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Potential distribution of a montane rodent (Cricetidae, Handleyomys chapmani) through time in Mexico: the importance of occurrence data

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Journal of Mountain Science 2021年第8期18卷 2024-2033页

作者： cano Ivonne GUEVARA Lazaro Department of Zoology Institute of BiologyNational Autonomous University of Mexico04510Mexico CityMexico

Ecological Niche Modeling uses the geographic coordinates of species presence records as the primary input to estimate potential geographic *** is little known whether carrying out rigorous data pre-processing is necessary before building niche models to be transferred to different time *** we compared the current,past,and future potential distributions projected by niche models built from two different databases,an open-access database and a database compiled ad hoc,for Handleyomys chapmani,a rodent closely associated with montane cloud forests in *** models predicted different spatial patterns of climatic suitability for the three periods *** on our current knowledge of cloud forest species in Mexico,the distributions predicted by the model built from the ad hoc database are more ecologically realistic than those obtained from the open-access *** models built using the open-access database were particularly inaccurate at the limits of the geographic range,predicting larger,more diffuse distributions for the three *** conclude that pre-processing occurrence data is crucial for mountain species,as the number of localities and even minor inaccuracies in the geographic coordinates can translate into very different climatic conditions due to abrupt altitudinal ***,the predicted shifts in the potential distribution of *** over time indicate that this species is highly susceptible to climate change.

关键词： Cloud forests Ecological Niche Modeling Handleyomys chapmani Maxent Rodentia

PLANE WAVES NUMERICAL STABILITY OF SOME EXPLICIT EXPONENTIAL METHODS FOR CUBIC SCHRODINGER EQUATION

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Journal of Computational Mathematics 2016年第4期34卷 385-406页

作者： Begona cano Adolfo Gonzalez-Pachon Departamento de Matemdtica Aplicada Universidad de Valladolid IMUVA Paseo de Beldn 7 47011 VaUadolid Spain Departamento de Matemdtica Aplicada Universidad de Valladolid IMUVA Paseo de Beldn 7 47011 Valladolid Spain

Numerical stability when integrating plane waves of cubic SchrSdinger equation is thor- oughly analysed for some explicit exponential methods. We center on the following second- order methods： Strang splitting and Lawson method based on a one-parameter family of 2-stage 2nd-order explicit Runge-Kutta methods. Regions of stability are plotted and numerical results are shown which corroborate the theoretical results. Besides, a tech- nique is suggested to avoid the possible numerical instabilities which do not correspond to continuous ones.

关键词： Numerical stability Exponential splitting Lawson methods Projection ontoinvariant quantities Plane waves SchrSdinger equation.

Between plaza and peak: a montological perspective on verticality and urbanization in highland Peru

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Journal of Mountain Science 2023年第10期20卷 2783-2803页

作者： Andreas HALLER Domenico BRANCA Deyvis cano Institute for Interdisciplinary Mountain Research Austrian Academy of SciencesInnsbruck 6020Austria Department of Humanities and Social Sciences University of SassariSassari 07100Italy Programa Académico de Ingeniería Ambiental Universidad de HuánucoHudnuco 10001Peru

Under the influence of concentrated and extended urbanization,Andean cities and the different altitudinal zones of their“hinterlands”are experiencing profound changes in land cover—from the central plazas up to the highest *** complex regional-geographic characteristics of these socioecological systems,such as the vertical complementarity of land use,require a montological perspective on verticality and urbanization:it transcends disciplinary approaches and can be crucial to properly interpret the trajectories of land cover change and formulate hypotheses for future practiceoriented *** trajectories of land cover change characterized altitudinal zones of Andean cities and their surroundings over the last three decades?Are there similarities that allow for the formulation of more general hypotheses?Using the Peruvian cases of Cusco and Huaraz,and combining a traditional altitudinal zonation model of land use in Peru with direct field observations and GIS-based analyses of remotely sensed data from 1991,2001,2011,and 2021,this study identifies the main trajectories of land cover change in the Quechua(>2300–3500 m),Suni(>3500–4000 m),and Puna(>4000–4800 m)regions—and finds insightful similarities between Cusco and Huaraz:(1)an impressive area of built-up land substitutes grassland in the Quechua,which,following regional altitudinal zonation models,is characterized by irrigated and rain-fed cropland;(2)an unexpected expansion of irrigated cropland takes place in the Suni,which,in theory,often lacks irrigation infrastructure and is mostly used for rain-fed tuber cultivation;and(3)a clear change from“other land”to grassland occurs in the Puna—where grassland is thought to predominate,anyway,since pre-Hispanic *** that these changes reflect the interplay between speculative fallow,agricultural intensification,and ecological restoration,the results can be read as vertically complementary,local manifestations of concentrated and extended urba

关键词： Mountain cities Mountain agriculture Land use change Land cover change Rural-urban linkages Montology

Inconsistencies in four-dimensional Einstein-Gauss-Bonnet gravity

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Chinese Physics C 2021年第1期45卷 89-96页

作者： Julio Arrechea Adria Delhom Alejandro Jimenez-cano Instituto de Astrofisica de Andalucia(IAA-CSIC) Glorieta de la AstronomiaGranadaSpain Departamento de Fisica Teorica and IFIC Centro Mixto Universidad de Valencia-CSIC.Universidad de ValenciaBuijassot-46100ValenciaSpain Departamento de Fisica Teorica y del Cosmos and CAFPE Universidad de Granada18071 GranadaSpain

We attempt to clarify several aspects concemi ng the recently presented four-dimensional Ein stein-Gauss-Bonnet *** argue that the limiting procedure outlined in[***.124,081301(2020)]generally involves ill-defined terms in the four dimensional field *** ways to circumvent this issue are discussed,alongside remarks regarding specific solutions of the *** prove that,although linear perturbations are well behaved around maximally symmetric backgrounds,the equations for second-order perturbations are illdefined even around a Minkowskia n *** on ally,we perform a detailed analysis of the spherically symmetric solutions and find that the central curvature singularity can be reached within a finite proper time.

关键词： alternative theories of gravity singularities Einstein・Gauss-Bonnet

STABILITY AND RESONANCES OF MULTISTEP COSINE METHODS

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Journal of Computational Mathematics 2012年第5期30卷 517-532页

作者： B. cano M.J. Moreta Departamento de Matemdtica Aplicada IMUVA. Facultad de Ciencias. Paseo Belen 7 CP 47011 Valladolid Spain Departamento de Fundamentos del Andlisis Econdmico I. Universidad Complutense de Madrid. Campus de Somosaguas Pozuelo de Alarcdn 28223 Madrid Spain

In a previous paper, some particular multistep cosine methods were constructed which proved to be very efficient because of being able to integrate in a stable and explicit way linearly stiff problems of second-order in time. In the present paper, the conditions which guarantee stability for general methods of this type are given, as well as a thorough study of resonances and filtering for symmetric ones （which, in another paper, have been proved to behave very advantageously with respect to conservation of invariants in Hamiltonian wave equations）. What is given here is a systematic way to analyse and treat any of the methods of this type in the mentioned aspects.

关键词： Exponential integrators Multistep cosine methods Second-order partial dif-ferential equations Stability Resonances

Performance evaluation of Cuckoo filters as an enhancement tool for password cracking

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Cybersecurity 2024年第4期7卷 62-72页

作者： Maria-Dolores cano Antonio Vilfranca Igor Tasic Department of Information and Communication Technologies Universidad Politecnica de Cartagena30202 CartagenaSpain

Cyberthreats continue their expansion,becoming more and more complex and ***,credentials and passwords are still a critical point in *** cracking can be a powerful tool to fight against cyber criminals if used by cybersecurity professionals and red teams,for instance,to evaluate compliance with security policies or in forensic *** particular systems,one crucial step in the password-cracking process is comparison or matchmaking between password-guess hashes and real *** hypothesize that using newer data structures such as Cuckoo filters could optimize this *** results show that,with a proper configuration,this data structure is two orders of magnitude more efficient in terms of size/usage compared to other data structures while keeping a comparable performance in terms of time.

关键词： Authentication Passwords Password cracking Cybersecurity Cuckoo filters

Water-soluble hollow nanocrystals from self-assembly of AIEEactive Pt(II)metallomesogens

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Nano Research 2021年第1期14卷 245-254页

作者： Cristian Cuerva Javier Fernandez-Lodeiro Mercedes cano Jose Luis Capelo-Martinez Carlos Lodeiro BIOSCOPE Research Group LAQV@REQUIMTE Chemistry DepartmentNOVA School of Science and TechnologyNOVA University Lisbon2829-516 CaparicaPortugal PROTEOMASS Scientific Society Rua dos InventoresMadam ParqueCaparica Campus2829-516 CaparicaPortugal Department of Inorganic Chemistry Complutense University of MadridCiudad Universitaria28040 MadridSpain

Luminescent hollow micro-and nanocrystals have been successfully obtained taking advantage of the self-assembly behavior and the aggregation-induced emission enhancement properties of several bispyrazolate Pt(II)metallomesogens decorated with four terminal alkyl ***-in-water droplets have been used to confine the Pt(II)compounds and drive them to be self-assembled via intermolecular Pt…Pt interactions into spherical aggregates of about 200 or 50 *** of the oil phase generates highly-stable aqueous dispersions of nanocrystals that emit a bright orange light as a result of the existence of^(3)MMLCT excited *** methods and conditions have been tested for studying the effect of several parameters such as the temperature and the stirring speed in the final particle size and in the polydispersity ***,the micro-and nanocrystals are able to entrap hydrophobic drugs between the alkyl chains of the compounds,forming stable dispersions of drug-loaded capsules in *** droplet method is applied in the area of metallomesogens for the first time to synthesize self-assembled Pt(II)nanocapsules,which opens a new field of study that could allow the use of these liquid crystal materials in biomedical applications.

关键词： R(II)metallomesogens self-assembly luminescent nanomaterials droplets nanocapsules

Evaluating physical changes of iron oxide nanoparticles due to surface modification with oleic acid

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Chinese Physics B 2020年第10期29卷 186-194页

作者： S Rosales N Casillas A Topete O Cervantes G González J A Paz M E cano Centro Universitario de Ciencias Exactas e Ingenienas Universidad de GuadalajaraBlvd.Marcelino Garcia Burragan 1421C.P.44430GuadalajaraJaliscoMexico Centro Universitario de la Cienegu Universidad de GuadalajaraAv.Universidad 1115C.P.47820OcotlanJaliscoMexico Centro Universitario de Ciencias de In Salud Universidad de Guadalajara.Sierra Mojada 950C.P.44340GuadalajaraJaliscoMexico

The physical characterization of a colloidal system of superficially modified magnetic nanoparticles (MNPs) is presented. The system consists of oleic acid-coated iron oxide nanoparticles (OAMNP) suspended in water. A structural analysis is carried out by using standard physical techniques to determine the diameter and shape of the MNPs and also the width of the coating shell. The colloidal stability and the polydispersity index of this ferrofluid are determined by using Zeta potential measurements. Additionally, the magnetic characterization is conducted by obtaining the DC magnetization loops, and the blocking temperatures are determined according to the ZFC–FC protocol. Finally, the values of power absorption density P of the ferrofluid are estimated by using a magneto-calorimetric procedure in a wide range of magnetic field amplitude H and frequency f. The experimental results exhibit spherical-like shape of OAMNP with (20 ± 4) nm in diameter. Due to the use of coating process, the parameters of the magnetization loops and the blocking temperatures are significantly modified. Hence, while the uncoated MNPs show a blocking state of the magnetization, the OAMNP are superparamagnetic above room temperature (300 K). Furthermore, the reached dependence P versus f and P versus H of the ferrofluid with coated MNPs are clearly fitted to linear and quadratic correlations, respectively, showing their accordance with the linear response theory.

关键词： nanoparticles ferrofluid magnetic hyperthermia functionalization

An Intelligent Transportation System Application for Smartphones Based on Vehicle Position Advertising and Route Sharing in Vehicular Ad-Hoc Networks

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Journal of Computer Science & Technology 2018年第2期33卷 249-262页

作者： Seilendria A. Hadiwardoyo Subhadeep Patra Carlos T. Calafate Juan-Carlos cano Pietro Manzoni Deptartment of Computer Engineering Universitat Politecnica de Valencia Valencia 46022 Spain

Alerting drivers about incoming emergency vehicles and their routes can greatly improve their travel time in congested cities, while reducing the risk of accidents due to distractions. This paper contributes to this goal by proposing Messiah, an Android application capable of informing regular vehicles about incoming emergency vehicles like ambulances, police cars and fire brigades. This is made possible by creating a network of vehicles capable of directly communicating between them. The user can, therefore, take driving decisions in a timely manner by considering incoming alerts. Using the support of our GRCBox hardware, the application can rely on vehicular ad-hoc network communications in the 5 GHz band, being V2V （vehicle-to-vehicle） communication provided through a combination of Android-based smartphone and our GRCBox device. The application was tested in three different scenarios with different levels of obstruction, showing that it is capable of providing alerts up to 300 meters, and notifying vehicles within less than one second.

关键词： intelligent transportation systems (ITS) vehicular ad-hoc network (VANET) mobile application Android,navigation ad-hoc network