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Ar/N2/CH4 Glow Discharge at Low Pressures

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Journal of Physical Science and Application 2012年第8期2卷 283-288页

作者： Leomar Salazar-Flores Horacio Martinez-Valencia Alfonso guerrero-Tapia Pedro Guillermo reyes-Romero Posgrado en Ciencias Fisicas Universidad Nacional Autonoma de Mexico Avenida Universidad 1000 05000 Mdxico D.F. Mexico Instituto de Ciencias Fisieas Universidad Nacional Autonoma de Mexico Apartado postal 48-3 62251 Cuernavaca Morelos Mexico Estudiante del Posgrado de la Facultad de Ciencias Universidad Autonoma del Estado de Mexico Instituto Literario 100 Centro 50000 Toluca Estado de Mexico Mexico Facultad de Ciencias Universidad Autonoma del Estado de Mexico Instituto Literario 100 Centro 50000 Toluca Estado de Mexieo Mexico

Ar/N2/CH4 glow discharge at low-pressure are studied in a closed system. The plasma was produced in 79.6% N2-15.4% Ar- 5.0% CH4 ternary mixture at pressures between 0.5 and 10.0 Torr. The diagnostic has been made by optical emission spectroscopy （OES）. The principal species observed were： N2, N2＋, CH＋, CN, C2, C3, HI3, Ha, C＋ and At. It presents the behaviour of the bands and lines intensities as a function of the pressure. Also, it displays the ratios of intensities of N＋2 （391.44 nm）, CN （392.08 nm）, and H （486.13 nm） to that of the N2 （337.13 rim） as function of pressure. The ratios show a slow decreasing behavior as a function of the pressure. Being the CH/N2 ratio more highest and H/N2 ratio the lowest one. The variations of excited species at different pressures may change the subsequent chemical reactions in the gas phase significantly. The present results suggest that the ion-molecule and molecule-molecule reactions in the gas phase are likely to play a dominant role in the present pressures.

关键词： Glow discharge optical emission spectroscopy low pressure discharge titan's atmosphere.

Laser-Induced Breakdown Spectroscopy (LIBS) Applied in the Differentiation of Arabicaand RobustaCoffee

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Optics and Photonics Journal 2017年第10期7卷 181-195页

作者： Abigail María Díaz guerrero Luis Vidal Ponce Cabrera Teresa Flores reyes Rogelio Ortega Izaguirre Research Center forApplied Science and Advanced Technology Altamira Unit National Polytechnic Institute Altamira Mexico

Coffee is one of the most consumed and commercialized crops in the world, which is why there is a potential risk to find arabica coffee (an expensive variety) adulterated with robusta coffee (a cheaper variety). The currently used technique for certifying coffee, High Performance Liquid Chromatography (HPLC), requires the sample to be subjected to a chemical treatment prior to analysis;in addition, the equipment is bulky and can not be moved easily. Laser Induced Breakdown Spectroscopy (LIBS) is a technique which does not require that samples be subjected to a chemical pretreatment, and equipment is small and portable, this can save valuable time in coffee trading. The purpose of this research was to demonstrate that LIBS can be applied to solve various problems related with the coffee authentication. Green coffee pills with different concentrations of arabica and robusta varieties were analyzed by LIBS, the results were used in the construction of calibration curves for the detection of the degree of simulated adulteration in coffee. It was found that the relative intensities of Ca (392.4 nm), Sr (407.1 nm), N (500.5 nm) and Na (588.7 nm), as well as the intensity ratios of Ca II (392.4 nm)/N I (500.5 nm), Sr I (407.1 nm)/N I (500.5 nm)and N I (500.5 nm)/Na I (588.7 nm) can be used for this purpose. It is concluded that the differentiation of coffee and the detection of its adulteration is possible with the use of LIBS. Further, with the use of an Artificial Neural Network (ANN) of type Multilayer Perceptron, it was possible to correctly classify the spectra of arabica and robusta roasted coffee.

关键词： Laser Induced Breakdown Spectroscopy (LIBS) Calibration Curves Artificial Neural Network (ANN) Multilayer Perceptron

Integral Representation Formulas Related to the Lamé–Navier System

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Acta Mathematica Sinica,English Series 2020年第12期36卷 1341-1356页

作者： Ricardo ABREU-BLAYA Juan BORY-reyes Marcos Antonio-HERRERA-PELáEZ José María SIGARRETA-ALMIRA Facultad de Matemáticas Universidad Autónoma de GuerreroGuerreroMéxico Instituto Politécnico Nacional SEPI-ESIME-ZAC CD-MXMéxico

The paper provides integral representations for solutions to a certain first order partial differential equation natural arising in the factorization of the Lamé–Navier system with the help of Clifford analysis *** representations look like in spirit to the Borel–Pompeiu and Cauchy integral formulas both in three and higher dimensional setting.

关键词： Lamésystem Clifford analysis Dirac operator

Evaluation of the Marginal Adaptation in Metal Crowns Using CAD/CAM and Manual Wax Patterns

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Microscopy Research 2015年第2期3卷 26-32页

作者： Alan Sepulveda-Rodríguez Felipe guerrero-Martínez César Gaitan-Fonseca Takashi Komabayashi Enrique reyes-Vela David Masuoka Department of Stomatology Universidad Autónoma de Aguascalientes Aguascalientes Mexico Faculty of Dentistry Universidad Autónoma de San Luis Potosí San Luis Potosí Mexico Department of Endodontics West Virginia University Charleston USA

The aim of this study is to evaluate the maximum and minimum distances between the model and the cast crown of three techniques using Scanning Electron Microscopy (SEM). Three technique groups were used for this study: group A (control), traditional manual wax patterns;group B, dipping wax patterns;group C, resin patterns made with CAD/CAM. For each group, 10 samples were made using the same model, and then metal cast. Marginal accuracies of the samples were evaluated by performing gap measurements using SEM with a magnification of 1200× (minimum distance). The data were statistically analyzed using the one-way analysis of variance (ANOVA) at the 0.05 significance level. The average (standard deviation) of the minimum distance [μm] was 22.5 (12.1), 9.9 (4.3), and 14.7 (6.6), in groups A, B, and C, respectively. The average standard deviation of gap area [μm2] was 21667.2 (3476.4), 9906.4 (1512.1), and 16048.8 (8123). In the minimum distance comparison, groups A and B (p = 0.006) showed statistically significant results. In the gap area comparison, there was no statistical significance among groups A, B, and C (p = 0.174). The marginal adaptations of all three techniques were within a reported clinically acceptable range of margin.

关键词： Marginal Adaptation CAD/CAM Metal Caps Wax Pattern

Microstructural Characterization of Large Area C60Films Obtained by Conventional Microwave Oven Irradiation

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World Journal of Nano Science and Engineering 2012年第4期2卷 213-218页

作者： Jacobo Martínez-reyes Lucia Graciela Díaz Barriga-Arceo Luis Rendón-Vazquez Reynaldo Martínez-guerrero Néstor Romero-Partida Eduardo Palacios-González Vicente Garibay-Febles Jaime Ortiz-López IMP-Molecular Engineering Program México City México National Polytechnic Institute (IPN) ESFM UPALM México City México National Polytechnic Institute (IPN) ESIQIE UPALM México City México ROMFER S.A. de C.V. México City México UNAM-FCiencias México City México

In the present work the synthesis of C60 produced in a conventional microwave oven from the decomposition of camphor resin is reported. The polycrystalline structure of the sample was determined by X-Ray Diffraction (XRD), the sample showed several phases, the main phase corresponds to fullerene C60 ordered in a Face-Centered Cubic structure (FCC), with two more structures: one orthorhombic system and the other the monoclinic system coexisting also with graphite 2H phase. It was observed in a Scanning Electron Microscopy (SEM), that the sample formed thin films of stacked carbon. Whereas in a High Resolution Transmission Electron Microscopy (HRTEM), measurements in Bright Field mode revealed that the main phase of the material is C60 ordered in FCC structure and the elemental composition and atomic bonding state can be determined by analyzing the energy with the electron microscope by Elesctron Energy- Loss Spectroscopy (EELS), technique allowed confirm all the phase C60 established with XRD observations.

关键词： Microwave-Assisted Synthesis Carbon Film Fullerene

Modeling of Atmospheric Phenomena Using Non-homogeneous Poisson Process

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Journal of Environmental Science and Engineering(A) 2012年第8期1卷 1003-1006页

作者： Nahun Loya Hortensia reyes Francisco Tajonar Francisco Ariza Department of Mathematics and Physies Autonomous University of Puebla Puebla 72570 Mexico Department of Mathematics Autonomous University of Guerrero Chilpancingo Guerrero 39070 Mexico

The PPNH （non-homogenous Poisson processes） are frequently used as models for events that come about randomly in a given time period, for example, failure times, time of accidents occurrences, etc. In this work, PPNH is used to model monthly maximum observations of urban ozone corresponding to a period of five years from the meteorological stations of Merced, Pedregal and Plateros, located in the metropolitan area of Mexico City. The interest data are the times in which the observations surpassed the permissible level of ozone of 0.11 ppm, settled by the Mexican Official Norm （NOM-020-SSA 1-1993） to preserve public health.

关键词： Ozone non-homogeneous Poisson processes environmental and chemical covariates.

The Genome of Cucurbita argyrosperma (Silver- Seed Gourd) Reveals Faster Rates of Protein- Coding Gene and Long Noncoding RNA Turnover and Neofunctionalization within Cucurbita

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Molecular Plant 2019年第4期12卷 506-520页

作者： Josue Barrera-Red on do Enrique Ibarra-Laclette Alejandra Vazquez-Lobo Yocelyn T. Gutierrez-guerrero Guillermo Sanchez de la Vega Daniel Pinero Salvador Montes-Hernandez Rafael Lira-Saade Luis E. Eguiarte Departamento de Ecologia Evolutiva Instituto de Ecologia Universidad Nacional Aut6noma de Mexico Circuito Exterior s/n Anexo al Jardin Bot合nico 04510 Ciudad de Mexico Mexico Departamento de Estudios Moleculares Avanzados Instituto de Ecologia A.C. Carretera Antigua a Coatepec No. 351 Col. El Haya. C.P. Xalapa Veracruz 91070 Mexico Centro de Investigaciones en Biodiversidad y Conservacion Universidad Autdnoma del Estado de Morelos Av. Universidad 1001 Col. Chamilpa Cuernavaca Morelos 62209 Mexico Campo Experimental Bajio Instituto Nacional de In vestigaciones Forestales Agricolas y Pecuarias (INIFAP) Km 6.5 Carretera Celaya-San Miguel de Allen de Celaya Guanajuato 38110 Mexico UBIPRO Facultad de Estudios Superiores Iztacala Universidad Nacional Autdnoma de Mexico Av. de los Barrios #1 Col. Los Reyes Iztacala Tlanepantla Edo. de Mex 54090 Mexico

Whole-genome duplications are an important source of evolutionary novelties that change the mode and tempo at which genetic elements evolve within a genome. The Cucurbita genus experienced a wholegenome duplication around 30 million years ago, although the evolutionary dynamics of the coding and noncoding genes in this genus have not yet been scrutinized. Here, we analyzed the genomes of four Cucurbita species, in eluding a newly assembled genome of Cucurbita argyrosperma, and compared the gene con tents of these species with those of five other members of the Cucurbitaceae family to assess the evolutionary dynamics of protein-coding and long intergenic noncoding RNA (lincRNA) genes after the genome duplication. We report that Cucurbita genomes have a higher protein-coding gene birth-death rate compared with the genomes of the other members of the Cucurbitaceae family. C. argyrosperma gene families associated with pollination and transmembrane transport had significantly faster evolutionary rates. lincRNA families showed high levels of gene turnover throughout the phylogeny, and 67.7% of the lincRNA families in Cucurbita showed evidence of birth from the neofunctionalization of previously existing protein-coding genes. Collectively, our results suggest that the whole-genome duplication in Cucurbita resulted in faster rates of gene family evolution through the neofunctionalization of duplicated genes.

关键词： Cucurbita argyrosperma, comparative genomics molecular evolution neofunctionalization long noncoding RNA whole-genome duplication

Higher cardiovascular risk scores and liver fibrosis risk estimated by biomarkers in patients with metabolic-dysfunction-associated fatty liver disease

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World Journal of Hepatology 2022年第8期14卷 1633-1642页

作者： Giovanni Alejandro Salgado Alvarez Samanta Mayanin Pinto Galvez Uriel Garcia Mora Ana Delfina Cano Contreras Cristina Durán Rosas Bryan Adrián Priego-Parra Arturo Triana Romero Mercedes Amieva Balmori Federico Roesch Dietlen Sophia Eugenia Martinez Vazquez Ines Osvely Mendez guerrero Luis Alberto Chi-Cervera Raúl Bernal reyes Leonardo Alberto Martinez Roriguez Maria Eugenia Icaza Chavez Jose Maria Remes Troche Instituto de Investigaciones Médico-biologicas Universidad VeracruzanaVeracruz 91700VeracruzMexico Department of Gastroenterología Instituto Nacional de Ciencias Médicas y Nutrición Salvador ZubiránMéxico 14080MéxicoMexico Clínica de Especialidades Gastrointestinales y Hepáticas Hospital Star MedicaMerida 97133YucatanMexico Department of Gastroenterologia Sociedad Española de BeneficenciaPachuca 42000HidalgoMexico Department of Gastroenterologia Clínica de Rehabilitación Metabólica Digestiva y HepáticaMexico 14080MexicoMexico Department of Gastroenterologia Hospital Star Médica de MéridaMerida 97133YucatanMexico

BACKGROUND The definition of metabolic-dysfunction-associated fatty liver disease(MAFLD)allows identification of metabolically complicated *** risk scores are related to cardiovascular risk(CVR)scores and could be useful for the identification of patients at risk of systemic *** To evaluate the relationship between MAFLD and CVR using the Framingham risk score in a group of Mexican *** Cross-sectional,observational and descriptive study carried out in a cohort of 585 volunteers in the state of Veracruz with MAFLD *** risk of liver fibrosis was calculated with aspartate aminotransferase-to-platelet ratio index,nonalcoholic fatty liver disease score and fibrosis-4,as well as with transient hepatic elastography with Fibroscan~?.The CVR was determined by the Framingham *** One hundred and twenty-five participants(21.4%)with MAFLD criteria were evaluated,average age 54.4 years,63.2%were women,body mass index 32.3 kg/m~*** Framingham CVR was high in 43 patients(33.9%).Transient elastography was performed in 55.2%of volunteers;39.1%with high CVR and predominance in advanced fibrosis(F3–F4).The logistic regression analysis showed that liver fibrosis,diabetes and hypertension independently increased *** One of every three patients with MAFLD had a high CVR,and in those with high fibrosis risk,the CVR risk was even greater.

关键词： Fatty liver Cardiovascular risk Hepatic steatosis Fibrosis Liver disease

Mutational landscape of gastric adenocarcinoma in Latin America: A genetic approach for precision medicine

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Genes & Diseases 2022年第4期9卷 928-940页

作者： Dennis Cerrato-Izaguirre Yolanda I.Chirino Claudia M.García-Cuellar Miguel Santibáñez-Andrade Diddier Prada Angélica Hernández-guerrero Octavio Alonso Larraga Javier Camacho Yesennia Sánchez-Pérez Subdirección de Investigación Básica Instituto Nacional de Cancerología(INCan)TlalpanCiudad de MéxicoCP 14080Mexico Departamento de Farmacología Centro de Investigación y de Estudios Avanzados del I.P.N.(CINVESTAV)Ciudad de MéxicoCP 07360Mexico Unidad de Biomedicina Facultad de Estudios Superiores IztacalaUniversidad Nacional Autónoma de MéxicoLos Reyes IztacalaTlalnepantla de BazEstado de MéxicoCP 54090Mexico Departamento de Informática Biomédica Facultad de MedicinaUniversidad Nacional Autónoma de MéxicoCoyoacánCiudad de MéxicoCP 04510Mexico Department of Environmental Health Science Mailman School of Public HealthColumbia UniversityNew YorkNY 10027USA Servicio de Endoscopía Instituto Nacional de Cancerología(INCan)TlalpanCiudad de MéxicoCP 14080Mexico

Latin-America (LATAM) is the second region in gastric cancer incidence;gastric adenocarcinoma (GA) represents 95% of all cases. We provide a mutational landscape of GA highlighting a) germline pathogenic variants associated with hereditary GA, b) germline risk variants associated with sporadic GA, and c) somatic variants present in sporadic GA in LATAM, and analyze how this landscape can be applied for precision medicine. We found that Brazil, Chile, Colombia, Mexico, Peru, and Venezuela are the countries with more published studies from LATAM explicitly related to GA. Our analysis displayed that different germline pathogenic variants for the CDH1 gene have been identified for hereditary GA in Brazilian, Chilean, Colombian, and Mexican populations. An increased risk of developing somatic GA is associated with the following germline risk variants: IL-4, IL-8, TNF-α, PTGS2, NFKB1, RAF1, KRAS and MAPK1 in Brazilian;IL-10 in Chilean;IL-10 in Colombian;EGFR and ERRB2 in Mexican, TCF7L2 and Chr8q24 in Venezuelan population. The path from mutational landscape to precision medicine requires four development levels: 1) Data compilation, 2) Data analysis and integration, 3) Development and approval of clinical approaches, and 4) Population benefits. Generating local genomic information is the initial padlock to overcome to generate and apply precision medicine.

关键词： Ethnicities Genome Latin America Mutati on Precisi on medicine Stomach neoplasms