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Materials Sciences and Applications 2013年第11期4卷 739-745页

作者： Jorge Luis rosas-mendoza L. Perez-Arrieta miguel Aguilar-Frutis Ciro Falcony R. Vázquez-Arreguín Alejandro Miguel Rosas-Mendoza Centro de Investigación en Ciencia Aplicada y Tecnología Avanzada Instituto Politécnico Nacional México D.F. México Centro de Investigación en Ciencia Aplicada y Tecnología Avanzada Instituto Politécnico Nacional México D.F. México Unidad Profesional Interdisciplinaria de Biotecnología Instituto Politécnico Nacional México D.F. México Departamento de Física Centro de Investigación de Estudios Avanzados (CINVESTAV-IPN) México D.F. México Unidad Académica de Física Universidad Autónoma de Zacatecas (UAZ) Zacatecas México

A study of the phase transitions in superconducting thin films of the Thallium-Barium-Calcium-Copper (TBCCO) system is carried out. In particular, it was got the Tl-1223 phase. For this purpose, and using the ultrasonic spray pyrolysis technique, Barium-Calcium-Copper precursor films were first obtained. Upon deposition of the precursor films, and as a second step, they were thallium (Tl) diffused in the one-zone furnace at 860°C. This methodology resulted in superconducting films that showed a phase transition as follows: Tl-2223 → Tl-2223 + Tl-2212 → Tl-2212 → Tl-1223, achieved between 2 and 7 hours of thallium diffusion. The evidence of the phase transitions was corroborated by the experimental results of X-ray diffraction, energy dispersive spectroscopy and resistance-temperature measurements.

关键词： Superconductors Thin Films Ultrasonic Spray Pyrolysis

Patch isolation and shape predict plant functional diversity in a naturally fragmented forest

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Journal of Plant Ecology 2018年第1期11卷 136-146页

作者： Amaranta Arellano-Rivas J.Arturo De-Nova miguel A.Munguía-rosas Instituto de Investigación de Zonas Desérticas Universidad Autónoma de San Luís PotosíSan Luis Potosí78377México Laboratorio de Ecología Terrestre Departamento de Ecología HumanaCentro de Investigación y Estudios Avanzados del Instituto Politécnico Nacional(CINVESTAV)Mérida 97310México Facultad de Agronomía Universidad Autónoma de San Luís PotosíSan Luis Potosí78321México

Aims It is known that taxonomic diversity can be predicted by the spatial configuration of the habitat,in particular by its area and degree of iso-lation.However,taxonomic diversity is a poor predictor of ecosystem functioning.While functional diversity is strongly linked to the func-tionality and stability of ecosystems,little is known about how changes in the spatial configuration of the habitat affect functional diversity.In this study,we evaluated whether the spatial configuration of forest patches predicts the functional diversity of plants in a fragmented forest.Methods Five functional leaf traits(leaf dry matter content,leaf punch force,specific leaf area,leaf size and leaf thickness)were measured for 23 dominant plant species in 20 forest patches in a naturally fragmented forest on the yucatan Peninsula.Abundance-weighted multivariate and individual trait metrics of functional diversity were calculated and cor-related with size,degree of isolation and the shape of forest patches.Important Findings Patch shape was negatively correlated with multivariate and individ-ual trait(leaf dry matter content and leaf size)metrics of functional diversity.Patch isolation measures were also negatively correlated with individual trait(leaf dry matter content,leaf punch force and leaf size)metrics of functional diversity.In other words,greater patch shape irregularity and isolation degree impoverish plant func-tional variability.This is the first report of the negative effects of patch shape irregularity and isolation on the functional diversity of plant communities in a forest that has been fragmented for a long time.

关键词： forest fragmentation functional diversity habitat spatial configuration petenes yucatan

Survival and growth of dominant tree seedlings in seasonally tropical dry forests of Yucatan: site and fertilization effects

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Journal of Plant Ecology 2014年第5期7卷 470-479页

作者： Luis Salinas-Peba Víctor Parra-Tabla Julio Campo miguel A.Munguía-rosas Departamento de Ecología Tropical Campus de Ciencias Biológicas y AgropecuariasUniversidad Autónoma de YucatánKm.15.5 Carretera Mérida-XmatkuilYucatán 97000México Instituto de Ecología Universidad Nacional Autónoma de MéxicoA.p.70-275México D.F.04510México Departamento de Ecología Humana Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional(CINVESTAV)Km.6 Antigua carretera a ProgresoMérida 97310México

Aims Seasonally tropical dry forests of the Yucatan Peninsula are typically found in sites with nutrient-poor soils because of the recent geologi-cal origin of the region.The landscape is dominated by extensive karstic plates that shape environments where vegetation regenera-tion through seed germination may be limited by the availability of suitable microsites.In this study,we documented the survival and growth of seedlings from three dominant tree species(Bursera simaruba,Piscidia piscipula and Lysiloma latisiliquum)in seasonally tropical dry forests in Yucatan.Specifically,we evaluated the effect of nutrient addition(N and P,separately and in combination)on seedling survival and growth across three sites with differing levels of precipitation.Methods We conducted a nutrient addition experiment,whereby we estab-lished 12 plots of dimensions 10×10 m(100 m^(2))at each site,from which three plots were randomly selected to receive one of four treatments:N addition,P addition,N and P addition and no nutri-ent addition(controls).Prior to treatment application,in each plot,we planted 10 seedlings of each species in October 2010 and sub-sequently conducted surveys of plant growth and survival every 20 days from November 2010 to April 2011.Important Findings Overall,nutrient addition increased seedling survival and the mag-nitude of this effect was similar among sites.We did not observe an additive effect of the N+P treatment on survival.Similarly,we observed a positive effect of nutrient addition on seedling growth,but this effect was contingent upon site;regarding survival,the effects of N and P on seedling growth were not additive.These results suggest that seedling recruitment and growth in the three dominant species of trees in Yucatan are limited by nutrient avail-ability but that the magnitude of this effect,particularly on seedling growth,is specific for species and site.

关键词： growth nitrogen nutrient addition phosphorus seedling survival seasonally tropical dry forest

A Neuro-Fuzzy Approach for Automatic Detection of Breast Cancer Based on Raman Spectroscopy

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通讯和计算机（中英文版） 2014年第2期11卷 158-167页

作者： Francisco Javier Luna rosas Julio Cesar Martinez Romo Ricardo mendoza Gonzalez Valentin Lopez Rivas miguel Mora Gonzalez Gricelda Medina Veloz Computer Science Department Instituto Tecnologico de Aguascalientes Aguascalientes 20256 Mexico Centro Universitario de los Lagos Universidad de Guadalajara Jalisco 44100 Mexico Universidad Tecnologica del Norte de Aguascalientes Aguascalientes 20256 Mexico

The harmful presence of cancerous cells in the feminine breast brings as a result, breast cancer, illness that has spread widely lately, not only in Mexico, but in other parts of the planet. In this paper, we present a method of automatic breast cancer classification, in which a Raman signal is classified as coming from a biopsy of healthy tissue (class ? 1 ) or biopsy of diseased tissue (class ? 2 ); to do so, we created patterns from Raman spectra accurately measuring each Raman peak to provide naturally reduced data to a classifier; we used ANFIS (adaptative neuro-fuzzy inference system) classifier and high rates of correct classification were obtained. This provides the specialists with important clinical tools for a rapid and efficient automatic detection of breast cancer. We consider that our approach can be applicable to other kinds of cancer, e. g., lung, prostate, and stomach.

关键词：自适应神经模糊推理系统拉曼光谱自动检测乳腺癌模糊方法分类模式 ANFIS 前列腺癌

Novel contributions of multimodality imaging in hypertension:A narrative review

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World Journal of Hypertension 2015年第2期5卷 28-40页

作者： Erick Alexanderson-rosas Enrique Berríos-Bárcenas Aloha Meave Juan Carlos de la Fuente-Mancera Mariano Oropeza-Aguilar alejandro Barrero-Mier Andrea de Guadalupe Monroy-González Raul Cruz-mendoza Gerardo Yoshiaki Guinto-Nishimura Nuclear Cardiology Department National Institute of Cardiology Ignacio ChávezMexico City 14080Mexico Cardiac Magnetic Resonance Department National Institute of Cardiology Ignacio ChávezMexico City 14080Mexico

Hypertension is currently one of the most prevalent il nesses worldwide,and is the second most common cause of heart failure,only behind ischemic cardiomyopathy.The development of novel multimodality imaging techniques in recent years has broadened the diagnostic methods,risk stratification and monitoring of treatment of cardiovascular diseases available for clinicians.Cardiovascular magnetic resonance(CMR) has a great capacity to evaluate cardiac dimensions and ventricular function,is extremely useful in ruling-out ischemic cardiomyopathy,the evaluation of the vascular system,in making the differential diagnosis for resistant hypertension and risk stratification for hypertensive cardiomyopathy and constitutes today,the method of choice to evaluate left ventricular systolic function.Computed tomography(CT) is the method of choice for the evaluation of vascular anatomy,including coronary arteries,and is also able to provide both functional and structural information.Finally,nuclear cardiology studies have been traditionally used to evaluate myocardial ischemia,along with offering the capacity to evaluate ventricular,endothelial and cardiac innervation function;information that is key in directing the treatment of the patient.In this narrative review,the most recent contributions of multimodality imaging to the patient with hypertension(CMR,CT and nuclear cardiology) will be reviewed.

关键词： Cardiac imaging techniques Multimodality imaging Magnetic resonance imaging Multidetector computed tomography Cardiac-gated single photon emission computed tomography Positron emission tomography Hypertension

Synthesis and Characterization of Green Potassium Nanoparticles from Sideroxylon Capiri and Evaluation of Their Potential Antimicrobial

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Journal of Renewable Materials 2021年第10期9卷 1699-1706页

作者： Judith Constantino-Alcazar miguel Abud-Archila Benjamín Valdez-Salas Federico Gutierrez-Miceli Carlos Ceceña-Duran Blanca López-Valenzuela Daniel Gonzalez-mendoza Tecnológico Nacional de México Instituto Tecnológico de Tuxtla GutiérrezTuxtlaGutiérrezC.P.03940México Instituto de Ciencias Agrícolas de la Universidad Autónoma de Baja California(ICA-UABC) Ejido Nuevo LeónC.P.21705México Instituto de Ingeniería de la Universidad Autónoma de Baja California Mexicali21100México

In the present study,the green synthesis of potassium nanoparticles(K-NPs)was assessed using aqueous extract of Sideroxylon capiri.The potassium nanoparticles were analyzed by UV-visible spectroscopic techniques,X-ray spectrometers of energy dispersive(SEM-EDS)and dynamic light scattering.The results showed high values at 3.5 keV confirming the formation of potassium nanoparticles and the SEM analysis showed an agglomerated particles size between 360 to 200 nm with a spherical morphology.The K-NPs showed an effective antibacterial activity against the test organisms mainly with Bacillus cereus,Enterobacter aerogenes,Fusarium solani and Botrytis cinerea.However further studies about nanotoxicity of K-NPs are needed to confirm their potential in the control of the pathogen microorganisms under field conditions.

关键词： Antimicrobial effect green synthesis Sideroxylon capiri biocontrol

Long-term effects of gestational diabetes mellitus on the pancreas of female mouse offspring

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World Journal of Diabetes 2024年第4期15卷 758-768页

作者： Enriqueta Muñoz-Islas Edgar David Santiago-SanMartin Eduardo mendoza-Sánchez Héctor Fabián Torres-Rodríguez Laura Yanneth Ramírez-Quintanilla Christopher Michael Peters Juan miguel Jiménez-Andrade Unidad Académica Multidisciplinaria Reynosa-Aztlán Universidad Autónoma de TamaulipasReynosa 88740TamaulipasMexico Department of Anesthesiology Wake Forest University School of MedicineWinston SalemNC 27101United States

BACKGROUND Prolonged fetal exposure to hyperglycemia may increase the risk of developing abnormal glucose metabolism and type-2 diabetes during childhood,adolescence,and adulthood;however,the mechanisms by which gestational diabetes mellitus(GDM)predisposes offspring to metabolic disorders remain unknown.AIM To quantify the nerve axons,macrophages,and vasculature in the pancreas from adult offspring born from mouse dams with GDM.METHODS GDM was induced by i.***.administration of streptozotocin(STZ)in ICR mouse dams.At 12 wk old,fasting blood glucose levels were determined in offspring.At 15 wk old,female offspring born from dams with and without GDM were sacrificed and pancreata were processed for immunohistochemistry.We quantified the density of sensory[calcitonin gene-related peptide(CGRP)]and tyrosine hydroxylase(TH)axons,blood vessels(endomucin),and macro-phages(CD68)in the splenic pancreas using confocal microscopy.RESULTS Offspring mice born from STZ-treated dams had similar body weight and blood glucose values compared to offspring born from vehicle-treated dams.However,the density of CGRP+and TH+axons,endomucin+blood vessels,and CD68+macrophages in the exocrine pancreas was significantly greater in offspring from mothers with GDM vs control offspring.Likewise,the microvasculature in the islets was significantly greater,but not the number of macrophages within the islets of offspring born from dams with GDM compared to control mice.CONCLUSION GDM induces neuronal,vascular,and inflammatory changes in the pancreas of adult progeny,which may partially explain the higher propensity for offspring of mothers with GDM to develop metabolic diseases.

关键词： Gestational diabetes mellitus Immunohistochemistry Confocal microscopy Pancreas Offspring

Insulin:A connection between pancreaticβcells and the hypothalamus

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World Journal of Diabetes 2023年第2期14卷 76-91页

作者： Brenda De la Cruz Concepción Yaccil Adilene Flores Cortez Martha Isela Barragán Bonilla Juan miguel mendoza Bello Monica Espinoza Rojo Molecular and Genomic Biology Laboratory Faculty of Chemical-Biological SciencesAutonomous University of GuerreroChilpancingo 39070GuerreroMexico

Insulin is a hormone secreted by pancreaticβcells.The concentration of glucose in circulation is proportional to the secretion of insulin by these cells.In target cells,insulin binds to its receptors and activates phosphatidylinositol-3-kinase/protein kinase B,inducing different mechanisms depending on the cell type.In the liver it activates the synthesis of glycogen,in adipose tissue and muscle it allows the capture of glucose,and in the hypothalamus,it regulates thermogenesis and appetite.Defects in insulin function[insulin resistance(IR)]are related to the development of neurodegenerative diseases in obese people.Furthermore,in obesity and diabetes,its role as an anorexigenic hormone in the hypothalamus is diminished during IR.Therefore,hyperphagia prevails,which aggravates hyperglycemia and IR further,becoming a vicious circle in which the patient cannot regulate their need to eat.Uncontrolled calorie intake induces an increase in reactive oxygen species,overcoming cellular antioxidant defenses(oxidative stress).Reactive oxygen species activate stress-sensitive kinases,such as c-Jun Nterminal kinase and p38 mitogen-activated protein kinase,that induce phosphorylation in serine residues in the insulin receptor,which blocks the insulin signaling pathway,continuing the mechanism of IR.The brain and pancreas are organs mainly affected by oxidative stress.The use of drugs that regulate food intake and improve glucose metabolism is the conventional therapy to improve the quality of life of these patients.Currently,the use of antioxidants that regulate oxidative stress has given good results because they reduce oxidative stress and inflammatory processes,and they also have fewer side effects than synthetic drugs.

关键词： Insulin Pancreas Hypothalamus Hyperphagia Hyperglycemia Stress

Antibacterial activity of five Peruvian medicinal plants against Pseudomonas aeruginosa

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Asian Pacific Journal of Tropical Biomedicine 2015年第11期5卷 928-931页

作者： Gabriela Ulloa-Urizar miguel Angel Aguilar-Luis María del Carmen De Lama-Odría José Camarena-Lizarzaburu Juana del Valle mendoza Centro de Investigacin de la Facultad de Ciencias de la Salud Universidad Peruana de Ciencias Aplicadas-UPC Facultad de Ciencias Biolgicas Universidad Nacional Mayor de San Marcos (UNMSM) Instituto de Investigacin Nutricional

Objective: To evaluate the susceptibility of Pseudomonas aeruginosa(P. aeruginosa)in vitro to the ethanolic extracts obtained from five different Peruvian medicinal plants.Methods: The plants were chopped and soaked in absolute ethanol(1:2, w/v). The antibacterial activity of compounds against P. aeruginosa was evaluated using the cupplate agar diffusion method.Results: The extracts from Maytenus macrocarpa("Chuchuhuasi"), Dracontium loretense Krause("Jergon Sacha"), Tabebuia impetiginosa("Tahuari"), Eucalyptus camaldulensis Dehn(eucalyptus), Uncaria tomentosa("U?a de gato") exhibited favorable antibacterial activity against P. aeruginosa. The inhibitory effect of the extracts on the strains of P. aeruginosa tested demonstrated that Tabebuia impetiginosa and Maytenus macrocarpa possess higher antibacterial activity.Conclusions: The results of the present study scientifically validate the inhibitory capacity of the five medicinal plants attributed by their common use in folk medicine and contribute towards the development of new treatment options based on natural products.

关键词： Pseudomonas Medicinal plants Maytenus macrocarpa D

Excess Levels of ILysine and Threonine in Low Protein, Wheat-based Diets on Serum Amino Acid Concentrations and Performance of Growing Pigs

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Journal of Agricultural Science and Technology(A) 2012年第5期2卷 619-627页

作者： Adriana Morales JoseLuis Landero Alfonso Araiza Hugo Bernal Willem C. Sauer Antonio rosas miguel Cervantes Instituto de Ciencias Agrlcolas Universidad Aut6noma de Baja California Mexicali Baja California 21100 Mexico Facultad de Agronomla Universidad Autonoma de Nuevo Leon Monterrey Mexico IlAF Universidad Michoacana de San Nicolas de Hidalgo Morelia Mich Mexico