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Glacial reconstruction and periglacial dynamics at the end of Late Pleistocene on the surface of Cofre de Perote volcano,méxico:a climatological retrospective

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Journal of mountain Science 2023年第9期20卷 2453-2467页

作者： Victor SOTO Hugo DELGADO-GRANADOS Carlos m.WELSH Kenji YOSHIKAWA Centro de Ciencias de la Tierra Universidad VeracruzanaXalapaVeracruz 91090México Instituto de Geofísica Universidad Nacional Autónoma de MéxicoCiudad de México 04150México Water and Environmental Research Center University of Alaska FairbanksFairbanksAlaska 99775USA

Despite being within the intertropical region of the planet,the mexican territory still has glacier-covered *** recent decades,important advances have been made in studies on glaciology and periglacial environment in mexico both for current and past ***,in spite of Cofre de Perote volcano(4200 m a.s.l.)being a strategically located mountain,it has not yet been studied in regards to the glacial and periglacial processes;in fact,those dynamics have modified the mountain massifs in the *** complement the series of studies on glacial history in the high mountain environment of méxico,this study reconstructs the glacial cover and the periglacial environment of the volcano surface during the final stage of the Late Pleistocene based on climatic retrospective and through the identification of geomorphological *** findings indicate the existence of a large glacier(ice cap)that covered the northern,western,and southern slopes of the mountain;while in the eastern sector there were two small glaciers,one being of cirque type,and the other of valley *** current temperature conditions prevent the occurrence of permanent ice bodies;at the same time,it was found that the periglacial blockfields of the slopes is a legacy of the climatic conditions that prevailed at the end of Late Pleistocene.

关键词： Cofre de Perote Glacial cover Periglacial environment Climatic retrospective Palaeoclimatic modelling

Obesity is associated with the Arg389Gly ADRB1 but not with the Trp64Arg ADRB3 polymorphism in children from San Luis Potosí and León,méxico

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The Journal of Biomedical Research 2017年第1期31卷 40-46页

作者： Celia Aradillas-García miguel Cruz Elva Perez-Luque maria E.Garay-Sevilla Juan m.malacara Aduna R Jesús Peralta Ana Burguete-García Jorge A.Alegría-Torres Faculty of medicine of the Autonomous University of San Luis Potosi MéxicoCIACYT-Facuity of MedicineC.P. 78210 San Luis Potosi S.L.P. México medical Research Unit in Biochemistry Hospital de EspecialidadesCentro Medico Nacional Siglo XXI del Instituto Mexicano del Seguro SocialMexico City C.P 06720 Mexico Department of medical Sciences Campus LeónUniversity of Guanajuato.LeónC.P.37320.México Chronic Infection and Cancer Division Research Center on Infectious DiseasesInstituto Nacional de Salud PublicaC.P.62100CuernavacaMorelosMéxico Department of Pharmacy Campus GuanajuatoUniversity of GuanajuatoNoria Alta C.P.36050GuanajuatoMéxico

This research was designed to analyze the possible associations of Arg389 Gly ADRB1 and Trp64 Arg ADRB3polymorphisms in children with obesity.A cross-sectional study included 1,046 school-age mexican participants（6-12 years old） from the cities of San Luis Potosi and *** were classified as non-obese or obese according to their body mass index（BmI） percentile;obese children had a BmI≥95th percentile for sex and *** data were *** were detected using Taqman qPCR assay.A logistic regression analysis was used to calculate the risk of obesity based on *** were found between groups where obese children had a significant increase in systolic and diastolic blood pressure,fasting plasma glucose,insulin,HOmAIR,LDL-cholesterol,triglycerides,and lower HDL-cholesterol compared with the normal weight group（P 〈 0.05）.The distribution of allele frequency in the population was Arg = 87.4 and Gly = 12.6（Hardy Weinberg equilibrium x^2= 3.16,P = 0.07）;Trp = 81.5 and Arg= 18.5（Hardy Weinberg equilibrium x^2 = 2.2,P = 0.14） for ADRB1 and ADRB3,*** though no different frequencies of Arg389 Gly polymoiphism between groups were found（P = 0.08）,children carriers of one Gly389,ADRB1 allele had a risk for obesity of OR = 1.40（95%CI,1.03-1.90,P =0.03） after adjustment for age and *** other association was found for Trp64 Arg ADRB3 *** the Arg389 Gly ADRB1 polymorphism was associated with risk for obesity in mexican children.

关键词： childhood obesity β-adrenergic receptor(ADRB) gene polymorphisms mexican children

molecular Assessment of Athecate Dinoflagellates of the Order Gymnodiniales (Dinophyceae) in Todos Santos Bay, Baja California méxico

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American Journal of Plant Sciences 2021年第12期12卷 1926-1944页

作者： Alexis De Jesús Escarcega-Bata mary Carmen Ruiz-de la Torre maría Luisa Nuñez Resendiz Luis manuel Enriquez-Paredes Kurt m. Dreckmann Abel Sentíes marine Science Faculty Autonomous University of Baja California Ensenada México Department of Hydrobiology Universidad Autónoma Metropolitana-Iztapalapa México México

The Gymnodiniales are the most important group of athecate dinoflagellates both for its abundance and distribution and for the harmful potential of several of its species. Although morphologically it is well known, phylogenetically it has been very little studied. HABs impact important coastal activities in Todos Santos Bay, so a detailed characterization of potentially toxic phytoplankton species is crucial in monitoring surveys. Therefore, the aim of the present study was to carry out a molecular assessment to the morphospecies of Gymnodiniales currently recorded in Todos Santos Bay, from which discussed their phylogenetic relationships. 120 samples were obtained from monthly samplings during 2019 to 2020. For all of them, 18 s small subunit (SSU) and 28 s large subunit (LSU) genes of rDNA were amplified and sequenced using single-cell PCR. Also, they were photographed. A phylogenetic analysis was performed on MrBayes from the combined 18 s - 28 s data set. The presence of 15 phylogenetic entities was confirmed, four of which constituted new records for the Mexican Pacific, as well as three harmful species, one toxic and two bloom-forming. Our molecular results evidenced the need to re-evaluate the current taxonomic system of athecate dinoflagellates at all hierarchical levels, integrating them with morphological evidence without preponderance of this criterion over taxonomic decisions.

关键词： Diversity HABS New Records Paraphyletic Groups Athecate Dinoflagellates

Identification of life habits factors as risk for gastritis and colitis occurrence in a mestizo population of Chabeklumil, Chiapas, méxico

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Open Journal of Nursing 2012年第2期2卷 67-71页

作者： Diana Cecilia Tapia-Pancardo Ramiro Jesús-Sandoval myrna miriam Valera-mota José Luis Cadena-Anguiano miguel murguía-Romero Rafael Villalobos-molina Carrera de Cirujano Dentista FES Iztacala Universidad Nacional Autónoma de México Tlalnepantla México Carrera de médico Cirujano FES Iztacala Universidad Nacional Autónoma de México Tlalnepantla México Carrera de Optometría FES Iztacala Universidad Nacional Autónoma de México Tlalnepantla México División de Investigación y Posgrado FES Iztacala Universidad Nacional Autónoma de México Tlalnepantla México

Aim: Gastric diseases are a recent trend in morbidity in méxico. We aimed to identify most frequent life habits factors as risk for gastritis and colitis occurrence, in a mexican mestizo population in Chabeklumil, Chiapas. Population: This study was observational, descriptive, transversal and prospective;346 questionnaires were applied to individuals of both genders from 11 years of age, with low income and socio-economic status, after they signed the informed consent. An individual file was created by the nurses in Chabeklumil. The predominant gender in the population was female (56.1%), with a distribution of 166 among adulthood (19 - 59 years of age);among males (43.9%), 133 included adults. Results: We identified the following environmental risk factors to develop gastritis and colitis: long periods of daily fasting > consumption of irritant food and drink > stress, in females;in contrast, males reported alcohol and tobacco consumption > irritant food and drink > long periods of daily fasting > stress. We found statistical differences (P males and males, in drugs and alcohol consumption, fasting, and stress, but not in consumption of irritant foods, nor in colitis and gastritis prevalence. Conclusions: Females are most affected by life habits risk factors for gastritis/colitis, which occurs mainly due to lifestyle and “macho” culture, since women are precluded of a better living standard, they work hard in the field, and start early in the day without consuming a meal, which they eat late in the day once arriving home. People in Chabeklumil eat/drink a lot of irritant food like hot pepper and coffee, which damage the gastrointestinal system leading to gastritis and colitis. Furthermore, men started to consume drugs at early ages, a condition also involved in developing gastritis.

关键词： Gastritis Colitis Life Habits Risk Factors Poverty mexican mestizo Population

Diversity of Saxicolous Lichens along an Aridity Gradient in Central méxico

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Phyton-International Journal of Experimental Botany 2022年第4期91卷 827-840页

作者： JoséCarmen Soto-Correa Abraham Saldaña-Vega Víctor Hugo Cambrón-Sandoval Laura Concostrina-Zubiri mariela Gómez-Romero Facultad de Ciencias Naturales Universidad Autónoma de QuerétaroQuerétaro73230México Departamento de Biología y Geología Física y Química Inorgánica Tulipán s/nUniversidad Rey Juan CarlosMóstolesMadrid28933España Cátedra CONACYT–Facultad de Biología Universidad Michoacana de San Nicolás de HidalgoMoreliaMichoacán58030México

Lichens are symbiotic organisms that comprise a fungus and a photosynthetic partner wich are recognized as a good indicator of climate ***,our understanding of how aridity affects the diversity of saxicolous lichens in drylands is still *** evaluate the relationship between saxicolous lichen diversity and aridity in a central méxico dryland,a geographical transect was established of 100 km to build an aridity gradient in the semiarid zone of the State of Querétaro,mexico,comprising ten sampling sites with a 10 km *** richness,abundance and diversity of soil lichen species were recorded using two sampling methods:the quadrat-intercept and the line-intercept method,to compare their performance in assessing soil lichen diversity in *** number of species and Shannon diversity of saxicolous lichens were higher at intermediate values of the aridity index(AI=0.10-0.34).Quadrat intercept and point intercept methods gave quite similar results,which means that the selected method does not influence the results in a significant *** study confirms the role of saxicolous lichens as climate change indicators and reveals the importance of the sampling method selection in the evaluation of different parameters of soil lichen diversity in drylands.

关键词： Climate change drylands ecological indicators environmental stress precipitation temperature

Oxidative stress in brickmakers of Juárez City, Chihuahua, méxico: Case-control study

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Advances in Bioscience and Biotechnology 2012年第7期3卷 1051-1059页

作者： Leobardo manuel Gómez-Oliván Alba Yadira Corral-Avitia Katya Aimeé Carrasco-Urrutia Navor Armando González-Granados marcela Galar-martínez Nadia Neri-Cruz Hariz Islas-Flores Octavio Dublan-García Facultad de Enfermería y Nutriología Universidad Autónoma de Chihuahua Chihuahua México Laboratorio de Ciencias Ambientales Instituto de Ciencias Biomédicas Universidad Autónoma de Ciudad Juárez Juárez México Laboratorio de Toxicología Acuática Departamento de Farmacia Escuela Nacional de Ciencias Biológicas Instituto Politécnico Nacional México City México Laboratorio de Toxicología Ambiental Facultad de Química Universidad Autónoma del Estado de México Toluca México

A case-control study was conducted in a brickmaker’s community in Juarez City, Chihuahua in mexico. This population has been chronically exposed to a wide spectrum of potentially health-damaging pollutants that include coarse, fine and ultrafine particles, carbon monoxide (CO), oxides of nitrogen and sulphur, transitional metals, polycyclic aromatic hydrocarbons (PAHs), volatile organic compounds and bioaerosols. Lipid peroxidation level (LPX) and protein carbonyl content (PCC) help to evaluate oxidized protein content and activity of the antioxidant enzymes: superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx) were evaluated in blood samples of study participants. The group of occupationally exposed (OE) workers consisted of 30 individuals ranging in age from 25 to 55 years, with a mean of 15 years in a brick production-related job. The control group included 30 volunteers who were neither environmentally nor occupationally exposed to brick production activities and whose sociodemo-graphic characteristics were similar to the OE group. Results indicate that none of workers used any type of protective equipment (respirator or face mask, gloves, coveralls) during brick manufacturing. LPX and PCC significantly increased (p mpared to the control group. SOD, CAT and GPx activity was significantly increased (p mpared to the control group. Therefore, evaluation of stress oxidative biomarkers is advisable in order to assay chronic exposure to workers in brick manufacturing.

关键词： Oxidative Stress Brickmakers Chronic Exposure Biomarkers Juárez City

Soil Organic matter and Grain Yield of Rainfed maize in Luvisols of Campeche, méxico

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Agricultural Sciences 2019年第12期10卷 1602-1613页

作者： Juan medina-méndez Víctor H. Volke-Haller José I. Cortés-Flores Arturo Galvis-Spínola maría de J. Santiago-Cruz Instituto Nacional de Investigaciones Forestales Agrícolas y Pecuarias Campo Experimental Edzná Campeche México Colegio de Postgraduados Texcoco México

The organic matter is an important soil component, due its favorable effects on soil physical and chemical properties and, by consequence, on crop yields. So, the objective of this work was quantify the changes through the time of soil organic matter in rainfed maize (Zea mays L.) system, in a period of 30 years of continuous crop and in relation to system of natural vegetation system, and also the effects of these changes on the crop yield, in Luvisols soils of State of Campeche, méxico. In production cycle of 2004, 53 farmer plots in rainfed maize system of different land use time and five sites of forest natural vegetation system were sampled for soil, to quantify physical and chemical properties of soil, and it was taken data about climate, system management and crop yield. The data were analiced by regression analysis, considered the organic matter as function of land use time and factors of soil and management of system, and the crop yield as function of soil organic matter and factors of soil, climate and management of system. The soil organic matter diminished from 5.68% in forest natural vegetation system to 3.59% after 16 - 30 years of cultivation, and the soil annual incorporation of vegetative mulch (weeds and stubble of maize) increased the organic matter from 0.14% after 1 - 5 years to 0.46% after 16 - 30 years of cultivation. Without fertilization, the diminution of soil organic matter caused 907 kg⋅ha−1 less of maize yield, and the fertilization with 200 kg⋅ha−1 of diamonic phosphate (36 kg⋅N⋅ha−1 and 92 kg P2O5 ha−1) increased the maize yield 1224 kg⋅ha−1 after 1 - 5 years and 1421 kg⋅ha−1 after 16 - 30 years of cultivation, but not compensed less maize yield of 711 kg⋅ha−1 due the diminution of soil organic matter.

关键词： Zea mays L. Annual Crops Forest Natural Vegetation Land Use Time Soil Properties

Nitrate Removal Efficiency with Hydrophytes of Los Reyes Aztecas Lake Water, méxico

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Journal of Water Resource and Protection 2014年第11期6卷 945-950页

作者： maría Guadalupe miranda Antonina Galvan Lauraceli Romero Department Engineering of Hydraulic Processes Universidad Autónoma Metropolitana Mexico City México Department of Hydrobiology Universidad Autónoma Metropolitana Mexico City México

The study was carried out to evaluate six different hydrophytes which were tested associated by twos: 1) Lemna gibba and Ceratophyllum demersum, 2) Berula erecta and Lemna gibba, 3) Polygonum punctatum and Hydrocotyle ranunculoides, and 4) Polygonum punctatum and Azolla filiculoides, for the purpose of removing nitrate from the water of Reyes Aztecas Lake, which is located southeast of mexico City in Tláhuac District, mexico D.F. The average of removal efficiency was obtained in relation to the different hydrophytes associations based on five sampling stations. The statistical analysis revealed that there were no significant differences among hydrophytes, all show remarkable ability to remove nitrate in water.

关键词： Bioremediation Nitrate Hydrophytes

Reservoir Processes Related to Exploitation in Los Azufres (méxico) Geothermal Field Indicated by Geochemical and Production monitoring Data

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International Journal of Geosciences 2015年第9期6卷 1048-1059页

作者： Víctor manuel Arellano Rosa maría Barragán miguel Ramírez Siomara López Alfonso Aragón Adriana Paredes Emigdio Casimiro Lisette Reyes Instituto de Investigaciones Eléctricas Gerencia de Geotermia Cuernavaca México Comisión Federal de Electricidad Gerencia de Proyectos Geotermoeléctricos Morelia México Comisión Federal de Electricidad Residencia Los Azufres Campamento Agua Fría México

A combined analysis of geochemical and production data of 39 wells of the Los Azufres (mexico) geothermal field (227.4 mWe) over time was developed to investigate the exploitation-related processes for 2003-2011. In the south zone, important effects of reinjection were observed through Cl increases in some wells (up to 8000 mg/kg) while in wells with significant boiling, Cl has decreased. In most of the north zone wells, the variations in gas data indicated boiling and condensation of a highly gas-depleted brine, which seems to consist of reinjection fluids. It is suggested that this process maintains the production in the zone relatively stable. The main reservoir exploitation-related processes found were: 1) production of reinjection returns;for this, it was possible to distinguish a) wells that produce liquid and steam from injection, and b) wells that produce steam from injection and sometimes condensed steam from injection;2) boiling: two types of boiling were identified: a) boiling with steam gain, and b) boiling with steam loss. The results indicated that an effective reservoir recharge occurs since very moderate production declining rates were found.

关键词： Los Azufres Geothermal Field Well Simulation Fluid Geochemistry Well Bottom Conditions Production Wells