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Neural regeneration research 2024年第4期19卷 788-799页

作者： r.Scott Duncan Sean m.riordan matthew c.Gernon Peter Koulen Department of Ophthalmology School of MedicineUniversity of Missouri Department of Biomedical Sciences School of MedicineUniversity of Missouri

cannabinoids are lipophilic substances derived from cannabis sativa that can exert a variety of effects in the human *** have been studied in cellular and animal models as well as in human clinical trials for their therapeutic benefits in several human *** of these include central nervous system(cNS)diseases and dysfunctions such as forms of epilepsy,multiple sclerosis,Parkinson’s disease,pain and neuropsychiatric *** addition,the endogenously produced cannabinoid lipids,endocannabinoids,are critical for normal cNS function,and if controlled or modified,may represent an additional therapeutic avenue for cNS *** review discusses in vitro cellular,ex vivo tissue and in vivo animal model studies on cannabinoids and their utility as therapeutics in multiple cNS *** addition,the review provides an overview on the use of cannabinoids in human clinical trials for a variety of cNS *** and endocannabinoids hold promise for use as disease modifiers and therapeutic agents for the prevention or treatment of neurodegenerative diseases and neurological disorders.

关键词： anandamide cannabidiol cannabinoid endocannabinoid epilepsy multiple sclerosis neurodegeneration neuroprotection tetrahydrocannabinol

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

Pile foundation in alternate layered liquefiable and non-liquefiable soil deposits subjected to earthquake loading

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Earthquake Engineering and Engineering Vibration 2024年第2期23卷 359-376页

作者： Praveen Huded m Suresh r Dash LEA Associates South East Asia Pvt.Ltd. New Delhi 110044India Indian Institute of Technology Bhubaneswar Khurda 752050India

Pile foundations are still the preferred foundation system for high-rise structures in earthquake-prone *** foundations have experienced failures in past earthquakes due to *** on pile foundations in liquefiable soils has primarily focused on the pile foundation behavior in two or three-layered soil ***,in natural occurrence,it may occur in alternative layers of liquefiable and non-liquefiable ***,the experimental and/or numerical studies on the layered effect on pile foundations have not been widely addressed in the *** of the design codes across the world do not explicitly mention the effect of sandwiched non-liquefiable soil layers on the pile *** the present study,the behavior of an end-bearing pile in layered liquefiable and non-liquefiable soil deposit is studied *** study found that the kinematic bending moment is higher and governs the design when the effect of the sandwiched non-liquefied layer is considered in the analysis as opposed to when its effect is ***,ignoring the effect of the sandwiched non-liquefied layer in a liquefiable soil deposit might be a nonconservative design approach.

关键词： pile foundation liquefaction alternately layered soil fixity effect layered effect

Kinematic analysis of flexible bipedal robotic systems

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Applied mathematics and mechanics(English Edition) 2024年第5期45卷 795-818页

作者： r.FAZEL A.m.SHAFEI S.r.NEKOO Department of mechanical Engineering Shahid Bahonar University of KermanKerman ***Iran Departamento de Ingenieria de Sistemas y Automatica Escuela Técnica Superior de IngenieriaUniversidad de SevillaSeville 41092Spain

In spite of its intrinsic complexities,the passive gait of bipedal robots on a sloping ramp is a subject of interest for numerous *** distinguishes the present research from similar works is the consideration of flexibility in the constituent links of this type of robotic *** is not a far-fetched assumption because in the transient(impact)phase,due to the impulsive forces which are applied to the system,the likelihood of exciting the vibration modes increases ***,the human leg bones that are involved in walking are supported by viscoelastic muscles and ***,for achieving more exact results,it is essential to model the robot links with viscoelastic *** this end,the Gibbs-Appell formulation and Newton's kinematic impact law are used to derive the most general form of the system's dynamic equations in the swing and transient phases of *** most important issue in the passive walking motion of bipedal robots is the determination of the initial robot configuration with which the system could accomplish a periodic and stable gait solely under the effect of gravitational *** extremely unstable nature of the system studied in this paper and the vibrations caused by the impulsive forces induced by the impact of robot feet with the inclined surface are some of the very serious challenges encountered for achieving the above-mentioned *** overcome such challenges,an innovative method that uses a combination of the linearized equations of motion in the swing phase and the algebraic motion equations in the transition phase is presented in this paper to obtain an eigenvalue *** solving this problem,the suitable initial conditions that are necessary for the passive gait of this bipedal robot on a sloping surface are *** effects of the characteristic parameters of elastic links including the modulus of elasticity and the Kelvin-Voigt coefficient on the walking stability of this type of

关键词： bipedal robot flexible link swing phase transient phase eigenvalue problem Kelvin-Voigt coefficient

cr-induced fusion reactions to synthesize superheavy elements

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Nuclear Science and Techniques 2024年第5期35卷 122-130页

作者： S.madhu H.c.manjunatha N.Sowmya B.m.rajesh L.Seenappa r.S.Susheela Department of Physics R V College of EngineeringBangalore 560074India Visvesvaraya Technological University BelagaviKarnataka 590018India Department of Physics Government First Grade CollegeSrinivasapurKarnataka 563135India Department of Physics Government First Grade CollegeDevanahallyKarnataka 562110India Department of Physics Government First Grade CollegeMulbagalKarnataka 563131India Department of Physics Government First Grade collegeNanjangudOoty RoadMysore 571301India

We investigated ^(50,52-54)cr-induced fusion reactions for the synthesis of the superheavy element in the 104≤Z≤122 *** cross sections produced in this investigation using ^(54)cr projectiles were compared with those obtained in prior *** estimated cross sections from this analysis are consistent with the findings of prior *** the current study,the predicted cross section was found to be 42fb at 236 meV for ^(53)cr+^(243)Am,23.2 fb at 236 meV for ^(54)cr+^(247)cm,95.6 fb at 240 meV for ^(53)cr+248Bk,and 1.33 fb at 242 meV for ^(53)cr+***,these projected cross sections with excitation energy and beam energy will be useful in future cr-induced fusion reaction investigations.

关键词： Fusion cross sections compound nucleus formation probability Survival probability Evaporation residue cross sections

control system design for a pressure-tube-type supercritical water-cooled nuclear reactor via a higher order sliding mode method

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Nuclear Science and Techniques 2024年第1期35卷 145-154页

作者： m.Hajipour G.r.Ansarifar Department of Nuclear Engineering Faculty of PhysicsUniversity of IsfahanIsfahan 81746-73441Iran

Nuclear power plants exhibit non-linear and time-variable ***,designing a control system that sets the reactor power and forces it to follow the desired load is complicated.A supercritical water reactor(ScWr)is a fourth-generation conceptual *** an ScWr,the non-linear dynamics of the reactor require a controller capable of control-ling the *** this study,a pressure-tube-type ScWr was controlled during reactor power maneuvering with a higher order sliding mode,and the reactor outgoing steam temperature and pressure were controlled *** an ScWr,the temperature,pressure,and power must be maintained at a setpoint(desired value)during power *** point kinetics equations with three groups of delayed neutrons were used in the ***-order and classic sliding mode controllers were separately manufactured to control the plant and were compared with the PI controllers speci-fied in previous *** controlled parameters were reactor power,steam temperature,and ***,for these parameters,the PI controller had certain instabilities in the presence of *** classic sliding mode controller had a higher accuracy and stability;however its main drawback was the chattering *** was highly accurate and stable and had a small computational *** reality,it followed the desired values without oscillations and chattering.

关键词： Supercritical water nuclear reactor Higher order sliding mode controller Steam temperature Steam pressure Point kinetics model

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巴西油气勘探开发历程:从陆上到超深水

石油勘探与开发 2024年第4期51卷 796-806页

作者： ANJOS Sylvia m c SOmBrA cristiano L SPADINI Adali r 巴西国家石油公司里约热内卢20231-030巴西

21世纪以来,随着桑托斯盆地深水盐下获得一系列重大油气发现,巴西东部海域成为全球深水油气勘探与生产的热点区域。通过全面回顾巴西油气勘探开发历程,系统阐述了从陆上到海域、从浅水到深水—超深水直至盐下勘探的探索实践、战略转变... 详细信息

21世纪以来,随着桑托斯盆地深水盐下获得一系列重大油气发现,巴西东部海域成为全球深水油气勘探与生产的热点区域。通过全面回顾巴西油气勘探开发历程,系统阐述了从陆上到海域、从浅水到深水—超深水直至盐下勘探的探索实践、战略转变、重大突破和关键理论技术。巴西国家石油公司(简称巴西国油)自1953年成立以后的15年间,在陆上古生界克拉通盆地和断陷盆地进行了勘探,并于断块和三角洲砂体圈闭获得了一些中小型油气发现。20世纪70年代,应用重力流沉积模式和高质量三维地震等勘探新技术,在坎波斯盆地浅水中发现Namorado和Enchova等油田,随后深水盐上勘探获得突破,成功发现marlim、roncador等大型油田。21世纪初,通过盐下含油气系统、碳酸盐岩成储成藏模式和核磁共振测井等理论技术攻关,推动桑托斯盆地下白垩统湖相碳酸盐岩陆续获得Tupi(Lula)、Buzios、mero等世界级超深水盐下大油田的系列重大发现。在复杂的深水作业环境下,油气开发工程面临巨大挑战,巴西国油通过启动深水研发计划(PrOcAP),开发并实施窄压力窗口控压钻井、加压钻井液帽钻井、多段智能完井、水下采油及浮式生产平台开发和流动保障等关键技术,显著提升了钻完井、油气田开发和输运的效率及安全性。此外,在浮式采储卸油系统建产规模受限的情况下,推进全球最大规模的cO_(2)捕集、驱油利用与埋存工程(ccUS-EOr),有效减少温室气体排放并提高了原油采收率。上述理论技术的发展和应用,也为全球深水油气勘探开发提供了宝贵经验。未来巴西油气勘探将继续聚焦深水盐下碳酸盐岩和盐上浊积岩,并在古生界天然气等勘探领域持续寻求新的发现,同时通过技术创新和战略合作,促进巴西石油天然气行业的可持续发展。

关键词：巴西深水盐下勘探坎波斯盆地桑托斯盆地浊积岩湖相碳酸盐岩深水开发流动保障

Parametric investigation on the novel and cost-effective nano fly ash impregnated geopolymer system for sustainable construction

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Frontiers of Structural and civil Engineering 2024年第2期18卷 170-183页

作者： r.mOHANA S.m.Leela BHArATHI Department of civil Engineering Mepco Schlenk Engineering CollegeSivakasi 626123India

The hazardous environmental effects of greenhouse gas emissions and climate change demand alternative sources for cementitious materials in the construction *** development of geopolymer structures provides a way of producing 100%cement-free *** this research work,a novel and simple way of deriving nano particles from waste fly ash particles is *** effect of adding the synthesized nano fly ash particles as a filler medium in geopolymer mortars was investigated by considering strength and durability *** optimization was done by using regression analysis on the geopolymer mortar and the impact of adding nano fly ash particles was studied by varying different percentages of addition ranging from 0 to 7.5%by weight of binder *** the results,it was observed that 1%nano fly ash acted not only as a filler but also as nano-sized precursors of the polymerization process,resulting in denser geopolymer *** can explain the extraordinary gain in strength of 72.11 mPa as well as the denser core with negligible level of chloride ion penetration,making the material suitable for the development of structures susceptible to marine environment.

关键词： geopolymer nano fly ash chloride ion penetration durability polymerization fillers

consumer transparency in the production chain for plant varieties produced using new genomic techniques

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aBIOTEcH 2024年第2期5卷 239-246页

作者： J.m.Lukasiewicz c.c.m.van de Wiel L.A.P.Lotz m.J.m.Smulders Wageningen University&research P.O.Box 386NL-6700 AJ WageningenThe Netherlands

Plants edited with new genomic techniques(NGTs)currently fall under the Genetically modified Organisms Directive(2001/18/Ec)in the European *** the proposal of the European commission,NGT plants are partially exempted from the regulations of this *** proposal makes a distinction between two categories of NGT plants:NGT-1 and ***-1 category plants are considered equal to plants obtained through conventional breeding *** plants will not be labelled for the consumer,although they will be labelled as ***-2 category plants may be labelled with additional information as a positive *** of seeds of varieties made with gene editing,but not the products,would mean that most steps in the production chain are transparent,but not the last step towards ***“right to know”and increasing knowledge of gene-edited food is a common theme in food labelling towards ***,we describe current labelling regimes and registers and how these may be applied to provide transparency on gene-edited products to ***,we also look into consumer studies,which indicate a greater acceptance of gene-edited food among consumers,especially when additional benefits such as sustainability are mentioned.

关键词： Labelling New genomic techniques consumer transparency Plant products

Structural effects induced by dialysis-based purification of carbon nanomaterials

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Nano materials Science 2024年第4期6卷 475-483页

作者： A.D.Veloso A.m.Ferraria A.m.Botelho do rego A.S.Viana A.J.S.Fernandes A.J.Fielding r.A.Videira m.c.Oliveira cQ-Vr and chemistry Department University of Trás-os-Montes e Alto Douro BSIrG iBB-Institute for Bioengineering and BiosciencesDepartment of Chemical Engineeringand Associate Laboratory i4HB-Institute for Health and BioeconomyInstituto Superior TécnicoUniversidade de Lisboa centro de Química Estrutural Institute of Molecular SciencesDepartamento de Química e BioquímicaFaculdade de CiênciasUniversidade de Lisboa I3N and Physics Department University of AveiroCampus de Santiago Faculty of Science Pharmacy and Biomolecular SchoolLiverpool John Moores University rEQUImTE/LAQV Laborat orio de FarmacognosiaDepartamento de QuímicaFaculdade de Farm aciaUniversidade do Porto

Dialysis plays a crucial role in the purification of nanomaterials but its impact on the structural properties of carbon nanomaterials was never ***,a carbon-based nanomaterial generated electrochemically in potassium phosphate buffer,was characterized before and after dialysis against pure *** is shown that dialysis affects the size of the carbon domains,structural organization,surface functionalization,oxidation degree of carbon,and grade of ***,dialysis drives the nanomaterial organization from discrete roundish carbon domains,with sizes ranging from 70 to 160 nm,towards linear stacking structures of small nanoparticles （m）.In parallel,alcohol and ether （epoxide） surface groups evolve into more oxidized carbon groups （e.g.,ketone and ester groups）.Investigation of the as-prepared nanomaterial by electron paramagnetic resonance （EPr） revealed a resonance signal consistent with carbon-oxygen centred ***,this study brings to light the selective affinity of the carbon nanomaterial under study to capture Na+ions,a property greatly enhanced by the dialysis process,and its high ability to trap oxygen,particularly before *** findings open new perspectives for the application of carbon-based nanomaterials and raise awareness of the importance of structural changes that can occur during the purification of carbon-based nanomaterials.

关键词： Nanocarbon Surface functionalization Nmr XPS Hydrophilic carbon Paramagnetic