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A New Analysis of an Implicit Mimetic Scheme for the Heat Equation

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Journal of Applied Mathematics and Physics 2023年第3期11卷 841-857页

作者： Mariela Castillo nava Juan manuel Guevara-Jordan Universidad Metropolitana Caracas Venezuela Universidad Central de Venezuela Caracas Venezuela

A mimetic finite difference scheme for the transient heat equation under Robin’s conditions is presented. The scheme uses second order gradient and divergence mimetic operators, on a staggered grid, to approximate the space derivatives. The temporal derivative is replaced by a first order backward difference approximation to obtain an implicit formulation. The resulting scheme contains nonstandard finite difference stencils. An original convergence analysis by the matrix’s method shows that the proposed scheme is unconditionally stable. A comparative study against standard finite difference schemes, based on central difference or first order one side approximations, reveals the advantages of our scheme without being its implementation more expensive or difficult to achieve.

关键词： Mimetic Finite Difference Robin’s Condition Implicit Stable Transient Heat

Alzheimer’s disease and type 2 diabetes mellitus:Pathophysiologic and pharmacotherapeutics links

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World Journal of Diabetes 2021年第6期12卷 745-766页

作者： Milagros Rojas Mervin Chávez-Castillo Jordan Bautista Ángel Ortega manuel nava Juan Salazar Edgar Díaz-Camargo Oscar Medina Joselyn Rojas-Quintero Valmore Bermúdez Endocrine and Metabolic Diseases Research Center School of MedicineUniversity of ZuliaMaracaibo 4004Venezuela Universidad Simón Bolívar Facultad de Ciencias Jurídicas y SocialesCúcuta 540006Colombia Pulmonary and Critical Care Medicine Department Brigham and Women's HospitalHarvard Medical SchoolBostonMA 02155United States Universidad Simón Bolívar Facultad de Ciencias de la SaludBarranquilla 080001Colombia

At present,Alzheimer’s disease(AD)and type 2 diabetes mellitus(T2DM)are two highly prevalent disorders worldwide,especially among elderly individuals.T2DM appears to be associated with cognitive dysfunction,with a higher risk of developing neurocognitive disorders,including *** diseases have been observed to share various pathophysiological mechanisms,including alterations in insulin signaling,defects in glucose transporters(GLUTs),and mitochondrial dysfunctions in the ***,the aim of this review is to summarize the current knowledge regarding the molecular mechanisms implicated in the association of these pathologies as well as recent therapeutic *** this context,the hyperphosphorylation of tau and the formation of neurofibrillary tangles have been associated with the dysfunction of the phosphatidylinositol 3-kinase and mitogen-activated protein kinase pathways in the nervous tissues as well as the decrease in the expression of GLUT-1 and GLUT-3 in the different areas of the brain,increase in reactive oxygen species,and production of mitochondrial alterations that occur in *** findings have contributed to the implementation of overlapping pharmacological interventions based on the use of insulin and antidiabetic drugs,or,more recently,azeliragon,amylin,among others,which have shown possible beneficial effects in diabetic patients diagnosed with AD.

关键词： Alzheimer’s disease Type 2 diabetes mellitus Oxidative stress Islet amyloid polypeptide Glucagon-like peptide 1 Cognitive dysfunction Hypoglycemic agents

The Tesistan, Mexico earthquake (M_w 4.9) of 11 May 2016: seismic-tectonic environment and resonance vulnerability on buildings

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Earthquake Engineering and Engineering Vibration 2019年第3期18卷 579-595页

作者： Alejandro Ramírez-Gaytán Adolfo Preciado William L. Bandy Edilson F. Salazar-Monroy Miguel A. jaimes Leonardo Alcantara Departamento de Ciencias Computacionales Centro Universitario de Ciencias Exactas e Ingeniería Universidad de Guadalajara Boulevard Marcelino García Barragán # 1421 44430 Guadalajara Jalisco México Departamento del Hábitat y Desarrollo Urbano Instituto Tecnológico y de Estudios Superiores de Occidente (ITESO). Periférico Sur Manuel Gómez Morin 8585 45604 Tlaquepaque Jalisco México Instituto de Geofísica Universidad Nacional Autónoma de México Circuito Interior Ciudad Universitaria Del. Coyoacán 04510 México Programa de Posgrado en Ciencias de la Tierra Universidad Nacional Autó noma de Mé xico Circuito Interior Ciudad Universitaria Del. Coyoacá n 04510 Mé xico Instituto de Ingenieria Universidad Nacional Autónoma de México Circuito Interior Ciudad Universitaria Del. Coyoacán 04510 México

To highlight the importance of small earthquakes in seismic hazard, a study of the 11 May 2016, Mw 4.9, Tesistan, Mexico earthquake is presented. Due to the close proximity of the event to the city, accelerations were considerably higher than those caused by historical severe earthquakes (6.0 < Mw < 8.2). This paper addresses two objectives related to the Tesistan event: the fi rst is to estimate the focal mechanism solution in order to place the event in the context of the tectonic environment of this area. The second is focused on a vulnerability evaluation of buildings that suff ered resonance. Several building′s typologies with variations in construction system and height are assessed in terms of resonance with the structural and soil periods. The results show that around the Zapopan station, strong damage is expected in intermediate to high-rise buildings (12-30 m) with moment resistant frame systems and in reinforced concrete shear walls. Masonry structures around this station may not present resonance. In contrast, in the surroundings of the Guadalajara station, all intermediate height buildings from 9 to 21 m may present resonance.

关键词： Tesistan earthquake seismicity of Guadalajara site eff ects structural vulnerability

Avocado Nutritional Diagnosis （Persea americana Mill.）＂Hass＂, Soil Fertility and Water Quality in Ocuituco, Morelos

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Journal of Chemistry and Chemical Engineering 2013年第11期7卷 1068-1073页

作者： Hector Sotelo-nava Oscar Gabriel Villegas-Torres Martha Lilia Dominguez-Patint Elias Hernfindez Castro Agustin Damian nava Antonio Rodrlguez-Martmez Carlos manuel Acosta-Duran Maria Andrade-Rodriguez Iran Alia-Tej acal Faculty of Agricultural Sciences Universidad Aut6noma del Estado de Morelos Cuernavaca 62209 Mexico Faculty of Chemical Sciences and Engineering Universidad Aut6noma del Estado de Morelos Cuernavaca 62209 Mexico Unit of Agricultural and Environmental Sciences Universidad Autonoma de Guerrero Guerrero 39196 Mexico Engineering and Applied Science Research Center Universidad Autonoma del Estado de Morelos Cuernavaca 62209 Mexico

Morelos is the fourth in area cultivated and production volume of avocado. Of the 13 municipalities where it is farmed, Ocuituco represents 43.51% and Tetela del Volain 27.53%. Despite being one of the main fruit species in Morelos, no information related to the fertility of the soil where it is grown, the quality of water available for irrigation and nutritional status of this important fruit for the state. The study was conducted in the municipality of Ocuituco which identified three agro-habitats taking into account climate, landform, soil type and altitude. In each agro-habitat were carried out soil sampling to determine the physical and chemical characteristics based on the Mexican Official Standard NOM-021-SEMARNAT-2000, the chemical quality of water for irrigation as described by Richards （1954） and crop nutrient status of avocado ＂Hass＂ according to the methodology described by Maldonado （2002）. The soils had different physical and chemical characteristics, as well as the nutritional status of avocado trees in the three agro-habitats. The trees had excessive concentration of CI, Cu and Zn. Indices of optimal percentage deviation expressed different nutritional requirements. The water used for irrigation was of low salinity and sodium content, so it can be used without restrictions.

关键词： Soil fertility water quality nutrients Hass.

Importance of the Role of Gibberellic Acid and Potassium Nitrate in Seed Germination Habanero

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Journal of Chemistry and Chemical Engineering 2013年第2期7卷 145-153页

作者： Oscar Gabriel Villegas-Torres Martha Ldla Dommguez-Patino Carlos manuel Acosta-Durfin HectorSotelo-nava Jose Daniel Lopez-Gomez Guillermo Flores-Sfinchez Faculty of Agricultural Sciences University of the State of Morelos Cuernavaca 62209 Mexico Faculty of Chemical Sciences and Engineering University of the State of Morelos Cuernavaca 62209 Mdxico Research Center for Applied Science and Engineering University of the State of Morelos Cuernavaca 62209 M~xico

The habanero chili （Capsicum chinense Jacq.） is a species of great demand in the domestic and international markets. One problem in the cultivation is low percentage of seed germination. There is little information on the use of promoters and imbibition time to increase this parameter, without compromising the quality of seedlings. In this context, authors assessed the independent effect of GAs （gibberellic acid） and KNOs at concentrations of 0, 100, 200, 300, 400 and 500 mg·L1. Seeds without preconditioning were the witness. The experimental unit was a Petri dish with 50 seeds on filter paper placed equidistant. There were three replicates per treatment and the experimental design was randomized complete block. Imbibition time was 24 h. The experimental units were kept in an incubator at 22 ± 2 ℃. From the time of planting and for periods of 24 h for 14 d, experimental units were reviewed to determine the time at the beginning of germination and the total cumulative percentage. The authors also determined the number of normal and abnormal seedlings, the length of hypocotyl and radicle, weight of fresh and dry matter of seedlings. On the fifth day after sowing in vitro, concentrations of 500 mg·L^-1 of GAs, 300 and 400 mg·L^-1 KNO3, increased 208% the percentage of seed germination of habanero chile. On day 14 after sowing in vitro concentrations of 500 mg·L^-1 GA3, 300 and 400 mg·L^-1 KNO3, increased 23% normal seedlings and 40% dry matter thereof, with respect to seeds obtained without preconditioning. Unconditioned seeds before sowing produced 125% more seedlings.

关键词： Imbibition hypocotyl radicle dry matter fresh matter.

Cerebral dopamine neurotrophic factor transfection in dopamine neurons using neurotensin-polyplex nanoparticles reverses 6-hydroxydopamine-induced nigrostriatal neurodegeneration

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Neural Regeneration Research 2022年第4期17卷 854-866页

作者： manuel A.Fernandez-Parrilla David Reyes-Corona Yazmin M.Flores-Martinez Rasajna Nadella Michael J.Bannon Lourdes Escobedo Minerva Maldonado-Berny Jaime Santoyo-Salazar Luis O.Soto-Rojas Claudia Luna-Herrera Jose Ayala-Davila Juan A.Gonzalez-Barrios Gonzalo Flores Maria E.Gutierrez-Castillo Armando JEspadas-Alvarez Irma A.Martínez-Dávila Porfirio nava Daniel Martinez-Fong Departamento de Fisiología Biofísica y NeurocienciasCentro de Investigación y de Estudios AvanzadosCiudad de MéxicoMéxico Programa Institucional de Biomedicina Molecular Escuela Nacional de Medicina y HomeopatíaInstituto Politécnico NacionalCiudad de MéxicoMéxico Department of Biosciences IIIT-SrikakulamRajiv Gandhi University of Knowledge Technologies(RGUKT)Andhra PradeshIndia Department of Pharmacology Wayne State University School of MedicineDetroitMIUSA Departamento de Física Centro de Investigación y de Estudios AvanzadosCiudad de MéxicoMéxico Facultad de Estudios Superiores Iztacala Universidad Nacional Autónoma de MéxicoTlalnepantla de BazEdo.de MéxicoMéxico Departamento de Fisiología Escuela Nacional de Ciencias BiológicasCiudad de MéxicoMéxico Laboratorio de Medicina Genómica Hospital Regional“1°de Octubre”ISSSTECiudad de MéxicoMéxico Laboratorio de Neuropsiquiatría Instituto de FisiologíaBenemérita Universidad Autónoma de PueblaPueblaPueblaMéxico Departamento de Biociencias e Ingeniería Centro Interdisciplinario de Investigaciones y Estudios sobre Medio Ambiente y DesarrolloInstituto Politécnico NacionalCiudad de MéxicoMéxico Programa de Nanociencias y nanotecnología Centro de Investigación y de Estudios AvanzadosCiudad de MéxicoMéxico

Overexpression of neurotrophic factors in nigral dopamine neurons is a promising approach to reverse neurodegeneration of the nigrostriatal dopamine system,a hallmark in Parkinson's *** human cerebral dopamine neurotrophic factor(h CDNF)has recently emerged as a strong candidate for Parkinson's disease *** study shows that h CDNF expression in dopamine neurons using the neurotensinpolyplex nanoparticle system reverses 6-hydroxydopamine-induced morphological,biochemical,and behavioral *** independent electron microscopy techniques showed that the neurotensin-polyplex nanoparticles containing the h CDNF gene,ranging in size from 20 to 150 nm,enabled the expression of a secretable h CDNF in *** injection in the substantia nigra compacta on day 21 after the 6-hydroxydopamine lesion resulted in detectable h CDNF in dopamine neurons,whose levels remained constant throughout the study in the substantia nigra compacta and *** with the lesioned group,tyrosine hydroxylase-positive(TH^(+))nigral cell population and TH+fiber density rose in the substantia nigra compacta and striatum after h CDNF *** increase inβIII-tubulin and growth-associated protein 43 phospho-S41(GAP43 p)followed TH^(+)cell recovery,as well as dopamine and its catabolite *** reversal(80%)of drugactivated circling behavior and full recovery of spontaneous motor and non-motor behavior were ***-derived neurotrophic factor recovery in dopamine neurons that also occurred suggests its participation in the neurotrophic *** findings support the potential of nanoparticle-mediated h CDNF gene delivery to develop a disease-modifying treatment against Parkinson's *** Institutional Animal Care and Use Committee of Centro de Investigación y de Estudios Avanzados approved our experimental procedures for animal use(authorization No.162-15)on June 9,2019.

关键词： axonal growth brain-derived neurotrophic factor gene delivery nanoparticles neuritogenesis neuronal cytoskeleton neuroregeneration neurorestoration neurotrophic therapy Parkinson's disease reinnervation substantia nigra

Epidemiology of Fingertip Injuries at South Central Hospital Petróleos Mexicanos “Pemex” with a Review of the Literature

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Journal of Biosciences and Medicines 2023年第6期11卷 182-195页

作者： Fernando Barbosa-Villarreal Cuahutémoc Márquez-Espriella Erika Barlandas-Quintana Ana Priscila Campollo-López Mauricio Gutiérrez-Álvarez Carlos Emiliano García-Córdova Jesús Ricardo García-Corral Alfredo Chama-Naranjo Ricardo Alberto Pulido-López Patricia Llizette López-Medellín Edgar Alan Guillen-Martínez Jonathan Steve Rodríguez-Alaníz Edwing Michel jaimes-Duran Carlos manuel Cortes-Aguilar Mauro Garibaldi-Bernot Omar Alberto Pérez-Benítez Miguel Eduardo Marín-Canto Luis Arturo Herrera-Lozano Héctor manuel Suarez-Ortega Alejandro Cruz-Zarate Department of Plastic and Reconstructive Surgery Hospital Central Sur Petróleos Mexicanos Mexico City Mexico

Background: The hand is an essential component for performing our daily tasks;as a result, injuries to the fingertip are frequently seen. Accurate evaluation and treatment of fingertip injuries are essential to avoiding long-term disability, job loss and psychological issues. No matter the injury classification system, maintaining finger length, regaining sensation, and improving appearance are the three main objectives of treatment. The objective of this research was to outline the epidemiology of fingertip injuries treated between 2021 and 2022 at a highly specialized referral hospital in Mexico City. Methodology: This investigation is cross-sectional, retrospective, and observational. From January 2021 to December 2022, 60 patients with a diagnosis of fingertip injury from the South Central Hospital “Pemex” were included. The descriptive statistical analysis was performed using SPSS29. Results: 60 patients were included, 27 (45%) were women and 33 (55%) were men. Allen’s classification was able to classify only 19 patients, of which 18 (94.7%) had a type 1 classification and one (5.26%) had a type 2 classification. 10% of patients experienced complications, which included 2 patients with surgical site infections (3.3%), 3 patients with persistent pain (5%), and 1 patient (1.6%) with graft rejection. Conclusions: There are currently insufficient epidemiological data on hand and wrist injuries and its effects on labor in Mexico. Fingertip injuries require particular care in order to prevent complications and long-term damage. The creation of national registries could help with the creation of reference manuals for the care of hand and wrist injuries in our nation.

关键词： Fingertip Fingertip Injuries Epidemiology

Management of Complex Wounds with Dermal Substitute Assisted by a Negative Pressure System

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Modern Plastic Surgery 2023年第4期13卷 95-105页

作者： Cuahutémoc Márquez Espriella Ruiz Garza Jorge Gerardo Barbosa Villarreal Fernando Dávila Díaz Rodrigo Cuervo Vergara Marco Antonio Campollo López Ana Priscila Gutierrez Alvarez Mauricio Chama Naranjo Alfredo García Corral Jesús Ricardo Pérez Benítez Omar Alberto Pulido López Ricardo Alberto jaimes Duran Edwing Michel Garibaldi Bernot Mauro Cortes Aguilar Carlos manuel García Córdova Carlos Emiliano Camacho Rodriguez Hayah Camacho Rodriguez Hayah Martinez Villalobos Claudia Nallely Ochoa Contreras Erick Cesar Randall Cruz Soto Herrera Lozano Luis Arturo Department of Plastic and Reconstructive Surgery Hospital Central Sur Petróleos Mexicanos Mexico City Mexico

Introduction: The standard treatment for complex wound care is autografting. The advent of dermal substitutes has provided a novel tool for the preparation of the bed to be grafted. However, most types of dermal matrices require the application of a skin graft a second time. Currently, other strategies have been developed to improve the vascularization process, such as negative pressure wound therapy (NPWT), which has been reported to reduce the time required for vascular growth and dermal matrix integration and thus achieve a shorter waiting period for autologous graft application. The present study aims to evaluate the effectiveness and safety of dermal matrix management associated with NPWT in the treatment of complex wounds. Methods: Seven patients with a diagnosis of complex wounds were enrolled in this study between July 1, 2015, and June 31, 2016. After debridement and having an adequate wound bed, patients who met the criteria for the application of combined therapy were treated with dermal substitutes and a negative pressure system. The percentage of graft integration into the wound bed, complications, length of hospital stay, and duration of therapy were analyzed. Results: The mean age was 42.5 ± 16 (39 - 54) years old;three women and four men were included in the study. The approximate size of skin loss was 120.7 ± 75 cm2 (25 - 250 cm2). The combined therapy of dermal matrix plus NPWT was instituted in all cases for a period of 14 days. There were no complications, with 100% graft integration in 6 of 7 cases. Patients were discharged after a mean hospital stay of 5.4 days. Conclusions: This study demonstrates that the utilization of combined dermal matrix plus NPWT therapy can be performed safely and effectively in patients with complex wounds with low complication rates and a short hospital stay.

关键词： Negative Pressure Wound Therapy Complex Wound Dermal Matrix Wound Therapy

Synthesis of Solid Acid Catalysts Based on TiO2- SO42-and Pt/TiO2- SO42-Applied in n-Hexane Isomerization

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Open Journal of Metal 2013年第3期3卷 34-44页

作者： Juan manuel Hernández Enríquez Luz Aracely Cortez Lajas Ricardo García Alamilla Estefanía ángeles San Martín Pedro García Alamilla Edward Brent Handy Guadalupe Cárdenas Galindo Luz Arcelia García Serrano CIEP Facultad de Ciencias Químicas Universidad Autónoma de San Luis Potosí Av. Dr. Manuel Nava #6 Zona Universitaria 78210 San Luis Potosí San Luis Potosí México Instituto Politécnico Nacional Centro Interdisciplinario de Investigaciones y Estudios sobre Medio Ambiente y Desarrollo 30 de Junio #1520 Barrio La Laguna Ticomán 07340 México D.F. México Instituto Tecnológico de Cd. Madero División de Estudios de Posgrado e Investigación Juventino Rosas y Jesús Urueta S/N Col. Los Mangos 89440 Cd. Madero Tamaulipas México Universidad Juárez Autónoma de Tabasco División Académica de Ciencias Agropecuarias Avenida Universidad S/N Zona Cultura Colonia Magisterial 86040 Villahermosa Tabasco México

The physicochemical properties and catalytic activity of pure and sulfated titanium oxide (TiO2 and ) is described in this work. Titanium hydroxide synthesized by the sol-gel method was impregnated with a 1 N H2SO4 solution, varying amount of sulfate ions () in the range from 10 to 20 wt%. Pure and modified hydroxides were calcined at 500°C for 3 h and then characterized by TGA-DTG, XRD, BET, FT-IR, potentiometric titration with n-butylamine and 2-propanol dehydration. Catalytic activity of materials was tested in the n-hexane isomerization at 350°C. The results showed that TiO2 and mainly developed anatase phase. All have acceptable specific surface area (95-105 m2/g). Potentiometric titration with n-butylamine revealed that showed higher acidity (430-530 mV) than compared to pure TiO2 (﹣15 mV), indicating that this oxide only has weak acidity. The results showed good relationship between acidity determined by potentiometric titration with n-butylamine and the catalytic activity evaluated by 2-propanol dehydration and n-hexane isomerization. Titanium oxide with 20 wt% ofions was the material that demonstrated the highest catalytic activity for both reactions.

关键词： Acid Catalysts Sulfated Titanium Oxide Physico-Chemical Properties n-Hexane Isomerization