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Temporal stability and directional change in a color cline of a marine snail from NW Spain

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Current Zoology 2024年第2期70卷 163-173页

作者： Juan Gefaell Ramon Vigo A.Honorato Gonzalez-Vazquez Juan Galindo emilio Rolan-Alvarez Centro de Investigacion Marina Universidade de VigoDepartamento de BioquimicaGenetica e Inmunologia36310 VigoSpain

The evolution and maintenance of color clines is a classic topic of research in evolutionary ***,studies analyzing the temporal dynamics of such clines are much less frequent,due to the difficulty of obtaining reliable data about past color distributions along environmen-tal *** this article,we describe a case of decades-long temporal stability and directional change in a color cline of the marine snail Littorina saxatilis along the coastal inlet of the Ria de Vigo(NW Spain).*** from this area shows a clear color cline with 3 distinct areas from the innermost to the more wave-exposed localities of the Ria:the inner,protected localities show an abundance of fawn-like individuals;the intermediate localities show a high diversity of colors;and the outer,wave-exposed localities show populations with a high frequency of a black and lineated *** compare data from the 1970s and 2022 in the same localities,showing that the cline has kept relatively stable for at least over half a century,except for some directional change and local variability in the frequency of certain *** regression analyses and biodiversity measures are presented to provide clues into the selective pressures that might be involved in the maintenance of this color *** research avenues to properly test the explanatory power of these selective agents as well as the possible origins of the cline are discussed.

关键词： clinal variation color polymorphism ecological gradient Littorina saxatilis natural selection wave exposure.

Floristic composition and edaphic relationships in ferruginous campo rupestre reference ecosystems

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Journal of Mountain Science 2024年第3期21卷 719-733页

作者： G.Wilson FeRNANdeS Letícia RAMOS Dario C.PAIVA Jéssica CUNHA-BLUM Vanessa Matos GOMeS Daniel NeGReIROS ecologia evolutiva&Biodiversidade Departamento de GenéticaEcologia e Evolução/ICBUniversidade Federal de Minas Gerais31270-901Belo HorizonteMGBrazil Knowledge Center for Biodiversity 31270-901Belo HorizonteMGBrazil department of Biological Sciences Institute of EnvironmentFlorida International UniversityMiamiFL 33199USA Programa de Pós Graduação em Biodiversidade e Uso dos Recursos Naturais Universidade Estadual de Montes ClarosMontes ClarosMGBrazil Laboratório de estudo das Relações Solo-Planta Departamento de SolosUniversidade Federal Rural do Rio de JaneiroSeropédicaRGBrazil

Land use change and occupation have led to modifications in the environment causing loss of biodiversity and ecosystem services throughout the *** environments with high economic relevance,such as the ferruginous campo rupestre(rupestrian grassland known as Canga in Brazil),are even more susceptible to severe impacts due to their extreme habitat conditions and low *** determination of reference ecosystems based on the intrinsic characteristics of the ecosystem is essential for conservation as well as to the implementation of ecological *** proposed the reference ecosystem of the three main types of habitats of the ferruginous campo rupestre based on their floristic *** described the floristic composition of each habitat and evaluated the physicochemical properties of the soils and the relationship between plants and *** three habitats showed high diversity of plant species and many endemic species,such as Chamaecrista choriophylla,Cuphea pseudovaccinium,Lychnophora pinaster,and Vellozia *** distribution of vegetation was strongly related with the edaphic characteristics,with a set of species more adapted to high concentration of base saturation,fine sand,organic carbon,and iron,while another set of species succeeded in more acidic soils with higher S and silt *** provide support for the contention that the ferruginous campo rupestre is a mosaic of different habitats shaped by intrinsic local *** to recognize the floristic composition of each particular habitat can lead to inappropriate restoration,increased habitat homogenization and increased loss of biodiversity and ecosystem *** study also advances the knowledge base for building the reference ecosystem for the different types of ferruginous campo rupestre habitats,as well as a key database for highlighting those species contribute most to community assembly in this diverse and threatened tropical mountain ecosystem.

关键词： Canga ecological restoration extreme ecosystem Non-forest ecosystems Rupestrian grassland Taxon environment relationships

Assessment of compressive strength of jet grouting by machine learning

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Journal of Rock Mechanics and Geotechnical engineering 2024年第1期16卷 102-111页

作者： esteban Diaz edgar Leonardo Salamanca-Medina Roberto Tomas departamento de Ingeniería Civil Escuela Politécnica SuperiorUniversidad de AlicanteP.O.Box 99E-03080AlicanteSpain

Jet grouting is one of the most popular soil improvement techniques,but its design usually involves great uncertainties that can lead to economic cost overruns in construction *** high dispersion in the properties of the improved material leads to designers assuming a conservative,arbitrary and unjustified strength,which is even sometimes subjected to the results of the test *** present paper presents an approach for prediction of the uniaxial compressive strength(UCS)of jet grouting columns based on the analysis of several machine learning algorithms on a database of 854 results mainly collected from different research *** selected machine learning model(extremely randomized trees)relates the soil type and various parameters of the technique to the value of the compressive *** the complex mechanism that surrounds the jet grouting process,evidenced by the high dispersion and low correlation of the variables studied,the trained model allows to optimally predict the values of compressive strength with a significant improvement with respect to the existing ***,this work proposes for the first time a reliable and easily applicable approach for estimation of the compressive strength of jet grouting columns.

关键词： Jet grouting Ground improvement Compressive strength Machine learning

Quasilinear elliptic problems with exponential growth via the Nehari manifold method: existence of nonnegative and nodal solutions

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Acta Mathematica Sinica,english Series 2024年

作者： Giovany FIGUeIReDO Sandra Moreira Ricardo Ruviaro Address departamento de Matematica Universidade de Brasilia departamento de Matematica e Informatica Universidade Estadual do Maranhao departamento de Matematica Universidade de Brasilia

In this paper we will be concerned with the problem -Δu-1/2Δ(a（x）u2)u+V（x）u=f（u）,x∈R2，where V is a potential continuous and f : R → R is a superlinear continuous function with exponential subcritical or exponential critical growth. We use as a main tool the Nehari manifold method in order to show existence of nonnegative solutions and existence of nodal solutions. Our results complement the classical result of solutions for quasilinear Schrodinger equations via the Nehari method due to Jia-quan Liu, Ya-qi Wang and Zhi-Qiang Wang in the sense that in this article we are considering nonlinearity of the exponential type.

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HVSR analysis of pumice sands for sediment depth characterization:A case study for Guadalajara,Mexico

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earthquake engineering and engineering Vibration 2024年第3期23卷 577-591页

作者： Hafid Salgado M. Alejandro Ramírez-Gaytan Adolfo Preciado Christian R.escudero departamento de Ciencias exactas Centro Universitario de la CostaUniversidad de GuadalajaraCP.48280 Puerto VallartaJaliscoMéxico departamento de Ciencias Computacionales Centro Universitario de Ciencias Exactas e IngenieríaUniversidad de GuadalajaraCP.44430 GuadalajaraJaliscoMéxico departamento del Hábitat y desarrollo Urbano Instituto Tecnológico y de Estudios Superiores de Occidente(ITESO)CP.45604 TlaquepaqueMéxico

The horizontal to vertical spectral ratio(HVSR)methodology is used here to characterize pumice soils and to image the three-dimensional surface geometry of Guadalajara,*** to other Latin American cities,Guadalajara is exposed to high seismic risk,with the particularity of being the largest urban settlement in Latin America built on pumice *** has not yet been tested to characterize subsoil depths in pumice *** to the questionable use of traditional geotechnical tests for the analysis of pumice soils,HVSR provides an alternative for its characterization without altering its fragile and porous *** this work,resonance frequency(F0)and peak amplitude(A0)are used to constrain the depth of the major impedance contrast that represents the interface between bedrock and pumice *** were compared with borehole depths and other available geotechnical and geophysical data and show good *** of the profiles estimated on the riverbanks that cross the city,reveals different subsoil thickness that could have an impact on different site responses on riverine areas to an eventual *** and academic efforts are combined in this work to characterize depth sediments,an important parameter that impacts the regulations for construction in the city.

关键词： subsoil of Guadalajara shallow soil thickness bedrock depth pumice soil characterization

Low-Cost and Biodegradable Thermoelectric devices Based on van der Waals Semiconductors on Paper Substrates

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energy & environmental Materials 2024年第1期7卷 201-206页

作者： Gulsum ersu Carmen Munuera Federico J.Mompean Daniel Vaquero Jorge Quereda João elias F.S.Rodrigues Jose A.Alonso eduardo Flores Jose R.Ares Isabel J.Ferrer Abdullah M.Al-enizi Ayman Nafady Sruthi Kuriakose Joshua O.Island Andres Castellanos-Gomez Materials Science Factory Instituto de Ciencia de Materiales de Madrid(ICMM-CSIC)Madrid E-28049Spain Nanotechnology Group USAL-NanolabUnivesidad de SalamancaSalamanca Junta de Castilla y León 37007Spain GISC Departamento de Física de MaterialesUniversidad Complutense de MadridMadrid E-28040Spain departamento de Física Aplicada Centro de Investigación y Estudios AvanzadosMérida 97310Mexico MIRe Group Departamento de Física de MaterialesUniversidad Autónoma de MadridMadrid E-28049Spain Instituto Nicolás Cabrera Universidad Autónoma de MadridMadrid E-28049Spain department of Chemistry College of ScienceKing Saud UniversityRiyadh 11451Saudi Arabia department of Physics and Astronomy University of Nevada Las VegasLas Vegas NV 89154USA

We present a method to fabricate handcrafted thermoelectric devices on standard office paper *** devices are based on thin films of WS_(2),Te,and BP(P-type semiconductors)and TiS_(3)and TiS_(2)(N-type semiconductors),deposited by simply rubbing powder of these materials against *** thermoelectric properties of these semiconducting films revealed maximum Seebeck coefficients of(+1.32±0.27)mV K^(-1)and(-0.82±0.15)mV K^(-1)for WS_(2)and TiS_(3),***,Peltier elements were fabricated by interconnecting the P-and N-type films with graphite electrodes.A thermopower value up to 6.11 mV K^(-1)was obtained when the Peltier element were constructed with three *** findings of this work show proof-of-concept devices to illustrate the potential application of semiconducting van der Waals materials in future thermoelectric power generation as well as temperature sensing for low-cost disposable electronic devices.

关键词： paper-based electronics Seebeck effect semiconductors thermoelectrics van der Waals materials

All-electron basis sets for H to Xe specific for ZORA calculations:Applications in atoms and molecules

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Chinese Physics B 2024年第8期33卷 238-246页

作者： C.S.Gomes F.e.Jorge A.Canal Neto departamento de Fisica Universidade Federal do Espirito Santo29075-910 VitoriaESBrazil departamento de Fisica Instituto de Ciencias Exatas e BiologicasUniversidade Federal de Ouro Preto Campus Universitario Morro do Cruzeiro35402-136 Ouro PretoMGBrazil

A segmented basis set of quadruple zeta valence quality plus polarization functions(QZP)for H through Xe was developed to be used in conjunction with the ZORA *** set was augmented with diffuse functions to describe electrons farther away from the nuclei *** the ZORA-CCSD(T)/QZP-ZORA theoretical model,atomic ionization energies and bond lengths,harmonic vibrational frequencies,and atomization energies of some molecules were *** addition of core-valence corrections has been shown to improve the agreement between theoretical and experimental results for molecular *** atomization energies,a similar observation emerges when considering spin-orbit *** the augmented QZP-ZORA set,static mean dipole polarizabilities of a set of atoms were calculated and compared with previously published recommended and experimental *** evaluations of the ZORA and Douglas–Kroll–Hess Hamiltonians were made for each property studied.

关键词： QZP-ZORA and AQZP-ZORA basis sets elements from H to Xe CCSD(T)method atomic and molecular properties

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

Towards efficient strain engineering of 2D materials:A four-points bending approach for compressive strain

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Nano Research 2024年第6期17卷 5317-5325页

作者： Hao Li Félix Carrascoso Ana Borrás Gloria P.Moreno Francisco J.Aparicio Ángel Barranco Andrés Castellanos Gómez Campus de Cantoblanco Instituto de Ciencia de Materiales de MadridC.Sor Juana Inés de la Cruz328049 MadridSpain Nanotechnology on Surfaces and Plasma Lab Instituto de Ciencia de Materiales de Sevilla(CSIC-Universidad de Sevilla).C/Americo Vespucio 49E-41092 SevilleSpain departamento de Física Aplicada I Escuela Politécnica SuperiorUniversidad de Sevillac/Virgen deÁfrica 7E-41011 SevilleSpain

Strain engineering,as a powerful strategy to tune the optical and electrical properties of two-dimensional(2D)materials by deforming their crystal lattice,has attracted significant interest in recent years.2D materials can sustain ultra-high strains,even up to 10%,due to the lack of dangling bonds on their surface,making them ideal brittle *** remarkable mechanical resilience,together with a strong strain-tunable band structure,endows 2D materials with a broad optical and electrical response upon ***,strain engineering based on 2D materials is restricted by their nanoscale and strain quantification *** this study,we have modified a homebuilt three-points bending apparatus to transform it into a four-points bending apparatus that allows for the application of both compressive and tensile strains on 2D *** approach allows for the efficient and reproducible construction of a strain system and minimizes the buckling effect caused by the van der Waals interaction by adamantane encapsulation *** results demonstrate the feasibility of introducing compressive strain on 2D materials and the potential for tuning their optical and physical properties through this approach.

关键词： uniaxial compressive strain polymer encapsulation differential reflectance spectroscopy exciton tunability