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Landform Instability and Land-use Dynamics in Tropical High Mountains, Central Mexico

Journal of Mountain Science 2012年第3期9卷 414-430页

作者： GARCíA-ROMERO arturo ACEVES-QUESADA José Fernando ARREDONDO-LEóN Carlos Departamento de Geografía Física Instituto de Geografía Universidad Nacional Autónoma de México. Circuito exterior s/n Ciudad Universitaria 04510 Mexico Distrito Federal Mexico Unidad Académica de Estudios Regionales de la Coordinación de Humanidades Universidad Nacional Autónoma de México

This investigation is an analysis of the influence of landform instability on the distribution of land-use dynamics in a hydrographical basin, located in the Mexican Volcanic Belt mountain range (central Mexico), currently affected by substantial changes in land use and deforestation. A landform map was produced, in addition to seven attribute maps - altimetry, drainage density, slope, relief energy, potential erosion, geology and tectonics - which were considered as factors for determining landform instability through Multi-criteria Evaluation Analysis. Likewise, the direction and rhythm of land-use dynamics were analyzed in four dates - between 1976 and 2000 - and cross tabulations were made between them, in order to analyze the trends and processes of land-use dynamics. Afterwards, the databases obtained were cross tabulated with the landform variables to derive areas, percentages and correlation indices. In the study area, high-instability landforms are associated with most ancient volcanic and sedimentary landforms, where high altitude, drainage density, slope and potential to develop gravitational and fluvial processes are the major factors favouring a land-use pattern, dominated by the conservation of extensive forest land, abandonment of human land use and regeneration of disturbed areas. In contrast, low-instability landforms correspond to alluvial plains and lava hills covered by pyroclasts, where low potential erosion to develop fluvial processes, added to water and soil availability and accessibility, have favoured a land-use pattern dominated by the expansion of agroforestry plantations and human settlements, showing a marked trend towards either intensification or permanence of the current land use and with little abandonment and regeneration.

关键词： Landform instability Multi-criteriaEvaluation Analysis Land-use change and processes Tuxpan River Basin

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Environmental Factors that Affect Primary Plant Succession Trajectories on Lahars(Popocatépetl Volcano,Mexico)

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Journal of Mountain Science 2015年第5期12卷 1254-1266页

作者： GARCIA-ROMERO arturo ALANIS-ANAYA Rocío Marisol MUNOZ-JIMENEZ Julio Departamento de Geografía Física Instituto de GeografíaUniversidad Nacional Autónoma de México.Circuitoexterior s/nCiudad Universitaria04510 MexicoDistrito FederalMexico Laboratorio de Análisis Geoespacial Instituto de GeografíaUniversidad Nacional Autónoma de México.Circuitoexterior s/nCiudad Universitaria04510 MexicoDistrito FederalMexico Departamento de A.G.R.y Geografía Física Facultad de Geografía e HistoriaUniversidad Complutense de Madrid.Calle Profesor Aranguren s/nCiudad Universitaria28040MadridSpain

The earliest stages of plant succession on severely disturbed sites usually follow highly unpredictable trajectories. However, in the Popocatépetl volcano area(50 km SE of Mexico City),the development of physiognomically distinct primary plant communities suggests the occurrence of various successional trajectories only 10 years after the onset of colonization of a temperate forest on lahars. To characterize plant communities and determine the environmental factors that drive the differences observed between plant communities and their successional trajectories, we monitored 64 circular sample plots(3.14 m2) from 2002 to 2011. We examined the plant communities' composition and structure in terms of their species richness and abundance, plant cover, and maximum stem height,and recorded 13 environmental factors related to the volcanic deposit characteristics, microclimate, soil,flow dynamics and gravitational processes. A cluster analysis of the species abundance data showed that,by 2011, six plant community types(CT's) had established, including grasslands, and open, dense and very dense shrub lands. As these communities developed over the same period of time and within the same overall ecosystem, then these plant community types were interpreted as different stages of the same successional trajectory. Two sequential main stages that drive regeneration were identified from this successional trajectory: a) the first four years are characterized by a steady increase in species richness and physiognomic development(plant size and coverage), mostly dominated by Baccharis conferta, Eupatorium glabratum and Senecio barbajohannis; b) from the sixth year onwards, a continued increase in the abundance of those same species led to the development of the dense shrubland *** in the availability of soil resources and disturbances linked to recent lahar flows were the main factors accounting for such differences.

关键词： Ecosystem regeneration Plantcolonization Primary succession Temperate forest Light exposure Elevation Soil Slope aspect

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Biogeographic patterns of the myxomycete biota of the Americas using a parsimony analysis of endemicity

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Fungal Diversity 2013年第2期59卷 159-177页

作者： arturo Estrada-Torres Diana Wrigley de Basanta Carlos Lado Centro de Investigación en Ciencias Biológicas Universidad Autónoma de TlaxcalaApartado Postal 183Tlaxcala 90000 TlaxcalaMexico Real Jardín Botánico de Madrid CSIC Plaza de Murillo 228014MadridSpain

Myxomycetes are microorganisms frequently considered to be of cosmopolitan distribution,however as studies in unexplored areas have intensified,more information has become available on the patterns of distribution of these organisms,but no historical or cladistic biogeographic approaches have been applied to understand such *** this study a parsimony analysis of endemicity(PAE)was used in order to generate a preliminary hypothesis on the biogeographic relationships of 13 American areas in which a well-known myxomycete biota *** general terms the hypotheses of the relationship between the myxomycete assemblages of areas used in this study agree with those reported for other groups of *** appear to show that a historical-geographic pattern influences the distribution of myxomycetes as much as environmental *** main clades were found in the analysis,with the first one including the two subantarctic localities,the second one representing the South American transition zone and the last one including all the Neotropical and Nearctic areas,but arranged into two subclades,one with the arid areas and the other with the tropical and temperate humid *** clade or subclade in the cladogram is supported by the presence of several morphospecies,some of which appear to represent endemic species restricted to specific geographic *** results of this analysis are proposed as a working hypothesis that can perhaps be supported in the future with new data from other complementary regions of America or with more intense surveys in the areas already *** are inconsistent with the hypothesis of cosmopolitan distribution for these microorganisms,as they appear to indicate groups of species that are restricted to certain geographic areas,some of which may be endemic,such as those from the subantarctic forests of South America,those found exclusively in the South American arid areas or those that have been recently described from arid ar

关键词： Andean region Distribution patterns Myxomycetes Nearctic Neotropics Ubiquity theory

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Developmental thyroid hormone action on pro-opiomelanocortin-expressing cells programs hypothalamic BMPR1A depletion and brown fat activation

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Journal of Molecular Cell Biology 2022年第9期14卷 54-67页

作者： Zhaofei Wu M.Elena Martinez Victoria DeMambro Marie Francois arturo Hernandez MaineHealth Institute for Research Center for Molecular MedicineMaineHealthScarboroughME 04074USA Graduate School of Biomedical Science and Engineering University of MaineOronoME 04469USA Naomi Berrie Diabetes Center Division of Molecular GeneticsColumbia University Irving Medical CenterNew YorkNY10032USA Department of Medicine Tufts University School of MedicineBostonMA 02111USA

Thyroid hormone excess secondary to global type 3 deiodinase(DIO3)deficiency leads to increased locomotor activity and reduced adiposity,but also to concurrent alterations in parameters of the leptin-melanocortin system that would predict *** distinguish the underlying contributions to the energy balance phenotype of Dlo3 deficiency,we generated mice with thyroid hormone excess targeted to pro-opiomelanocortin(POMC)-expressing cells via cell-specific DIO3 *** mice exhibit a male-specific phenotype of reduced hypothalamic Pomc expression,hyperphagia,and increased activity in brown adipose tissue,with adiposity and serum levels of leptin and thyroid hormones remained *** male mice also manifest a marked and widespread hypothalamic reduction in the expression of bone morphogenetic receptor 1a(BMPR1A),which has been shown to cause similar phenotypes when inactivated in PoMC-expressing *** results indicate that developmental overexposure to thyroid hormone in PoMC-expressing cells programs energy balance mechanisms in a sexually dimorphic manner by suppressing adult hypothalamic BMPR1A expression.

关键词： thyroid hormone type 3 deiodinase(DIO3) bone morphogenetic receptor 1a(BMPR1A) pro-opiomelanocortin(POMC) hyperphagia brown adipose tissue corticosterone

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Genes, emotions and gut microbiota:The next frontier for the gastroenterologist

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World Journal of Gastroenterology 2017年第17期23卷 3030-3042页

作者： arturo Panduro Ingrid Rivera-Iniguez Maricruz Sepulveda-Villegas Sonia Roman Department of Molecular Biology in Medicine Civil Hospital of Guadalajara“Fray Antonio Alcalde” Health Sciences Center University of Guadalajara

Most medical specialties including the field of gastroenterology are mainly aimed at treating diseases rather than preventing them. Genomic medicine studies the health/disease process based on the interaction of the human genes with the environment. The gastrointestinal(GI) system is an ideal model to analyze the interaction between our genes, emotions and the gut microbiota. Based on the current knowledge, this mini-review aims to provide an integrated synopsis of this interaction to achieve a better understanding of the GI disorders related to bad eating habits and stress-related disease. Since human beings are the result of an evolutionary process, many biological processes such as instincts, emotions and behavior are interconnected to guarantee survival. Nourishment is a physiological need triggered by the instinct of survival to satisfy the body's energy demands. The brain-gut axis comprises a tightly connected neuralneuroendocrine circuitry between the hunger-satiety center, the dopaminergic reward system involved in the pleasure of eating and the gut microbiota that regulates which food we eat and emotions. However, genetic variations and the consumption of high-sugar and high-fat diets have overridden this energy/pleasure neurocircuitry to the point of addiction of several foodstuffs. Consequently, a gut dysbiosis generates inflammation and a negative emotional state may lead to chronic diseases. Balancing this altered processes to regain health may involve personalized-medicine and genome-based strategies. Thus, an integrated approach based on the understanding of the gene-emotions-gut microbiota interaction is the next frontier that awaits the gastroenterologist to prevent and treat GI disorders associated with obesity and negative emotions.

关键词： Genes Emotions Brain reward system Gut microbiota Gastrointestinal disease Personalized medicine Genome-based nutrition Nutrigenetics Food decision-making Obesity

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Guidelines for rational design of high-performance absorbents:A case study of zeolite adsorbents for emerging pollutants in water

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Green Energy & Environment 2017年第4期2卷 363-369页

作者： Xiaoxuan Wei Ya Wang arturo J.Hernndez-Maldonado Zhongfang Chen Department of Chemistry Institute for Functional Nanomaterials University of Puerto Rico Rio Piedras Campus Department of Chemical Engineering Institute for Functional Nanomaterials University of Puerto Rico Mayagüez Campus

Rational design is important to achieve high-performance sorbents used to remove the contaminants of emerging concern(CECs) from ***, it is hard to propose effective design guidelines due to the lack of a clear understanding of the interaction mechanisms. By means of systematic quantum chemical computations, as a case study, we investigated the interactions between zeolite X/M^(n+)-zeolite X(Si/Al=1,M^(n+)=Cu^(2+) and Ni^(2+)) and three commonly used CECs(namely salicylic acid, carbamazepine and ciprofloxacin) in water to clarify the adsorption mechanisms. Our computations found that anionic salicylic acid cannot be adsorbed by neither zeolite X nor M^(n+)-zeolite X in neutral water due to the high electrostatic repulsion. In comparison, carbamazepine and ciprofloxacin have favorable binding energies with both zeolite X and M^(n+)-zeolite X, and their interactions with M^(n+)-zeolite X are stronger due to the joint effects of H-bond, metal complexation and electrostatic interaction. The adsorption loading of ciprofloxacin, which has a large molecular size, on M^(n+)-zeolite X is limited due to the steric hindrance. In general, steric hindrance, electrostatic interaction, H-bond and metal complexation are dominant factors for the examined systems in this study. Thus, for the design of high-performance absorbing materials, we should fully consider the molecular properties of pollutants(molecular size, surface electrostatic potential and atomic type, etc.), and properly enhance the favorable effects and avoid the unfavorable factors as much as possible under the guidance of the interaction mechanisms.

关键词： Adsorption mechanism Adsorbent design guidelines Quantum chemical computations Contaminants of emerging concern Zeolite X

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ON A CLASS OF RIEMANN SURFACES

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Analysis in Theory and Applications 2006年第4期22卷 377-386页

作者： arturo Fernández Javier Pérez Ciudad Universitaria Spain

It is considered the class of Riemann surfaces with dimT1=0, where T1 is a subclass of exactharmonic forms which is one of the factors in the orthogonal decomposition of the space Ω^H of harmonic forms of the surface, namely Ω^H=＊Ω^H＋T1＋＊T0^H＋T0^H＋T2The surfaces in the class OHD and the clase of planar surfaces satisfy dimT1 =0. *** posed the question whether there might exist other surfaces outside those two classes. Here it is shown that in the case of finite genus g, we should look for a surface S with dimTl = 0 among the surfaces of the form Sg／K , where Sg is a closed surface of genus g and K a compact set of positive harmonic measure with perfect components and very irregular boundary.

关键词： Harmonic form orthogonal decomposition Diriehlet norm

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Molecular Determinants of Antibiotic Resistance in the Costa Rican Pseudomonas aeruginosa AG1 by a Multi-omics Approach:A Review of 10 Years of Study

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Phenomics 2021年第3期1卷 129-142页

作者： Jose arturo Molina-Mora Fernando García Centro de Investigación en Enfermedades Tropicales(CIET)&Facultad de Microbiología Universidad de Costa RicaSan JoséCosta Rica

Pseudomonas aeruginosa AG1(PaeAG1)is a Costa Rican strain that was isolated in 2010 in a major *** strain has resistance to multiple antibiotics such asβ-lactams(including carbapenems),aminoglycosides,and ***1 is considered critical(Priority 1)due to its resistance to carbapenems,and it was the first report of a *** isolate carrying both VIM-2 and IMP-18 genes encoding for metallo-β-lactamases(MBL)enzymes(both with carbapenemase activity).Owing to these traits,we have studied this model for 10 years using diverse approaches including *** this review,we summarize the main points of the different steps that we have studied in PaeAG1:preliminary analyses of this strain at the genomic and phenomic levels revealed that this microorganism has particular features of antibiotic *** the multi-omics approach,the genome assembly was the initial step to identify the genomic determinants of this strain,includ-ing virulence factors,antibiotic resistance genes,as well as a complex accessory ***,a comparative genomic approach was implemented to define and update the phylogenetic relationship among complete *** genomes,the genomic island content in other strains,and the architecture of the two MBL-carrying ***,the proteomic profile of PaeAG1 was studied after exposure to antibiotics using 2-dimensional gel electrophoresis(2D-GE).Fourth,to study the central response to multiple perturbations in ***,i.e.,the core perturbome,a machine learning approach was *** analysis revealed biological functions and determinants that are shared by different ***,to evaluate the effects of ciprofloxacin(CIP)on PaeAG1,a growth curve comparison,differential expression analysis(RNA-Seq),and network analysis were *** the results of the core perturbome(pathways that also were found in this perturbation with CIP),it was possible to identify the“exclusive”response and determina

关键词： Pseudomonas aeruginosa PaeAG1 Antibiotic resistance Multi-omics High risk

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Robust flat filtering DSP based control of the boost converter

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Control Theory and Technology 2016年第3期14卷 224-236页

作者： Hebertt SIRA-RAMIREZ arturo HERNANDEZ-MENDEZ Jesus LINARES-FLORES Alberto LUVIANO-JUAREZ Department of Hectrical Engineering Mechatronics Section ClNVESTAV-IPN Av. IPN No. 2508 Col. San Pedro Zacatenco 07360 D.F. Mexico Mexico Universidad Tecnologica de la Mixteca Carretera a Acatlima Kin. 2.5 Huajuapan de Leon Oaxaca Mexico UPIITA-IPN D.F. Mexico Mexico

The article deals with the design and implementation of a flat filter tracking digital controller for a boost DC-DC power converter. A highly perturbed switched boost converter circuit is shown to be efficiently controlled, in a trajectory tracking task for its non-minimum phase output, by means of a suitable linear filter, here addressed as a flat filter. Flat filtering is a natural robust version of generalized proportional integral control （GPIC） by which the effects of arbitrary time varying exogenous disturbances, unknown endogenous nonlinearities and un-modeled dynamics can be jointly attenuated in a conceptually similar fashion to observer-based active disturbance rejection control （ADRC） and algebraic identification based model free control （MFC） but： a） without using extended state observers and b） respecting the original system order in a time-varying simplified model while avoiding algebraic estimation techniques. The proposed control technique based on the TMS320F28335 digital signal processor chip is tested by means of realistic simulations and experimental setup.

关键词： Flat filter DSP-implementation boost converter

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Genome-based nutrition:An intervention strategy for the prevention and treatment of obesity and nonalcoholic steatohepatitis

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World Journal of Gastroenterology 2015年第12期21卷 3449-3461页

作者： Sonia Roman Claudia Ojeda-Granados Omar Ramos-Lopez arturo Panduro Department of Molecular Biology in Medicine Civil Hospital of Guadalajara "Fray Antonio Alcalde"GuadalajaraJalisco Mexico and Health Sciences Center University of Guadalajara

Obesity and nonalcoholic steatohepatitis are increasing in westernized countries, regardless of their geographiclocation. In Latin America, most countries, including Mexico, have a heterogeneous admixture genome with Amerindian, European and African ancestries. However, certain high allelic frequencies of several nutrientrelated polymorphisms may have been achieved by past gene-nutrient interactions. Such interactions may have promoted the positive selection of variants adapted to regional food sources. At present, the unbalanced diet composition of the Mexicans has led the country to a 70% prevalence rate of overweightness and obesity due to substantial changes in food habits, among other factors. International guidelines and intervention strategies may not be adequate for all populations worldwide because they do not consider disparities in genetic and environmental factors, and thus there is a need for differential prevention and management strategies. Here, we provide the rationale for an intervention strategy for the prevention and management of obesity-related diseases such as nonalcoholic steatohepatitis based on a regionalized genome-based diet. The components required to design such a diet should focus on the specific ancestry of each population around the world and the convenience of consuming traditional ethnic food.

关键词： Latin America Mexico Gene-nutrient interactions Ev

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