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Experimental Exclusion of Guanaco Grazing Increases Cover, Diversity, Land Function and Plant recruitment in Patagonia

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Phyton-International Journal of Experimental Botany 2024年第7期93卷 1383-1401页

作者： Carla Cepeda Gabriel oliva Daniela Ferrante INTA Instituto Nacional de Tecnología Agropecuaria Santa Cruz9400Rio GallegosArgentina Universidad Nacional de la Patagonia Austral Santa Cruz9400Rio GallegosArgentina

Semiarid Patagonia represents 25%of the rangeland area in Argentina,and sheep overgrazing has degraded about a third of it in the *** this century,depleted domestic stocks have mostly stabilized,but Guanaco populations have *** native camelids share habitat and diets with sheep,but their effect on vegetation is poorly understood and has long been *** set up an exclusion experiment in monte León and Cañadón Vaca,a semiarid shrubland grassland in southern Patagonia,currently grazed only by *** baselines were studied in 2016 in twelve plots,and half of them were protected from guanaco ***-six plots were cleared to study *** was reassessed in 2021,and changes were evaluated using a paired *** protected plots,vegetation cover increased,bare soil diminished,and vegetated patches grew in size,but the density of the patch-interpatch arrangement did not ***,measured by richness and the Shan-non-Wiener(SW)index,grew signiﬁ*** recycling increased,as did the Stability and Inﬁltration Land Function indexes,although these last differences were not signiﬁ*** cover under guanaco grazing also increased,mainly due to the growth of dwarf shrubs,a typical tendency in sheep grazing-induced transitions in the *** patches under grazing fragmented,resulting in smaller patches and denser patch struc-tures,while diversity and land function indexes remained *** plants established in cleared plots without guanacos showed higher cover density and individual *** effects are similar to those observed in numerous experimental sheep *** grazing may thus prevent restoration and contribute to the generalized land degradation processes that overgrazing has been causing in Patagonia for over a century.

关键词： rangelands herbivory biodiversity overgrazing carrying capacity fauna

New pharmacological tools:the use of diterpenes to promote adult hippocampal neurogenesis

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Neural regeneration research 2024年第8期19卷 1629-1630页

作者： ricardo Gomez-oliva Pedro Nunez-Abades Carmen Castro Department of Biomedicine Biotechnology and Public HealthDivision of PhysiologyUniversity of CadizCadizSpain Biomedical research and Innovation Institute of Cadiz(INiBICA) CadizSpain Department of Physiology University of SevilleSevilleSpain

Tissue regeneration maintains homeostasis and preserves the functional features of each ***,not all tissues show a strong repairing *** is the case of the central nervous *** is now well established that the generation of new functional neurons from stem cells in the adult brain occurs in specific regions of the brain of different species such as rodents,birds,primates,and humans(Eriksson et al.,1998).

关键词： capacity maintain preserve

Targeting epidermal growth factor receptor signaling to facilitate cortical injury repair?

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Neural regeneration research 2024年第5期19卷 935-936页

作者： ricardo Gómez-oliva Pedro Nunez-Abades Carmen Castro Área de Fisiología Facultad de Medicina Universidad de CádizCadizSpain Instituto de Investigación e Innovación en Biomedicina de Cádiz CadizSpain Departamento de Fisiología Facultad de FarmaciaUniversidad de SevillaSevilleSpain

The existence of neural stem cells(NSC)in specific areas of the adult mammalian brain leads to the generation of new neurons involved in homeostatic *** is the case of the NSC of the subventricular zone(SVZ)that produces olfactory bulb(OB)*** neurons integrate into circuits to modulate sensory information and participate in olfactory processing(Bragado Alonso et al.,2019).A series of hierarchical events need to take place to produce OB neurons from NSC of the ***,the activation of quiescent NSC is necessary to produce intermediate transit amplifying progenitors(TAP),which will generate *** latter are cells that maintain a proliferative phenotype while in an immature ***,once they initiate migration toward the OB,they progressively undergo their differentiation into neurons(Kjell et al.,2020).

关键词： ventricular maintain

Efficient removal of the recalcitrant metamizole contaminant from drinking water by using a CaLaCoO_(9) perovskite supported on recycled polyethylene

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Journal of Environmental Sciences 2024年第2期136卷 56-67页

作者： Ernesto Valadez-renteria Christian Perez-Carrasco Dulce Yolotzin medina-Velazquez Vicente rodriguez-Gonzalez Jorge oliva CONACYT-División de materiales Avanzados Instituto Potosino de Investigación Científica y Tecnológica A.C.San Luis PotosíSLP 78216México División de Ciencias Básicas e Ingeniería Universidad Autónoma Metropolitana AzcapotzalcoCol.Reynosa-TamaulipasC.P.MéxicoDF 02200México

metamizole(mZ)is a widely used anti-inflammatory *** to its common use,this contaminant is found in sewage and *** order to reduce the contamination produced by the mZ,we fabricated in this work a photocatalytic composite using recycled polyethylene(rPE)and the CaLaCoO_(9)(LCCO)*** nanoparticles had a microplate-like morphology and sizes of 1.4–5.5μm according to the analysis of *** photocatalytic properties of the LCCO powders were evaluated under ultraviolet-visible(UV-Vis)irradiation and found a removal efficiency of 96%.When the rPE+LCCO composite was employed for the photocatalytic degradation of mZ,a maximum degradation of 92.5%was *** influence of the pH on the photocatalytic activity was also studied and found that an initial pH=3 produced a total degradation of mZ after 240 min of UV-Vis ***,three reuse cycles were carried out for the pure LCCO powders and for the rPE+LCCO composites and found that the maximum loss of degradation was 5%.Furthermore,scavenger experiments demonstrated that the super oxide and hydroxyl radicals are formed during the photocatalytic reaction and were responsible for the degradation of ***,the X-ray photoelectron-spectroscopy and raman analysis demonstrated the formation of defects(oxygen vacancies),those ones delayed the electron-hole recombination,which in turn,enhanced the degradation of the ***,the studies performed in this work proved that composites made with recycled plastics and LCCO perovskites are a low-cost and feasible alternative for the cleaning of water sources polluted with pharmaceutical compounds.

关键词： Photocatalysis metamizole Pharmaceutical contaminant UV-Vis irradiation Perovskite

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

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

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