beijing 100190

It has been shown [Chin. Phys. Lett.25 （2008） 4199] that the generalized second law of thermodynamics holds in Einstein gravity. Here we extend this procedure for Gauss-Bonnet and Lovelock gravities. It is shown that by employing the general expression for temperature Th =｜κ｜/2π= 1/2πτA （1-τA/2HτA） associated with the apparent horizon of a Friedman Robertson-Walker （FRW） universe and assuming Tm = bTh, we are able to construct conditions for which the generalized second law holds in Gauss Bonnet and Lovelock gravities, where Tm and Th are the temperatures of the source and the horizon respectively.

关键词： No English Keywords

Nonlinear dynamic modeling of planar moving Timoshenko beam considering non-rigid non-elastic axial effects

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Applied mathematics and mechanics(English Edition) 2024年第3期45卷 479-496页

作者： m.ABBASI GAVARI m.R.HOmAEINEZHad Faculty of mechanical Engineering K.N.Toosi University of TechnologyTehran 19991-43344Iran

Due to the importance of vibration effects on the functional accuracy of mechanical systems,this research aims to develop a precise model of a nonlinearly vibrating single-link mobile flexible *** manipulator consists of an elastic arm,a rotary motor,and a rigid carrier,and undergoes general in-plane rigid body motion along with elastic transverse *** accurately model the elastic behavior,Timoshenko’s beam theory is used to describe the flexible arm,which accounts for rotary inertia and shear deformation *** applying Newton’s second law,the nonlinear governing equations of motion for the manipulator are derived as a coupled system of ordinary differential equations(ODEs)and partial differential equations(PDEs).Then,the assumed mode method(Amm)is used to solve this nonlinear system of governing equations with appropriate shape *** assumed modes can be obtained after solving the characteristic equation of a Timoshenko beam with clamped boundary conditions at one end and an attached mass/inertia at the *** addition,the effect of the transverse vibration of the inextensible arm on its axial behavior is *** the axial rigidity,the effect makes the rigid body dynamics invalid for the axial behavior of the ***,numerical simulations are conducted to evaluate the performance of the developed model,and the results are compared with those obtained by the finite element *** comparison confirms the validity of the proposed dynamic model for the *** to the mentioned features,this model can be reliable for investigating the system’s vibrational behavior and implementing vibration control algorithms.

关键词： planar moving Timoshenko beam non-rigid non-elastic axial effect as-sumed mode method(Amm) nonlinear motion analysis

Free vibration and buckling analysis of polymeric composite beams reinforced by functionally graded bamboo fbers

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Applied mathematics and mechanics(English Edition) 2024年第3期45卷 543-562页

作者： H.m.FEIZABad m.H.YAS Department of mechanical Engineering Razi UniversityKermanshah ***Iran

Natural fibers have been extensively researched as reinforcement materials in polymers on account of their environmental and economic advantages in comparison with synthetic fibers in the recent *** fibers are renowned for their good mechanical properties,abundance,and short cycle *** beams are one of the fundamental structural components and are susceptible to mechanical loads in engineering applications,this paper performs a study on the free vibration and buckling responses of bamboo fiber reinforced composite(BFRC)beams on the elastic *** different functionally graded(FG)layouts and a uniform one are the considered distributions for unidirectional long bamboo fibers across the *** elastic properties of the composite are determined with the law of *** hamilton’s principle,the governing equations of motion are *** generalized differential quadrature method(GDQm)is then applied to the equations to obtain the *** achieved outcomes exhibit that the natural frequency and buckling load values vary as the fiber volume fractions and distributions,elastic foundation stiffness values,and boundary conditions(BCs)and slenderness ratio of the beam ***,a comparative study is conducted between the derived analysis outcomes for BFRC and homogenous polymer beams to examine the effectiveness of bamboo fibers as reinforcement materials,demonstrating the significant enhancements in both vibration and buckling responses,with the exception of natural frequencies for cantilever beams on the Pasternak foundation with the FG-◇fiber ***,the obtained analysis results of BFRC beams are also compared with those for carbon nanotube reinforced composite(CNTRC)beams found in the literature,indicating that the buckling loads and natural frequencies of BFRC beams are lower than those of CNTRC beams.

关键词： bamboo fiber free vibration buckling analysis functionally graded(FG)beam elastic foundation generalized differential quadrature method(GDQm)

住院患者认知障碍识别和信息管理的整合性综述

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International Journal of Nursing Sciences 2024年第1期11卷 120-132页

作者：熊蓓蓓 Daniel X.Bailey Paul Prudon Elaine m.Pascoe Leonard C.Gray Frederick Graham Amanda Henderson melinda martin-khan Centre for Health Services Research Faculty of MedicineThe University of QueenslandBrisbaneAustralia Centre for Clinical Research Faculty of MedicineThe University of QueenslandRoyal Brisbane&Women’s HospitalBrisbaneAustralia Dementia and Delirium Division of MedicinePrincess Alexandra HospitalBrisbaneAustralia School of Nursing Faculty of HealthQueensland University of TechnologyBrisbaneAustralia Nursing Practice Development Unit Princess Alexandra HospitalBrisbaneAustralia School of Nursing Midwifery and Social SciencesCentral Queensland UniversityBrisbaneAustralia Griffith Health Griffith UniversityBrisbaneAustralia School of Nursing Midwifery and ParamedicineThe University of the Sunshine CoastBrisbaneAustralia Department of Health and Life Sciences University of ExeterExeterUnited Kingdom School of Nursing University of Northern British ColumbiaPrince GeorgeCanada

目的旨在对目前提供急性照护的医院识别认知障碍患者以及在病历中记录和管理认知相关信息的实际情况及政策要求和推荐方法进行综述。方法采用Whittemore和Knaf1的五步法,系统检索medline,CINAHL和Scopus数据库,并检索了灰色文献来源。... 详细信息

目的旨在对目前提供急性照护的医院识别认知障碍患者以及在病历中记录和管理认知相关信息的实际情况及政策要求和推荐方法进行综述。方法采用Whittemore和Knaf1的五步法,系统检索medline,CINAHL和Scopus数据库,并检索了灰色文献来源。纳人了提供急性照护的医院已实施的患者认知障碍识别和认知信息管理相关的文献。采用混合方法评价工具和灰色文献质量评估清单对文章质量进行评价。采用主题分析法呈现和整合结果。该综述已在PROSPERO预注册(CRD42022343577)。结果共22篇原始研究文献和10篇政府/行业文件被纳人分析。结果显示,实践和政策之间存在差距。尽管在政策层面上高度重视认知障碍的识别、认知相关信息的透明度,以及与患者、家属和照顾者(如适用)之间的互动,但有时在临床实践中,认知评估是非正式的,患者的认知相关信息未作记录,与患者、家属和照顾者的互动也存在不足。结论.通过整合认知评估,利用信息技术开发信息管理综合系统,建立相关法律法规,提供教育与和培训,并采用国家层面的策略,有可能显著改善对认知障碍患者的识别和护理。

关键词：急性照护认知功能障碍数据透明度谵妄痴呆健康信息管理与患者互动.

Enhanced quantum resources via two distant atom-cavity systems under the influence of atomic dissipation

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Communications in Theoretical Physics 2024年第2期76卷 62-73页

作者： m Setodeh Kheirabady m K Tavassoly m Rafeie E Ghasemian Laser and Optics Group Faculty of PhysicsYazd UniversityYazd 89195-741Iran Department of Electrical Engineering Faculty of Intelligent Systems Engineering and Data SciencePersian Gulf UniversityBushehrIran

Quantum resources such as entanglement and coherence are the holy grail for modern quantum technologies. Although the unwanted environmental effects tackle quantum information processing tasks, suprisingly these key quantum resources may be protected and even enhanced by the implementation of some special hybrid open quantum systems. Here, we aim to show how a dissipative atom-cavity-system can be accomplished to generate enhanced quantum *** do so, we consider a couple of dissipative cavities, where each one contains two effective two-level atoms interacting with a single-mode cavity field. In practical applications, a classical laser field may be applied to drive each atomic subsystem. After driving the system, a Bell-state measurement is performed on the output of the system to quantify the entanglement and coherence. The obtained results reveal that the remote entanglement and coherence between the atoms existing inside the two distant cavities are not only enhanced, but can be stabilized, even under the action of dissipation. In contrast, the local entanglement between two atoms inside each dissipative cavity attenuates due to the presence of unwanted environmental ***, the local coherence may show the same behavior as the remote ***, the system provides the steady state entanglement in various interaction regimes,particularly in the strong atom-cavity coupling and with relatively large detuning. more interestingly, our numerical analyses demonstrate that the system may show a memory effect due to the fact that the death and revival of the entanglement take place during the interaction. Our proposed model may find potential applications for the implementation of long distance quantum networks. In particular, it facilitates the distribution of quantum resources between the nodes of large-scale quantum networks for secure communication.

关键词： remote entanglement and coherence atomic dissipation steady state entanglement Bell-statemeasurement

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 *** steady flow of hybrid nanofluids with transformer oil as the base fluid and Fe_(3)O_(4)+TiO_(2)as the hybrid nanofluid is *** shapes of Fe_(3)O_(4)+TiO_(2)hybrid nanofluids,including sphere,brick,blade,cylinder,and platelet,are *** shape exists in the same volume of a *** leading equations(partial differential equations(PDEs))are transformed to the nonlinear ordinary differential equations(ODEs)with the help of similarity *** system of equations takes the form of ODEs depending on the boundary conditions,whose solutions are computed numerically by the bvp4c mATLAB *** 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 *** 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 *** 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

Driving pressure in mechanical ventilation:A review

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World Journal of Critical Care medicine 2024年第1期13卷 15-27页

作者： Syeda Farheen Zaidi Asim Shaikh Daniyal Aziz khan Salim Surani Iqbal Ratnani Department of medicine Queen Mary UniversityLondon E14NSUnited Kingdom Department of medicine Aga Khan UniversitySindhKarachi 74500Pakistan Department of medicine Jinnah Postgraduate Medical CenterSindhKarachi 75510Pakistan Department of medicine and Pharmacology Texas A and M UniversityCollege StationTX 77843United States Department of Anesthesiology and Critical Care Houston Methodist HospitalHoustonTX 77030United States

Driving pressure(ΔP)is a core therapeutic component of mechanical ventilation(mV).Varying levels ofΔP have been employed during mV depending on the type of underlying pathology and severity of ***,ΔP levels have also been shown to closely impact hard endpoints such as *** this,conducting an in-depth review ofΔP as a unique,outcome-impacting therapeutic modality is extremely *** is a need to understand the subtleties involved in making sureΔP levels are optimized to enhance outcomes and minimize *** performed this narrative review to further explore the various uses ofΔP,the different parameters that can affect its use,and how outcomes vary in different patient populations at different pressure *** better utilizeΔP in mV-requiring patients,additional large-scale clinical studies are needed.

关键词： Driving pressure Acute respiratory distress syndrome mortality Positive end-expiratory pressure Ventilator induced lung injury mechanical ventilation

Facile synthesis of samarium and cerium doped double perovskite cobaltite with enhanced dielectric response

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Journal of Rare Earths 2024年第7期42卷 1317-1327,I0005页

作者： Yasir Abbas m.Kamran m.Anis-ur-Rehman Applied Thermal Physics Laboratory Department of PhysicsCOMSATS University IslamabadIslamabad 45550Pakistan

The investigation of Sm-Ce doping on structure,conduction,and dielectric response of Bi_(2)Ca_(2-2x)Sm_(x)CexCoO_(6)(x=0.000,0.025,0.050,0.075)(BCSCCO)are *** the specimens were synthesized by a facile synthesis technique named the co-precipitation route.X-ray diffraction(XRD)reveals that BCSCCO crystallizes into one phase with space group P21/*** crystallite size,dislocation density,lattice parameters,lattice strain,unit cell volume,and bulk density were determined using XRD *** structural properties of Bi_(2)Ca_(2)CoO_(6)were examined using calculations based on the density functional *** and experimental values discrepancy is less than 1%.A scanning electron microscope was used for performing a microstructural *** SEm images demonstrate the homogeneous distribution of grains with a range of sizes(0.054-0.090μm).The alternating current(ac)conductivity,dielectric permittivity,and tangent loss were also studied as a function of frequency(20 Hz-3 mHz)at different temperatures(100-500℃).All synthesized samples were examined using non-linear Debye's function to determine their spreading factor and relaxation *** specimen with the lowest crystallite size(∼23 nm)exhibits a high dielectric permittivity(∼3.80×10^(6)).The conduction mechanism was examined in the studied samples with the use of Jonscher's power *** power law indicates that the BCSCCO(x=0.000,0.025)follows correlated barrier hopping,whereas the x=0.050 and 0.075 compositions follow non-overlapping polaron *** studied specimen Bi_(2)Ca_(1.9)0Sm_(0.05)0Ce_(0.05)_(0)CoO_(6)with the highest density(∼5.65 g/cm^(3))displays a high electrical conductivity(∼46.1 S/cm).These findings correspond to those published for ceramics made from calcium cobaltite using solid-state reactions(5.0-26.0 S/cm).

关键词： Bismuth calcium samarium cerium cobaltite (BCSCCO) Spreading factor Conduction mechanism Rare earths

Braneworld black holes with modmax electrodynamics on the brane

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Communications in Theoretical Physics 2024年第6期76卷 120-128页

作者： Haryanto m Siahaan Jurusan Fisika Universitas Katolik ParahyanganJalan Ciumbuleuit 94Bandung 40141Indonesia

In this study,we investigate modmax electrodynamics localized within the Randall-Sundrum Ⅱ and Dvali-Gabadadze-Porrati branes,deriving corresponding 3-brane spacetime solutions that conform to the effective Einstein equations in each specific *** construct solutions for charged black holes within the effective Einstein equation framework in both braneworld *** examination explores the trajectories of charged objects in this spacetime,underscoring the significance of the nonlinear *** analysis uncovers the fact that,similar to the prior modmax black hole investigation,the nonlinear parameter plays a pivotal role in suppressing the effective charge of the black hole,due to its definite positive value.

关键词： RS-II DGP modmax brane