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Relationship between vegetation structure and microenvironment in Fagus grandifolia *** forest relicts in Mexico

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Journal of plant Ecology 2018年第2期11卷 237-247页

作者： Ernesto ChRodríguez-Ramírez Arturo Sánchez-González GregorioÁngeles-pérez Laboratorio de Biogeografía y Sistemática Facultad de CienciasUniversidad Nacional Autónoma de MéxicoCiudad de MéxicoMéxico Laboratorio de Ecología de poblaciones Centro de Investigaciones BiológicasUniversidad Autónoma del Estado de HidalgoCiudad UniversitariaCarretera Pachuca-Tulancingo Km.4.5Mineral de la Reforma 42184Hidalgo postgrado en Ciencias Forestales Colegio de PostgraduadosMontecillo 56230TexcocoEstado de MéxicoMéxico

Aims Changes in the structure and composition of forests,whether caused by natural or anthropic events,alter the microenviron-ment,sometimes *** the local environment has a direct impact on basic ecological processes,this has become a key component of *** beech forests(Fagus grandi-folia ***)in the Sierra Madre Oriental are restricted to sites with specific climate,soils and topography,making them an ideal natural system for ecological *** objectives of this study were to identify the relationship between the microen-vironment and the tree and shrub structure and composition of Mexican beech forests in the state of Hidalgo,and to compare the floristic similarity of these forests on the country scale using data from seven *** Specimens were collected for a period of one year at all locali-ties in the state of Hidalgo where beech forests are *** each locality,five 400 m2 plots were established,and structural attributes(basal area,coverage,density and species richness)and six environmental variables were measured in the *** relationship between structure and microenvironment was estimated by simple correlation and canonic correspondence analysis(CCA).in addition,floristic similarity between different beech forest localities in the Sierra Madre Oriental was esti-mated by correspondence analysis(CA).Important Findings Twenty tree species and eight shrub species were identified;at all localities studied *** *** dominated the *** multivariate analysis indicated that(i)in the four localities in the state of Hidalgo,all microenvironmental variables except pH are related to the variation observed in species composition and structure;(ii)the El Gosco locality had both tree and shrub species and microenvironmental factors different from those observed in the Fagus forests at the other localities in the study and(iii)the localities studied in order to draw country-scale compa

关键词： Canonical correspondence analysis fagus forest floristic composition Mexico montane cloud forest richness

Immunization with Cop-1 promotes neuroprotection and neurogenesis after ischemic stroke

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Neural Regeneration Research 2015年第11期10卷 1733-1734页

作者： yolanda Cruz paola Suárez-Meade Antonio Ibarra Facultad de Ciencias de la Salud Universidad Anáhuac México Norte Av.Universidad Anáhuac No.46 Col.Lomas Anáhuac C.P.52786 Huixquilucan Edo.de México proyecto CAMINA A.C. Tlalpan No.4430 Col.Toriello Guerra C.P.14050México City México

Cerebrovascular diseases are considered to be amongst the most serious public health issues,since they are the third leading cause of death（WHO,2014）and the most common cause of disability *** monetary significance is evidenced by the economic burden imposed on health care systems,given that the cost of medical care for a patient that has suffered a stroke is around$25,741US dollars every 5 years（Luengo-Fernandez et al.,2012）.A stroke occurs as a result of a disturbance or interruption of cerebral blood flow that significantly reduces the supply of oxygen and glucose to the neural tissue. Consequently, several cell death mechanisms （secondary lesion mechanisms） such as necrosis, excitotoxicity, free radical production and inflammation are triggered （Castillo, 2000）.

关键词： Immunization with Cop-1 promotes neuroprotection and neurogenesis after ischemic stroke BDNF Figure

Epistatic interactions between pterin and carotenoid genes modulate intra-morph color variation in a lizard

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Integrative Zoology 2022年第1期17卷 44-53页

作者： prem AGUILAR pedro ANDRADE Guillem pÉrez I DE LANUZA CIBIO/InBIO Centro de Investigação em Biodiversidade e Recursos Genéticos da Universidade do PortoPortoPortugal Ethology Lab Institut Cavanilles de Biodiversitat i Biologia EvolutivaUniversitat de ValènciaValènciaSpain

Color polymorphisms have become a major topic in evolutionary biology and substantial efforts have been devoted to the understanding of the mechanisms responsible for originating such colorful ***-morph continuous variation,on the other hand,has been neglected in most of the ***,we combine spectrophotometric/visual modeling and genetic data to study the mechanisms promoting continuous variation within categorical color morphs of podarcis *** results suggest that intra-morph variability in the pterin-based orange morph is greater compared to white and yellow *** also show that continuous variation within the orange morph is partially discriminable by *** results indicate that allelic variants at the BCO2 locus(responsible for deposition of yellow carotenoids)contribute to generate continuous variation in orange ***,other intrinsic and/or extrinsic mechanisms,such as body size,might be involved,opening a new avenue for future research on the drivers of continuous variation within-morphs.

关键词： BCO2 color polymorphism continuous variation lizard podarcis muralis

Coping with drought?Effects of extended drought conditions on soil invertebrate prey and diet selection by a fossorial amphisbaenian reptile

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Current Zoology 2023年第4期69卷 367-376页

作者： José Martín Jesús Ortega Roberto García-Roa Gonzalo Rodríguez-Ruiz Ana pérez-Cembranos Valentín pérez-Mellado Departamento de Ecología Evolutiva Museo Nacional de Ciencias NaturalesCSICMadridSpain Institute of Evolutionary Biology CSIC-Universitat Pompeu FabraBarcelonaSpain Ethology Lab Cavanilles Institute of Biodiversity and Evolutionary BiologyUniversity of ValenciaValenciaSpain Departamento de Biología Animal Universidad de SalamancaSalamancaSpain

Arid climates are characterized by a summer drought period to which animals seem ***,in some years,the drought can extend for unusually longer *** the effects of these current extreme weather events on biodiversity can help to understand the effects of climate change,as models predict an increase in drought ***,we examined the effects of“unusual”extended drought on soil invertebrate prey availability and on diet composition(based on fecal contents)and diet selection of a fossorial amphisbaenian,the checkerboard worm lizard Trogonophis *** data show interannual variations in summer drought *** abundance and diversity of soil invertebrates in spring were high,and similar to those found in a“normal”early autumn,after some rain had ended with the summer *** contrast,in years with“unusual”extended drought,abundance,and diversity of soil invertebrates in early autumn were very ***,there were seasonal changes in amphisbaenians’diet;in autumn with drought,prey diversity,and niche breadth decreased with respect to spring and autumns after some rain had *** did not eat prey at random in any season,but made some changes in prey selection that may result from drought-related restrictions in prey ***,in spite that amphisbaenians showed some feeding flexibility,their body condition was lower in autumn than in spring,and much lower in autumn with *** extended drought became the norm in the future,amphisbaenians might suffer important negative effects for their health state.

关键词： amphisbaenians drought feeding ecology soil invertebrates Trogonophis wiegmanni weather conditions

Algorithm for repairing the damaged images of grain structures obtained from the cellular automata and measurement of grain size

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International Journal of Minerals,Metallurgy and Materials 2012年第10期19卷 899-907页

作者： A.Ramírez-López M.A.Romero-Romo D.Muñoz-Negron S.López-Ramírez R.Escarela-pérez C.Duran-Valencia Department of Materials and Energy Metropolitan Autonomous UniversityMexico City 02200Mexico Department of Industrial Engineering Technological Autonomous Institute of MexicoMexico City 01080Mexico Department of Molecular Engineering Mexican Institute of PetroleumMexico City 07730Mexico

Computational models are developed to create grain structures using mathematical algorithms based on the chaos theory such as cellular automaton, geometrical models, fractals, and stochastic methods. Because of the chaotic nature of grain structures, some of the most popular routines are based on the Monte Carlo method, statistical distributions, and random walk methods, which can be easily programmed and included in nested loops. Nevertheless, grain structures are not well defined as the results of computational errors and numerical incon- sistencies on mathematical methods. Due to the finite definition of numbers or the numerical restrictions during the simulation of solidifica- tion, damaged images appear on the screen. These images must be repaired to obtain a good measurement of grain geometrical properties. Some mathematical algorithms were developed to repair, measure, and characterize grain structures obtained from cellular automata in the present work. An appropriate measurement of grain size and the corrected identification of interfaces and length are very important topics in materials science because they are the representation and validation of mathematical models with real samples. As a result, the developed al- gorithms are tested and proved to be appropriate and efficient to eliminate the errors and characterize the grain structures.

关键词： grain size and shape image restoration mathematical algorithms cellular automata solidification

Multitaper spectral method to estimate the elastic thickness of South China: Implications for intracontinental deformation

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Geoscience Frontiers 2014年第2期5卷 193-203页

作者： Yangfan Deng Zhongjie Zhang Weiming Fan Marta pérez-Gussinyé State Key Laboratory of Lithospheric Evolution Institute of Geology and Geophysics Chinese Academy of Sciences Guangzhou Institute of Geochemistry Chinese Academy of Science Department of Earth Sciences Royal Holloway University of London

The effective elastic thickness （Te） represents the thickness of the elastic layer or the flexural rigidity of the lithosphere, the equivalent of which can be calculated from the spectral analysis of gravity and topographic data. Studies of Te have profound influence on intracontinental deformation, and coupling of the tectonic blocks. In this paper, we use the multitaper spectral estimation method to calculate the coherence between Bouguer gravity and topography data, and to obtain the Te map of South China. Through the process of correction, we discuss the relationships of Te versus heat flow, and Te versus seismicity. The results show that Te distribution of South China is affected by three factors：the original age, which controls the basic feature;the Mesozoic evolution, which affects the Te distribution;and the neotectonic movement, which shaped the final distribution. The crust age has a positive correlation with the first-order Te distribution;thus the Yangtze Craton has a relatively higher Te （about 50 km） whereas the Te in Cathaysia block is only 10e20 km. By analysis and comparison among the tectonic models of South China, the Te distribution can be well explained using the flat-subduction model. As is typical with neotectonics, the region with a higher heat flow is related with a lower Te. The seismicity does not have a clear relationship with Te, but the strong seismicity could cause a low Te. Seismogenic layer （Ts） has a similar trend as Te in the craton, whereas in other areas the relationship is complex.

关键词： South China Effective elastic thickness Spectrum estimation Heat flow Seismicity

Automatic Fruit Morphology phenome and Genetic Analysis:An Application in the Octoploid Strawberry

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plant phenomics 2021年第1期3卷 167-180页

作者： Laura M.Zingaretti Amparo Monfort Miguel pérez-Enciso Centre for Research in Agricultural Genomics(CRAG) CSIC-IRTA-UAB-UB08193 BellaterraBarcelonaSpain Institut de Recerca i Tecnologia Agroalimentàries(IRTA) 08193 BarcelonaSpain ICREA Passeig de Lluís Companys 2308010 BarcelonaSpain

Automatizing phenotype measurement will decisively contribute to increase plant breeding *** phenotypes,morphological traits are relevant in many fruit breeding programs,as appearance influences consumer ***,these traits are manually or semiautomatically ***,fruit morphology evaluation can be enhanced using fully automatized procedures and digital images provide a cost-effective opportunity for this ***,we present an automatized pipeline for comprehensive phenomic and genetic analysis of morphology traits extracted from internal and external strawberry(Fragaria x ananassa)*** pipeline segments,classifies,and labels the images and extracts conformation features,including linear(area,perimeter,height,width,circularity,shape descriptor,ratio between height and width)and multivariate(Fourier elliptical components and Generalized procrustes)*** color patterns are obtained using an autoencoder to smooth out the *** addition,we develop a variational autoencoder to automatically detect the most likely number of underlying *** modeling is employed to estimate both additive and dominance effects for all *** expected,conformational traits are clearly ***,dominance variance is higher than the additive component for most of the ***,we show that fruit shape and color can be quickly and automatically evaluated and are moderately *** we study strawberry images,the algorithm can be applied to other fruits,as shown in the GitHub repository.

关键词： breeding additive dominance

Glial cells in the center of future ischemic stroke treatments

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Neural Regeneration Research 2022年第12期17卷 2659-2660页

作者： IvóH.Hernández Maria Josépérez-Álvarez Genomic Instability Group Spanish National Cancer Research Centre(CNIO)MadridSpain Departamento de Biología(Fisiología Animal)Facultad de Ciencias Universidad Autónoma de Madridand Instituto de Biología Molecular-CBMSOUAM/CSICMadridSpain

In the last century,increasing knowledge about glial cells has revealed their importance in brain physiology and disease and an exciting potential target for new therapeutic interventions(Hernández et al.,2021).Ischemic stroke is the most common of all types of *** the second leading cause of disability and mortality,ischemic stroke is a serious socio-economic burden *** it has been strongly associated with aging,during 2020 COVID-19 emerged as a new risk factor for ischemic stroke in younger patients(Cagnazzo et al.,2021).The only therapy or intervention currently available for humans is early reperfusion after the onset of the first ***,due to the high risk of brain hemorrhage,these treatments are suitable for only a small percentage of ***,reperfusion does not prevent post-injury neurodegeneration,hence the importance of finding new therapeutic alternatives to ameliorate ischemic damage and improve post-stroke quality of life.

关键词： mortality treatment younger

Speed Control of a DC Motor by Using Fuzzy Variable Structure Controller

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Speed Control of a DC Motor by Using Fuzzy Variable Structur...