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A cellular automata model for simulating grain structures with straight and hyperbolic interfaces

International Journal of minerals,metallurgy and materials 2012年第8期19卷 699-710页

作者： A.Ramírez-lópez m.Palomar-Pardavé D.muñoz-Negrón C.Duran-Valencia s.lópez-Ramirez G.soto-Cortés materials and Energy Department Metropolitan Autonomous UniversityMexico Department of Industrial Engineering Technological Autonomous Institute of MexicoMexico Department of molecular Engineering Mexican Institute of PetroleumMexico

A description of a mathematical algorithm for simulating grain structures with straight and hyperbolic interfaces is shown. The presence of straight and hyperbolic interfaces in many grain structures of metallic materials is due to different solidification conditions, in- eluding different solidification speeds, growth directions, and delaying on the nucleation times of each nucleated node. Grain growth is a complex problem to be simulated; therefore, computational methods based on the chaos theory have been developed for this purpose. straight and hyperbolic interfaces are between columnar and equiaxed grain structures or in transition zones. The algorithm developed in this work involves random distributions of temperature to assign preferential probabilities to each node of the simulated sample for nucleation according to previously defined boundary conditions. moreover, more than one single nucleation process can be established in order to gen- erate hyperbolic interfaces between the grains. The appearance of new nucleated nodes is declared in sequences with a particular number of nucleated nodes and a number of steps for execution. This input information influences directly on the final grain structure （grain size and dislribution）. Preferential growth directions are also established to obtain equiaxed and columnar grains. The simulation is done using rou- tines for nucleation and growth nested inside the main function. Here, random numbers are generated to place the coordinates of each new nucleated node at each nucleation sequence according to a solidification probability. Nucleation and growth routines are executed as a func- tion of nodal availability in order to know if a node will be part of a grain. Finally, this information is saved in a two-dimensional computa- tional array and displayed on the computer screen placing color pixels on the corresponding position forming an image as is done in cellular automaton.

关键词： grain growth interfaces grain size and shape computational methods algorithms cellular automata computer simulation

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Transcriptional Regulation and signaling in Phosphorus starvation: What About legumes?

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Journal of Integrative Plant Biology 2008年第10期50卷 1213-1222页

作者： Oswaldo Valds-lópez Georgina Hernndez Centro de Ciencias Genómicas Centre for Genomic sciences Universidad Nacional Autónoma de Mxico National University of MexicoCuernavaca Morelos 62210 Mxico

The availability of soil phosphorus （P）, an essential element, is one of the most important requirements for plant growth and crop production. The morphological and physiological adaptations evolved by plants to cope with P starvation have been well characterized. several P deficiency plant responses are regulated at the transcriptional level. microarray analysis has generated valuable information on global gene expression in Arabidopsis thaliana grown under P-stress. Despite the identification of P responsive genes, little is known about the regulation of gene expression changes. Four transcription factors, PHRI, WRKY75, ZAT6 and BHlH32, involved in P starvation signaling have been characterized in Arabidopsis, and signaling pathways are deciphered. This review analyzes the current knowledge of transcriptional regulation of P starvation responses in Arabidopsis vis-a-vis legumes such as lupine, common bean and medicago truncatula. The knowledge on regulatory and signaling mechanisms involved in P acquisition and use in legumes will be useful for improvement of these crops, which account for a large proportion of the world＇s crop production, providing good nutritional quality feed and food.

关键词： legumes phosphorus starvation responses P starvation signaling pathways transcriptional regulation transcription factors.

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Evaluation of mandibular Deprogramming Using TENs (Transcutaneous Electrical Nerve stimulation) in Patients at the specialty Clinic of the Juarez Autonomous University of Tabasco from 2022 to 2024

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Journal of Biosciences and medicines 2024年第7期12卷 245-251页

作者： Christian C. Aguilar-Caamal landy V. limonchi-Palacio Crystell G. Guzmán-Priego Jeannette Ramírez-mendoza José m. lehmann-mendoza miguel A. lópez-Alvarado Xavier E. moreno-Enriquez Jorda A. Albarrán-melzer Academic Division of Health sciences Juarez Autonomous University of Tabasco Villahermosa Tabasco Mxico Cardiometabolism laboratory Academic Division of Health Sciences Juarez Autonomous University of Tabasco Villahermosa Tabasco Mxico

Temporomandibular disorders (TmD) negatively affect quality of life, causing pain and restricted jaw movements. This study evaluates the effectiveness of Transcutaneous Electrical Nerve stimulation (TENs) on TmD patients before orthodontic treatment at the Juarez Autonomous University of Tabasco. A quantitative, quasi-experimental study was conducted with 30 patients who met the inclusion criteria: aged 18 to 65 years, with TmJ pain symptoms, diagnosed with temporomandibular disorders using the Helkimo index, and who had provided informed consent for the study. The range of mandibular movement and the Visual Analog scale (VAs) were measured to record values before therapy. The electrodes of the TENs therapy were positioned on both sides of the jaw in the preauricular area and the masseter muscle, the therapy was administered for 40 minutes, utilizing a frequency of 2 - 4 Hz and a pulse duration of 300 microseconds. Following this, the range of mandibular movement and the VAs were reassessed to evaluate the outcomes., significantly improved maximum mouth opening (37.7 ± 6.4 mm to 44.6 ± 5.88 mm), right laterality (3.86 ± 1.57 mm to 5.43 ± 1.21 mm), left laterality (3.13 ± 1.63 mm to 4.53 ± 1.61 mm), protrusion (4.01 ± 1.7 mm to 5.36 ± 1.32 mm), and pain perception (4.56 ± 2.045 to 2.03 ± 1.5) (P s therapy enhances mandibular movement and reduces pain, making it a well-tolerated, non-invasive complementary treatment for TmD.

关键词： TENs Opening Deprogramming Electrostimulation TmJ (Temporomandibular Joint)

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Intestinal pseudo-obstruction in patients with systemic lupus erythematosus: A real diagnostic challenge

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World Journal of Gastroenterology 2014年第32期20卷 11443-11450页

作者： Carlos Alberto García lópez Fernando laredo-sánchez José malagón-Rangel miguel G Flores-Padilla Haiko Nellen-Hummel Department of Internal medicine Specialities Hospital National Medical Centre "Siglo XXI" Mexican Social Security Institute Distrito Federal 06720 México

Intestinal pseudo-obstruction secondary to systemic lupus erythematosus(slE) is a rare syndrome described in recent decades. There are slightly over 30 published cases in the English language literature, primarily associated with renal and hematological disease activity. Its presentation and evolution are a diagnostic challenge for the clinician. We present four cases of intestinal pseudo-obstruction due to lupus in young mexican females. One patient had a previous diagnosis of slE and all presented with a urinary tract infection of varying degrees of severity during their evolution. We consider that recognition of the disease is of vital importance because it allows for establishing appropriate management, leading to a better prognosis and avoiding unnecessary surgery and complications.

关键词： Intestinal pseudo-obstruction systemic lupus erythematosus Uretero-hydronephrosis Urinary tract infection Diagnostic challenge

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Trichoderma *** Bacillus *** growth promoters in maize(Zea mays l.)

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Phyton-International Journal of Experimental Botany 2019年第1期88卷 37-46页

作者： lópez-Valenzuela BE Armenta-Bojórquez AD Hernández-Verdugo s Apodaca-sánchez mA samaniego-Gaxiola JA Valdez-Ortiz A Universidad Autónoma de sinaloa.Facultad de Agricultura del Valle del Fuerte.Avenida Japaraqui y Calle 16 s/n Juan JoséRíosSinaloaC.P 81110México Universidad Autónoma de Baja California.Instituto de Ciencias Agrícolas.Carretera a Delta s/n Ejido Nuevo leónBaja CaliforniaC.P.21705México Instituto Politécnico Nacional.Centro Interdisciplinario de Investigación para el Desarrollo Integral Regional Unidad sinaloa.Blvd.Juan de Dios Bátiz Paredes#250 Colonia San JoachinGuasaveSinaloaC.P.81101México Universidad Autónoma de sinaloa Facultad de Agronomía.Km.17.5Carretera Culiacán-El DoradoCuliacán RosalesSinaloaC.P.80000México Instituto Nacional de Investigaciones Forestales Agrícolas y Pecuarias Campo Experimental La LagunaBlvd.JoséSantos Valdez 1200 Pte.MatamorosCoahuilaC.P.27440México Universidad Autónoma de sinaloa Facultad de Ciencias Químico Biológicas.Calzada de las Américas y Calle Universitarioss/n.Ciudad UniversitariaCuliacánSinaloaC.P.80013México

microbes that are beneficial to plants are used to enhance the crop growth,yield and are alternatives to chemical *** and Bacillus are the predominant plant growth-promoting fungi and *** objective of this study was select,characterize,and evaluate isolates of Trichoderma *** Bacillus *** from the northern region of sinaloa,mexico,and assess their effect on growth promotion in maize(Zea mays l.).In greenhouse conditions,four Trichoderma isolates and twenty Bacillus isolates,as well as two controls,were tested in a completely randomized design with three *** selected the two best strains of Trichoderma and Bacillus:TB=Trichoderma asperellum,TF=Trichoderma virens,B14=Bacillus cereus sensu lato and B17=Bacillus cereus,which were evaluated in the field in a completely randomized blocks in factorial arrangement design with three replicates applying different rates of nitrogen fertilizer(0,150 kg N/ha,and 300 kg N/ha).Treatments 5(B17=***)and 11(TF=***)both fertilized with 150 kg N/ha showed similar yields and they did not reveal significant differences from the treatments fertilized with 300 kg N/*** indicated that treatment 5(B17=*** with 150 kg N/ha)and treatment 11(TF=*** with 150 kg N/ha)were efficient as growth promoters,by not showing significant differences in root volume and dry weight of *** results indicated a reduction of 50% in the rate of nitrogen to fertilizer required for maize(Zea mays l.)*** microorganisms Trichoderma and Bacillus could be an alternative to reduce the use of chemical fertilizers in maize.

关键词： Trichoderma Bacillus Native strains Biofertilizers

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A look into the past, present and future potential distributions of Talinopsis frutescens, a North American endemic lineage closely related to Cactaceae

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Journal of Arid land 2020年第1期12卷 104-114页

作者： mónica I mIGUEl-VÁZQUEZ Yasser s lÓpez DE OlmOs R Gilberto OCAmPO Department of Biology Basic Sciences CenterAutonomous University of Aguascalientes940 University AvenueAguascalientes 20130Mexico Biological and Health sciences PhD Program Department of BiologyBiological and Health Sciences DivisionAutonomous Metropolitan UniversityIztapalapa 09340Mexico

Talinopsis frutescens(Anacampserotaceae,a family that is close related to Cactaceae)is a succulent species endemic to North *** aim of this study was to explore,using Ecological Niche modeling(ENm),changes in potential distribution ranges considering different climate scenarios:past conditions during the last Inter Glacial(lIG)and the last Glacial maximum(lGm),the present and projections for 2070(RCP 2.6 to 8.5).A pattern of contraction is observed during the lIG,which agrees with other studies focused in species from arid *** pattern was followed by a migration towards the south during the lGm and a possible recent expansion to the north as is observed in the present *** future projections show the same contraction and fragmentation patterns,resulting in three discontinuous areas:the northern part of the Chihuahuan Desert,the southern-central part of the mexican Plateau,and the smallest one in the Tehuacán-Cuicatlán *** projections for future scenarios agree with other studies and support that global climate change tends to alter the current distribution of arid environment species.

关键词： Anacampserotaceae Caryophyllales ecological niche modeling succulent plants potential distribution

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simulation of heat transfer in steel billets during continuous casting

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International Journal of minerals,metallurgy and materials 2010年第4期17卷 403-416页

作者： A.Ramirez-lópez R.Aguilar-lópez m.Palomar-Pardavé m.A.Romero-Romo D.muoz-Negrón Department of materials metropolitan Autonomous University Mexico City C.P.02200Mexico Institute Polytechnic National Mexico City C.P.07300Mexico Institute Technologic Autonomous of mexico Mexico City C.P.01080Mexico Institute Polytechnic National mexico City C.P.07300 Mexico

This work is focused on the development of computational algorithms to create a simulator for solving the heat transfer during the continuous casting process of steel. The temperatures and the solid shell thickness profiles were calculated and displayed on the screen for a billet through a defined continuous casting plant （CCP）. The algorithms developed to calculate billet temperatures, involve the solutions of the corresponding equations for the heat removal conditions such as radiation, forced convection, and conduction according to the billet posi- tion through the CCP. This is done by a simultaneous comparison with the kinematics model previously developed. A finite difference method known as Cmnk-Nicholson is applied to solve the two-dimensional computational array （2D model）. Enthalpy （HIJ） and temperature （TIl） in every node are updated at each step time. The routines to display the results have been developed using a graphical user interface （GUI） in the programming language C＋＋. Finally, the results obtained are compared with those of industrial trials for the surface temperature of three steel casters with different plant configurations in different casting conditions.

关键词： continuous casting heat transfer heat removal simulation numerical methods

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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

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Recent progress on isospin breaking corrections and their impact on the muon g-2 value

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Chinese Physics C 2010年第6期34卷 712-717页

作者： Gabriel lópez Castro Departamento de Física CinvestavApartado Postal 14-74007000 MxicoD.F Mxico

We describe some recent results on isospin breaking corrections which are of relevance for predictions of the leading order hadronic contribution to the muon anomalous magnetic moment aμ^*** when using τ lepton data. When these corrections are applied to the new combined data on the π^±π^0 spectral function, the prediction for aμ^*** based on τ lepton data gets closer to the one obtained using e^＋e^- data.

关键词： isospin breaking tau decays muon magnetic moment radiative corrections

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Effect of Zn binding to phytate and humic substances on its uptake by wheat(Triticum durum l.)as affected by carbonates and Fe oxides

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Pedosphere 2022年第6期32卷 823-832页

作者： Ana m.GARCÍA-lÓpez Ramiro RECENA Antonio DElGADO Department of Agronomy ETSIAUniversity of SevilleSeville 41013(Spain)

Although complexation with soil organic matter may improve zinc(Zn)bioavailability to plants,the effect of Zn sorbent surface on the use of complexed Zn by plants remains *** objective of this research was to elucidate how Zn complexation with humic substances(Hs)and phytate affects the uptake of Zn by wheat plants depending on the main sorbent surface in growth media,i.e.,carbonates and Fe *** this end,two pot experiments were performed,one using Fe oxide-coated siliceous as the siliceous growth medium sand and the other using a mixture of calcareous sand and siliceous sand as the calcareous growth *** experiment involved three Zn sources,Zn-Hs complex,Zn phytate,and ZnsO_(4).All sources were applied with surface irrigation at two Zn rates(0.25 and 2 mg kg^(-1) growth medium).The Zn-Hs complex significantly increased Zn uptake by plants in both media,relative to the other two Zn sources,but no significant difference was observed between Zn phytate and ZnsO_(4).In the calcareous medium,Zn-Hs complex and Zn phytate resulted in significantly higher dry biomass yields of wheat than ZnsO_(4).In the siliceous medium,spike and shoot dry biomass yields with Zn-Hs complex at the low rate and Zn phytate at both rates were not significantly different from those with ZnsO_(4) at the high *** harvest,approximately 50%of the Zn applied as Zn-Hs complex remained extractable by diethylenetriaminepentaacetic acid(DTPA),while this proportion was less than 20%for the other Zn ***,Zn-Hs complex and Zn phytate are sources of available Zn for plants,and they are more effective than ZnsO_(4) in increasing plant growth,particularly when carbonates are the main Zn sorbent surface.

关键词： calcareous growth medium micronutrient organic matter organic phosphorus Zn availability Zn deficiency Zn sorbent surface Zn source

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