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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

Bayesian regularized quantile regression:A robust alternative for genome-based prediction of skewed data

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The Crop Journal 2020年第5期8卷 713-722页

作者： Paulino Pérez-Rodríguez Osval A.Montesinos-lópez Abelardo Montesinos-lópez JoséCross Colegio de Postgraduados MontecillosEdo.de México 56230Mexico Facultad de Telemática Universidad de ColimaColima 28040Mexico Departamento de Matemáticas Centro Universitario de Ciencias Exactas e Ingenierías(CUCEI)Universidad de GuadalajaraGuadalajaraJalisco 44430Mexico International Maize and Wheat Improvement Center(CIMMYT) Km 45 Carretera México-VeracruzTexcocoEdo.de México 56237Mexico

Genomic prediction(GP)has become a valuable tool for predicting the performance of selection candidates for the next breeding cycle.A vast majority of statistical linear models on which GP is based rely on the assumption of normality of the residuals and therefore on the response variable *** this study,we propose to use Bayesian regularized quantile regression(BRQR)in the context of GP;the model has been successfully used in other research *** evaluated the prediction ability of the proposed model and compared it with the Bayesian ridge regression(BRR;equivalent to genomic best linear unbiased predictor,GBlUP).In addition,BlUP can be used with pedigree information obtained from the coefficient of coancestry(ABlUP).We have found that the prediction ability of BRQR is comparable to that of BRR and,in some cases,better;it also has the potential to efficiently deal with outliers.A program written in the R statistical package is available as Supplementary material.

关键词： laplace distribution Robust regression Bayesian quantile regression Genomic-enabled prediction

Synthesis of advanced ceramics by hydrothermal crystallization and modified related methods

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Journal of Advanced Ceramics 2012年第3期1卷 204-220页

作者： JoséORTIZ-lANDEROS Carlos GÓMEZ-YÁÑEZ rig.berto lópez-juárez Iván DÁVAlOS-VElASCO Heriberto PFEIFFER Departamento de Ingeniería Metalúrgica Escuela Superior de Ingeniería Química e Industrias ExtractivasIPNUPALMAv.Instituto Politécnico Nacional s/nCP 07738México DFMéxico. Centro de Ciencias Aplicadas y Desarrollo Tecnológico Universidad Nacional Autónoma de MéxicoA.P.70-186CoyoacánMéxico D.F.México. Instituto de Investigaciones en Materiales Universidad Nacional Autónoma de MéxicoCircuito exterior s/nCiudad UniversitariaDel.CoyoacánCP 04510México DFMéxico.

The present article aims to give a brief overview about the advantages of the hydrothermal crystallization method for the synthesis of advanced *** is given,not only on the conventional hydrothermal crystallization,but also on some of its variants;such as ultrasound-assisted,electrochemical-assisted,microwave-assisted and surfactant-assisted hydrothermal methods which open up new opportunities for the synthesis of ceramic materials with novel properties demanded for advanced *** the current work the synthesis of barium titanate(BaTiO3),lithium metasilicate(li2SiO3)and sodium-potassium niobate(Na,K)NbO3 powders are reported as cases of study.

关键词： hydrothermal synthesis barium titanate li_(2)SiO_(3) potassium-sodium niobate

Simulation factors of steel continuous casting

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International Journal of Minerals,Metallurgy and Materials 2010年第3期17卷 267-275页

作者： A.Ramírez-lópez R.Aguilar-lópez A.Kunold-Bello J.González-Trejo M.Palomar-Pardavé Department of Materiales Metropolitan Autonomous University Institute Polytechnic National Institute Technologic Autonomous of Mexico

The factors involved in simulating the continuous casting process of steel and the effects of the factors on the thermal behavior were investigated. The numerical methods and the influence of some assumptions were also analyzed, such as nodes used to discretize the steel in array size and computing time to obtain good approaches. The results show that some of these factors are related with the design of the continuous casting plant （CCP）, such as geometrical configuration, and the operating conditions, such as water flow rate, heat removal coefficient in the mold, casting times, and casting speed in the strand, which affect the heat removal conditions over the temperature and solidification profiles.

关键词： continuous casting thermal behavior numerical method computer simulation

Computational algorithms to simulate the steel continuous casting

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International Journal of Minerals,Metallurgy and Materials 2010年第5期17卷 596-607页

作者： A. Ramírez-lópez G. Soto-Cortés M. Palomar-Pardavé M.A. Romero-Romo R. Aguilar-lópez Institute Polytechnic National(Mexico) Department of Materials Metropolitan Autonomous University

Computational simulation is a very powerful tool to analyze industrial processes to reduce operating risks and improve profits from equipment. The present work describes the development of some computational algorithms based on the numerical method to create a simulator for the continuous casting process, which is the most popular method to produce steel products for metallurgical industries. The kinematics of industrial processing was computationally reproduced using subroutines logically programmed. The cast steel by each strand was calculated using an iterative method nested in the main loop. The process was repeated at each time step （？t） to calculate the casting time, simultaneously, the steel billets produced were counted and stored. The subroutines were used for creating a computational representation of a continuous casting plant （CCP） and displaying the simulation of the steel displacement through the CCP. These algorithms have been developed to create a simulator using the programming language C＋＋. Algorithms for computer animation of the continuous casting process were created using a graphical user interface （GUI）. Finally, the simulator functionality was shown and validated by comparing with the industrial information of the steel production of three casters.

关键词： continuous casting simulation numerical method computational algorithm

liver histological changes and lipid peroxidation in the amphibian Ambystoma mexicanum induced by sediment elutriates from the lake Xochimilco

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Journal of Environmental Sciences 2016年第8期28卷 156-164页

作者： Esperanza Ortiz-Ordonez Eugenia lópez-lópez Jacinto Elías Sedeno-Díaz Esther Uría Ignacio Andrés Morales María Estela Pérez Mineko Shibayama Instituto Politécnico Nacional Depto.de Formación Básica e InterdisciplinariaCICS-USTAv.de los Maestros s/n.Col.Sto Instituto Politécnico Nacional Laboratorio de Evaluación de la Salud de Ecosistemas AcuáticosENCBProl.de Carpio y Plan de Ayala s/n.Col.Sto Instituto Politécnico Nacional Coordinación Politécnica para la SustentabilidadEdificio de la Biblioteca Nacional3er PisoAv.Instituto Politécnico Nacional s/nesq.Wilfrido MassieuCol Instituto Politécnico Nacional Laboratorio de HistologíaENCBProl.de Carpio y Plan de Ayala s/n.Col.Sto Unidad de Servicio Académico Acuario BiologíaFacultad de CienciasUniversidad Autónoma de MéxicoCiudad Universitaria laboratorio de Infectómica Centro de Investigación y de Estudios Avanzados del IPNAv.Instituto Politécnico Nacional

lacustrine sediments accumulate pollutants that input from the lake watershed and can be released to the water column by sediment resuspension; thus, pollutants can change their bioavailability and exert adverse effects to aquatic biota. Shallow-urban lakes are particularly susceptible to receive pollutants from urban discharges and sediment resuspension. lake Xochimilco, in Mexico City, an urban-shallow lake, faces multiple problems： urban sprawl, overexploitation of aquifers, drying of springs, discharge of wastewater from treatment plants, and sediment resuspension. The aquatic biota living in this ecosystem is continuously exposed to the release of pollutants from the sediments. We assessed the risk that pollutants released from sediments from lake Xochimilco, Touristic（TZ） and Agriculture zone（AZ）, can exert on a native amphibian species of the lake（Ambystoma mexicanum） through exposure bioassays to sediment elutriates. We evaluate alterations in the amphibian by three approaches： biochemical（level of lipid peroxidation,lPO）, cellular（ultrastructure） and the liver histology of A. mexicanum and we compare them with a batch control. Additionally, we assessed heavy metals（Pb, Cd and Hg） in *** from TZ showed the highest concentrations of the metals assessed. Organisms exposed to sediment elutriates from either study sites showed higher lPO values than control organisms（p 〈 0.05）. Organisms exposed to elutriates from the TZ showed the most conspicuous damages： hepatic vasodilation of sinusoids, capillaries with erythrocytes,leukocyte infiltration and cytoplasmic vacuolation in hepatocytes. The biological responses assessed reflected the risk that faces A. mexicanum when is exposed for prolonged periods to sediment resuspension in lake Xochimilco.

关键词： Elutriates Amphibian liver Histological alterations Ultrastructure Oxidative stress Metals Urban lake

Cutaneous Dengue Virus Inoculation Triggers Strong B Cell Reactions but Contrastingly Poor T Cell Responses

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Virologica Sinica 2020年第5期35卷 575-587页

作者： Edith Marcial-juárez julio García-Cordero Raúl Antonio Maqueda-Alfaro Rafael Eduardo Saucedo-lópez luvia Enid Sánchez-Torres leticia Cedillo-Barrón leopoldo Flores-Romo Department of Cell Biology Center for Advanced Research(CINVESTAV-IPN)The National Polytechnic Institute07360 Mexico CityMexico Department of Molecular Biomedicine Center for Advanced Research(CINVESTAV-IPN)The National Polytechnic Institute07360 Mexico CityMexico Immunology Department The National School of Biological Sciences(ENCB-IPN)The National Polytechnic Institute11340 Mexico CityMexico

Dengue is a global health problem without current specific treatment nor safe vaccines *** severe dengue is related to pre-existing non-neutralizing dengue virus(DENV)antibodies,the role of T cells in protection or pathology is *** cutaneous DENV infection in immunocompetent mice we previously showed the generation of PNA+germinal centers(GCs),now we assessed the activation and proliferation of B and T cells in draining lymph nodes(DlNs).We found a drastic remodelling of DlN compartments from 7 to 14 days post-infection(dpi)with greatly enlarged B cell follicles,occupying almost half of the DlN area compared to*24%in na?ve *** clusters of proliferating(Ki-67+)cells inside B follicles were found 14 dpi,representing*33%of B cells in DlNs but only*2%in noninfected *** GCs,we noticed an important recruitment of tingle body macrophages removing apoptotic *** contrast,the percentage of paracortex area and total T cells decreased by 14–16 dpi,compared to *** randomly distributed Ki-67+T cells were found,similar to non-infected ***69 expression by CD4+and CD8+T cells was minor,while it was remarkable in B cells,representing 1764.7%of change from basal levels 3 *** apparent lack of T cell responses cannot be attributed to apoptosis since no significant differences were observed compared to noninfected *** study shows massive B cell activation and proliferation in DlNs upon DENV *** contrast,we found very poor,almost absent CD4+and CD8+T cell responses.

关键词： Dengue virus(DENV) B and T cells proliferation lymphocyte activation lymph nodes In vivo cutaneous infection Immunocompetent mice

Cytotoxic effect of Spirulina platensis extracts on human acute leukemia Kasumi-1 and chronic myelogenous leukemia K-562 cell lines

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Asian Pacific Journal of Tropical Biomedicine 2017年第1期7卷 14-19页

作者： Flor Yohana Flores Hernandez Sanghamitra Khandual Inocencia Guadalupe Ramírez lópez Center for Investigation and Assistance in Technology Design for State of JaliscoC.P.45019ZapopanJaliscoMexico

Objective: To evaluate the cytotoxic effects of Spirulina platensis extracts on acute leukemia Kasumi-1 and chronic leukemia K-562 cancer cell ***: Various concentrations of Spirulina platensis extracts(0.25–50.00 mg/m l)obtained with different solvents were used to treat cell lines for 72 h. For cytotoxic effect studies, cell viability test with trypan blue solution, MTT assay and microscopic cytomorphological assessment were ***: Spirulina extract obtained with 70% ethanol showed significant cytotoxicity in K562 and Kasumi-1 cell lines. With trypan blue solution, IC_(50) values were found to be4.64 mg/m l for K-562 and 3.68 mg/m l for Kusumi-1 cell lines. Spirulina aqueous extract also showed cytotoxicity with trypan blue method, at a slightly higher dose; where IC_(50) values were 12.68 mg/m l for K-562 and 2.13 mg/m l for Kusumi-1 cell lines. The IC_(50) values were found 0.40 mg/m l for K-562 and 0.31 mg/m l for Kusumi-1 cell lines for the 70% ethanol extract according to the MTT assay. Spirulina extract obtained with water also showed cytotoxicity but the dose was a little higher where IC_(50) values were15.77 mg/m l for K-562 and 9.44 mg/m l for Kusumi-1 cell lines. The effect of cytotoxicity with ethanol extract is quite comparable with that observed for cyclophosphamide, which is a chemical used as anticancer ***: The cytotoxicity exhibited by Spirulina extract to cancer cell lines might be due to the presence of phytopigments(carotenoids, chlorophyll, phycocyanin) as well as polysaccharides that were reported previously as constituents of the extract. So crude extracts of Spirulina can be used as a source to develop anticancer drugs.

关键词： leukemia Cytotoxicity Spirulina Carotenoids

Identification of ta-siRNAs and Cis-nat-siRNAs in Cassava and Their Roles in Response to Cassava Bacterial Blight

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Genomics, Proteomics & Bioinformatics 2013年第3期11卷 172-181页

作者： Andrés Quintero Alvaro l. Pérez-Quintero Camilo lópez Departamento de Biología Universidad Nacional de Colombia

Trans-acting small interfering RNAs （ta-siRNAs） and natural cis-antisense siRNAs （cisnat-siRNAs） are recently discovered small RNAs （sRNAs） involved in post-transcriptional gene silencing, ta-siRNAs are transcribed from genomic loci and require processing by microRNAs （miRNAs）. cis-nat-siRNAs are derived from antisense RNAs produced by the simultaneous tran- scription of overlapping antisense genes. Their roles in many plant processes, including pathogen response, are mostly unknown. In this work, we employed a bioinformatic approach to identify ta-siRNAs and cis-nat-siRNAs in cassava from two sRNA libraries, one constructed from healthy cassava plants and one from plants inoculated with the bacterium Xanthomonas axonopodis pv. manihotis （Xam）. A total of 54 possible ta-siRNA loci were identified in cassava, including a homo- log of TAS3, the best studied plant ta-siRNA. Fifteen of these loci were induced, while 39 were repressed in response to Xam infection. In addition, 15 possible c/s-natural antisense transcript （cis-NAT） loci producing siRNAs were identified from overlapping antisense regions in the genome, and were found to be differentially expressed upon Xam infection. Roles of sRNAs were predicted by sequence complementarity and our results showed that many sRNAs identified in this work might be directed against various transcription factors. This work represents a significant step toward understanding the roles of sRNAs in the immune response of cassava.

关键词： ta-siRNA nat-siRNA Natural antisense transcriptCassava Xanthomonas