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AN OPTIMAL CONTROL PROBLEM FOR A LOTKA-VOLTERRA COMPETITION MODEL WITH CHEMO-REPULSION

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Acta Mathematica Scientia 2024年第2期44卷 721-751页

作者： Diana I.HERNÁNDEZ Diego A.rueda-GOMEZ Élder j.VILLAMIZAR-ROA Universidad Industrial de Santander Escuela de MatemáticasA.A.678BucaramangaColombia

In this paper we study a bilinear optimal control problem for a diffusive Lotka-Volterra competition model with chemo-repulsion in a bounded domain of ℝ^(ℕ),N=2,*** model describes the competition of two species in which one of them avoid encounters with rivals through a chemo-repulsion *** prove the existence and uniqueness of weak-strong solutions,and then we analyze the existence of a global optimal solution for a related bilinear optimal control problem,where the control is acting on the chemical ***,we derive first-order optimality conditions for local optimal solutions using the Lagrange multipliers ***,we propose a discrete approximation scheme of the optimality system based on the gradient method,which is validated with some computational experiments.

关键词： Lotka-Volterra chemo-repulsion optimal control optimality conditions

Opposed elevational variation in prevalence and intensity of endoparasites and their vectors in a lizard

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Current Zoology 2018年第2期64卷 197-204页

作者： Lola ALVAREZ-RUIZ Rodrigo MEGIA-PALMA Senda REGUERA Santiago Rulz Francisco j. ZAMORA-CAMACHO j.rdi FIGUEROLA Gregorio MORENO-rueda Centro de Investigaciones sobre Desertificacion-CSIC Ctra. Naquera Kin. 4.5 Moncada Valencia E-46113 Spain Departarnento de Ecologia Evolutiva Museo Nacional de Ciencias Naturales-CSIC c/Jose Gutierrez Abascal Madrid E-28006 Spain Unit of Ethology and Animal Welfare Faculty of Veterinary University CEU Cardenal Herrera Alfara del Patriarca (Valencia) E-46113 Spain Servicio de Control de Mosquitos DiputaciGn Provincial de Huelva Centro de InvestigaciGn Biornedica en Red Epidemiologia y Salud Publica (CIBERESP) Huelva Spain CIBER de Epidemiologia y Salud Peblica (CIBERESP) Spain Departamento de Biogeografia y Carnbio Global Museo Nacional de Ciencias Naturales-CSIC C/Jose Gutierrez Abascal 2 Madrid E-28006 Spain Departarnento de Ecologia de Hurnedales Estacion Biologica de Dofiana-CSIC c/Americo Vespucio s/n Sevilla E-41092 Spain Departamento de Zoologia Facultad de Ciencias Universidad de Granada Granada E-18071 Spain

Studying the causes of parasite geographic distribution is relevant to understand ecological and evolutionary processes that affect host populations as well as for species conservation. Temperature is one of the most important environmental variables affecting parasite distribution, as raising temperatures positively affect development, reproduction, and rate of transmission of both endo- and ectoparasites. In this context, it is generally accepted that, in mountains, parasite abundance decreases with elevation. However, empirical evidence on this topic is limited. In the present study, we analyzed the elevational variation of hemoparasites and ectoparasites of a lizard, Psammodromus algirus, along a 2,200-m elevational gradient in Sierra Nevada （SE Spain）. As pre- dicted, ectoparasite （mites, ticks, mosquitoes, and sandflies） abundance decreased with elevation. However, hemoparasite prevalence and intensity in the lizard augmented with altitude, showing a pattern contrary to their vectors （mites）. We suggest that tolerance to hemoparasites may increase with elevation as a consequence of lizards at high altitudes taking advantage of increased body condition and food availability, and reduced oxidative stress. Moreover, lizards could have been selected for higher resistance against hemoparasites at lowlands （where higher rates of replication are expected）, thus reducing hemoparasite prevalence and load. Our findings imply that, in a scen- ario of climate warming, populations of lizards at high elevation may face increased abundance of ectoparasites, accompanied with strong negative effects.

关键词： elevation immune system parasite distribution Psammodromus algirus reptile

Age structure of a lizard along an elevational gradient reveals nonlinear lifespan patterns with altitude

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Current Zoology 2020年第4期66卷 373-382页

作者： Mar Comas Senda Reguera Francisco j.amora-Camacho Gregorio Moreno-rueda Departamento de Zoologia Facultad de CienciasUniversidad de GranadaGranadaE-18071Spain Estacion Biologica de Donana(EBD-CSIC) Americo Vespucio 26SevillaE-41092Spain Department of Biological Sciences Dartmouth CollegeHanoverNHUSA

Lifespan is one of the main components of life *** lifespans can be expected in marginal ***,in the case of ectotherms,lifespan typically increases with altitude,even though temperature-one of the main factors to determine ectotherms'life history-declines with *** pattern can be explained by the fact that a shorter activity time favors *** this study,we analyzed how lifespan and other life-history traits of the lizard Psammodromus algirus vary along a 2,200 m elevational gradient in Sierra Nevada(SE Spain).Populations at inter-mediate altitudes(1,200-1,700 m),corresponding to the optimal habitat for this species,had the shortest lifespans,whereas populations inhabiting marginal habitats(at both low and at high altitudes)lived ***,this lizard did not follow the typical pattern of ectotherms,as it also lived longer at the lower limit of its distribution,nor did it show a longer lifespan in areas with optimal *** results might be explained by a complex combination of different gradients along the mountain,namely that activity time decreases with altitude whereas food availability *** could explain why lifespan was maximum at both high(limited activity time)and low(limited food availability)altitudes,resulting in similar lifespans in areas with contrasting environmental *** findings also indicated that reproductive investment and body condition increase with elevation,suggesting that alpine populations are locally adapted.

关键词： age structure elevation lite history longevity marginal habitats relative clutch mass

Morphological determinants of j.mping performance in the Iberian green frog

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Current Zoology 2020年第4期66卷 417-424页

作者： Gregorio Moreno-rueda Abelardo Requeinia-Blaimco Francisco j.Zamora-Camacho Mar Comas Guillem Pascual Departamento de Zoologia Facultad de CienciasUniversidad de GranadaGranadaE-18071Spain Department of Biological Sciences Dartmouth CollegeHanoverNH03055USA Galanthus/Ctra.de j.ia 46.17460 CelraSpain

Predation is one of the main selective forces in nature, frequently selecting potential prey for developing escape strategies. Escape ability is typically influenced by several morphological parameters, such as morphology of the locomotor appendices, muscular capacity, body mass, or fluctuating asymmetry, and may differ between sexes and age classes. In this study, we tested the relationship among these variables and j.mping performance in 712 Iberian green frogs Pelophylax perezi from an urban population. The results suggest that the main determinant of j.mping capacity was body size (explaining 48% of variance). Larger frogs j.mped farther, but j.mping performance reached an asymptote for the largest frogs. Once controlled by structural body size, the heaviest frogs j.mped shorter distances, suggesting a trade-off between fat storage and j.mping performance. Relative hind limb length also determined a small but significant percentage of variance (2.4%) in j.mping performance-that is, the longer the hind limbs, the greater the j.mping capacity. j.veniles had relatively shorter and less muscular hind limbs than adults (for a given body size), and their j.mping performance was poorer. In our study population, the hind limbs of the frogs were very symmetrical, and we found no effect of fluctuating asymmetry on j.mping performance. Therefore, our study provides evidence that j.mping performance in frogs is not only affected by body size, but also by body mass and hind limb length, and differ between age classes.

关键词： body mass fluctuating asymmetry hind limb length hind limb width locomotor performance morphometry

Prey availability, prey selection, and trophic niche width in the lizard Psammodromus algirus along an elevational gradient

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Current Zoology 2018年第5期64卷 603-613页

作者： Gregorio MORENO-rueda Elena MELERO Senda REGUERA Francisco j. ZAMORA-CAMACHO Ines ALVAREZ-BENITO Departamento de Zoologla Facultad de Ciencias Universidad de Granada Granada E-18071 Spain Departamento de Biogeografia y Carnbio Global Museo Nacional de Ciencias Naturales-CSIC C/Jose Gutierrez Abascal 2 E-28006 Madrid Spain

Mountains imply enormous environmental variation, with alpine habitats entailing harsh environ- ments, especially for ectotherms such as lizards. This environmental variability also may imply variation in prey availability. However, little is known about how lizard trophic ecology varies with elevation. In this study, we analyze diet, prey availability, prey selection, and trophic niche width in the lacertid lizard Psammodromus algirus along a 2,200-m elevational gradient in the Sierra Nevada （SE Spain）. The analysis of fecal samples has shown that Orthoptera, Formicidae, Hemiptera, Coleoptera, and Araneae are the main prey, although, according to their abundance in pitfall traps, Formicidae and Coleoptera are rej.cted by the lizard whereas Orthoptera, Hemiptera, and Araneae are preferred. Prey abundance and diversity increase with elevation and diet subtly varies along with the elevational gradient. The consumption of Coleoptera increases with elevation probably as a consequence of the lizard foraging more in open areas while basking. The electivity for Araneae increases with elevation. Araneae are rej.cted in the lowlands--where they are rela- tively abundant--whereas, at high elevation, this lizard positively selects them, despite they being less abundant. The lizard trophic niche width expands with elevation due to concomitant greater prey diversity and hence this lizard feeds on more prey types in highlands. Although no sex difference in diet has been found, the trophic niche is broader in females than males. As a whole, alpine lizards show a trophic niche simitar to that found at lower elevat（ons, suggesting that P. algirus is well adapted to the harsh environment found in alpine areas.

关键词： alpine habitats arthropods mountain ecology niche variation hypothesis trophic ecology

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

Annual variation of adult survival of a south-temperate House Wren population in Argentina

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Avian Research 2024年第2期15卷 229-237页

作者： Gustavo j.Fernandez Mariana E.Carro Paulo E.Llambías Grupo de Investigacion en Ecofisiología de Fauna Silvestre INIBIOMA-CONICETAsentamiento Universitario San Martín de los Andes(AUSMA)Universidad Nacional Del ComahuePasaje de la Paz 235(8370)San Martín de los AndesNeuquenArgentina Grupo de Investigacion de Biología de Aves IADIZA CCT-MendozaUniversidad Nacional de CuyoAvenida RuizLeal s/n Parque General San Martin5500MendozaArgentina

Identifying factors affecting the survival of individuals is essential for understanding the evolution of life-history traits and population *** numerous studies on this subj.ct in north-temperate environments,there is a lack of equivalent studies at similar latitudes in the ***,we used a 14-year dataset of capture,banding,and resighting to estimate the annual variation in the apparent adult survival probability of a south-temperate population of House Wrens(Troglodytes aedon bonariae).We evaluated temporal variation in sur-vival and the effect of environmental(climatic)and demographic variables(adult abundance,total number of fledglings produced during each breeding season)on survival *** found that the probability of adult survival decreased as the abundance of breeding adults *** density-dependent effect could be related to the resident lifestyle of southern House Wrens,which could determine an intense competition for territories and resources that ultimately would affect their survival.

关键词： Annual variation Cj. Density-dependence Survival Troglodytes aedon bonariae

Tree community composition,structure and diversity along an elevational gradient in an Andean forest of Northern Ecuador

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j.urnal of Mountain Science 2021年第9期18卷 2315-2327页

作者： j.MÉNEZ-paz Rosa WORTHY Samantha j.VALENCIA Renato PÉREZÁlvaro j.REYNOLDS Alex BARONE j.hn A BURGESS Kevin S Laboratorio de Ecología de Plantas Escuela de Ciencias BiológicasFacultad de Ciencias Exactas y NaturalesPontificia Universidad Católica del EcuadorQuito 17-01-2184Ecuador Department of Biology College of Letters&SciencesColumbus State UniversityColumbusGeorgia 31907USA Herbario QCA Escuela de Ciencias BiológicasFacultad de Ciencias Exactas y NaturalesPontificia Universidad Católica del EcuadorQuito 17-01-2184Ecuador The Lovett School AtlantaGeorgia 30327USA

The Andean forests of northern Ecuador are known for their high levels of plant diversity relative to the area they ***,these forests grow on steep slopes that lead to dramatic habitat gradients across short *** extreme habitat gradients make the Andean forest ecosystem an excellent natural laboratory for understanding the effect of elevation on forest community diversity,structure and *** established 31 plots(50 m×5 m)which are divided between two elevational transects in the cloud forest of the Siempre Verde Reserve in the western foothills of the Andes Mountains of northern *** trees and tree ferns with a diameter at breast height(dbh)≥5 cm were measured and *** examined changes in community composition,structure,and diversity along and between the elevational transects and three elevational zones:low(2437–2700 m),middle(2756–3052 m),and high(3163–3334 m).We found four main trends associated with the elevational gradients at this site:(1)community composition differed between the two transects and among the three elevational zones according to N-MDS,ANOSIM,and percentage of shared species,with some species having limited distributions,(2)metrics of community structure showed opposite relationships with elevation,depending on the transect,with the only significant relationship(negative)found between basal area and elevation in the open trail transect,(3)alpha diversity,in general,peaked at mid-elevations,and(4)beta diversity consistently increased with distance between plots along *** complexity of changes in community composition,structure,and alpha diversity along elevation may be related to the heterogeneity of the environment on a local scale,such as topography,soil composition,and even human impact,or to dispersal limitation and should be investigated *** changes in community composition and the relatively high beta diversity found at this site exemplify the biological complexity of mon

关键词： Elevational gradient Cloud forest Andes Structure Composition Diversity

Revolution and Restoration： The Revolution of Quito （Ecuador） Within the Independence Process of Latin America

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Sociology Study 2015年第2期5卷 146-156页

作者： j.an j. paz-y-Mino Cepeda Pontifical Catholic University of Ecuador Ecuador

The Revolution of Quito （1808-1812） in many aspects pioneered the way during the Latin American independence process. After the independence of Haiti （1804） and at its initial stage, the Sovereign j.nta in Quito, founded in 1809, took action together with the revolutionary movements of Chuquisaca and La paz. Controlled, its members persecuted and finally killed, the Revolution of Quito passed from a loyalty to an independence movement which resulted in the creation of the new State of Quito. The defeat of the Revolution of Quito restored the old regime. In the middle of this process, the threat of the Holy Alliance, which was born at the Congress of Vienna （1814-1815）, has particular significance for Quito and Latin America as it was the third attempt of a Spanish conquest The celebrations of the bicentenaries of the independence of Latin American countries have given a reason to value the concepts which the region developed during its anticolonial struggle, the first of its kind in the world and at the dawn of capitalism. G. W. F. Hegel always perceived Latin America as an ＂echo of a foreign Life＂. He never understood nor visited Latin America. He could not understand that another ＂spirit of the people＂ existed here which did not have a place in his elaborate universal history. And as has happened in the past, today Latin America is once again a pioneering region when it comes to setting the foundations for what should become its second independence, an idea which has been revived by the Latin American governments associated with the New Left.

关键词： Revolution of Quito Congress of Vienna independence of Latin America second independence spirit of the people