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Journal of Semiconductors 2022年第2期43卷 66-73页

作者： L.Castañeda sección de estudios de posgrado e Investigación de la escuela Superior de Medicina Instituto Politécnico NacionalPlan de San Luis y Díaz Mirón s/nCasco de Santo TomásCiudad de MéxicoA.P.11340México

Highly transparent conductive stoichiometric nanocrystalline stannic oxide coatings were deposited onto Corning®eAGLe XG®slim glass *** each coating,it was deposited for various concentrations in the aerosol solution with the substrate temperature maintained at 623.15 K by an ultrasonic spray pyrolysis(USP)*** was em-ployed both as the solution carrier in addition to aerosol directing gas,maintaining its flow rates at 3500.0 and 500.0 mL/min,*** coatings were polycrystalline,with preferential growth along the stannic oxide(112)plane,irrespective of the molarity content in the spray *** coating prepared at 0.2 M,a concentration in the aerosol solution,showed an average transmission of 60%in the visible light region spectrum with a maximum conductivity of 24.86 S/*** coatings deposited exhibited in the general photoluminescence spectrum emission colors of green,greenish white,and bluish white calculated on the intensities of the excitonic and oxygen vacancy defect level emissions.

关键词： stannic oxide coatings ultrasonic spray pyrolysis

Polyphenols as potential enhancers of stem cell therapy against neurodegeneration

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neural Regeneration Research 2022年第10期17卷 2093-2101页

作者： Diana Rodríguez-Vera Antonio Abad-García nancy Vargas-Mendoza Rodolfo Pinto-Almazán eunice D.Farfán-García José A.Morales-González Marvin A.Soriano-Ursúa sección de estudios de posgrado e Investigación.escuela Superior de Medicina Instituto Politécnico NacionalMéxico CityMéxico Unidad de Investigación Hospital Regional de Alta Especialidad IxtapalucaCarretera Federal México-Puebla km 34.5State of MéxicoMéxico

The potential of polyphenols for treating chronic-degenerative diseases(particularly neurodegenerative diseases)is ***,the selection of the best polyphenol for each treatment,the mechanisms by which they act,and their efficacy are frequently *** this review,the basics and the advances in the field,as well as suggestions for using natural and synthetic polyphenols alone or in a combinatorial strategy with stem cell assays,are compiled and ***,stem cells exhibit several responses when polyphenols are added to their environment,which could provide us with knowledge for advancing the elucidation of the origin of *** also,polyphenols are being included in the innovative strategies of novel therapies for treating neurodegenerative diseases as well as metabolic diseases related to *** this regard,flavonoid compounds are suggested as the best natural polyphenols due to their several mechanisms for acting in ameliorative effects;but increasing reports are involving other *** if some facts limiting bioactivity prevent them from conventional use,some natural polyphenols and derivatives hold the promise for being improved compounds,judged by their induced *** current results suggest polyphenols as enhancers of stem cell therapy against the targeted diseases.

关键词： Alzheimer’s disease chronic degenerative diseases combinatorial therapy metabolism neurodegenerative diseases neuronal damage neuroprotection Parkinson’s disease polyphenols stem cell assays

Insecticidal effect of Green Bimetallic nanoparticles from Crotalaria longirostrata on Cotton Mealybug,Phenacoccus solenopsis

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Journal of Renewable Materials 2022年第10期10卷 2543-2552页

作者： Vianey Mendez-Trujillo Benjamín Valdez-Salas Mario Curiel-Alvarez ernesto Beltran-Partida Arnoldo Alfaro-Corres esaúRuiz-Sanchez Gerardo Bautista-Trujillo Olivia Tzintzun Camacho Onecimo Grimaldo-Juarez Carlos Ceceña-Duran Carlos Ail-Catzin Daniel González-Mendoza Facultad de Medicina de la Universidad Autónoma de Baja California Dr.Humberto Torres Sanginés S/NCentro CívicoMexicaliBaja CaliforniaMéxico Instituto de Ingeniería de la Universidad Autónoma de Baja California Calle de la Normal S/N y Boulevard Benito JuárezMexicaliBaja CaliforniaMéxico Instituto Tecnológico de Conkal División de Estudios de Posgrado e InvestigaciónAntigua Carretera Mérida-MotulConkalYucatánMéxico Facultad de Medicina Veterinaria y Zootecnia de la Universidad Autónoma de Chiapas ChiapasMéxico Universidad Autónoma de Baja California Instituto de Ciencias AgrícolasBaja CaliforniaMéxico

The present study was conducted to evaluate the impact of bimetallic nanoparticles(nPs)of copper(Cu)and zinc(Zn)from Crotalaria longirostrata on the insect mortality and cell viability of Phenacoccus *** biosynthesis of bimetallic nanoparticles(Cu/Zn-nPs)from *** was confirmed by the presence of a single peak around 378 *** hydrodynamic diameter of the Cu/Zn nanoparticles varied from 59 to 119 nm and their zeta potential was found to be−30.90 *** eDX analysis showed a strong signal for Cu and Zn(8 and 8.6 keV,respectively).The Cu/Zn-nPs showed an effective insecticide activity against *** with 63%of insect mortality after 96 h ***,further studies about nanotoxicity of Cu/Zn-nPs from *** are needed to reveal the exact mechanism of nanoparticles toxicity in insects.

关键词： Phytonanoparticles chipilin biocontrol agronanotechnology

HP0953-hypothetical virulence factor overexpresion and localization during Helicobacter pylori infection of gastric epithelium

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World Journal of Gastroenterology 2022年第29期28卷 3886-3902页

作者： nancy K Arteaga-Resendiz Gerardo e Rodea Rosa María Ribas-Aparicio Alma L Olivares-Cervantes Juan Arturo Castelán-Vega Joséde Jesús Olivares-Trejo Sandra Mendoza-elizalde edgar O López-Villegas Christian Colín Pamela Aguilar-Rodea Alfonso Reyes-López Marcela Salazar García norma Velázquez-Guadarrama Laboratorio de Investigación en enfermedades Infecciosas Hospital Infantil de México Federico GómezMexico City 06720Mexico posgrado en Biomedicina y Biotecnología Molecular Laboratorio de Producción y Control de BiológicosEscuela Nacional de Ciencias BiológicasInstituto Politécnico NacionalMexico City 11340Mexico Laboratorio de Adquisición de Hierro Universidad Autónoma de la Ciudad MéxicoPosgrado Ciencias GenómicaMexico City 03100Mexico Laboratorio Central de Microscopía Escuela Nacional de Ciencias BiológicasInstituto Politécnico NacionalMexico City 11340Mexico Centro de estudios económicos y sociales en salud Hospital Infantil de México Federico GómezMexico City 06720Mexico Laboratorio de Investigación en Biología del desarrollo y Teratogénesis experimental Hospital Infantil de México Federico GómezMexico City 06720Mexico

BACKGROUnD The high prevalence and persistence of Helicobacter pylori(H. pylori) infection, as well as the diversity of pathologies related to it, suggest that the virulence factors used by this microorganism are varied. Moreover, as its proteome contains 340hypothetical proteins, it is important to investigate them to completely understand the mechanisms of its virulence and survival. We have previously reported that the hypothetical protein HP0953 is overexpressed during the first hours of adhesion to inert surfaces, under stress conditions, suggesting its role in the environmental survival of this bacterium and perhaps as a virulence *** To investigate the expression and localization of HP0953 during adhesion to an inert surface and against gastric(AGS) *** expression analysis was performed for HP0953 during H. pylori adhesion. HP0953 expression at 0,3, 12, 24, and 48 h was evaluated and compared using the Kruskal-Wallis equality-of-populations rank test. Recombinant protein was produced and used to obtain polyclonal antibodies for immunolocalization. Immunogold technique was performed on bacterial sections during adherence to inert surfaces and AGS cells, which was analyzed by transmission electron microscopy. HP0953 protein sequence was analyzed to predict the presence of a signal peptide and transmembrane helices, both provided by the exPASy platform, and using the GLYCOPP platform for glycosylation sites. Different programs, via, I-TASSeR, RaptorX, and HHalign-Kbest, were used to perform three-dimensional *** HP0953 exhibited its maximum expression at 12 h of infection in gastric epithelium *** technique revealed HP0953 localization in the cytoplasm and accumulation in some peripheral areas of the bacterial body, with greater expression when it is close to AGS *** analysis revealed the presence of a signal peptide that interacts with the transmembrane region and then allows the release of the protein

关键词： Hypothetical protein HP0953 Adherence Helicobacter pylori Glycocalyx Virulence factor Persistence

Pulsatile electroosmotic flow of a Maxwell fluid in a parallel flat plate microchannel with asymmetric zeta potentials

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Applied Mathematics and Mechanics(english edition) 2018年第5期39卷 667-684页

作者： M.PeRALTA O.BAUTISTA F.MendeZ e.BAUTISTA seccion de estudios de posgrado e Investigacion eSIMe Azcapotzalco Instituto Politecnico NacionalCiudad de Mexico 02250Mexico Facultad de Ingeniería Universidad Nacional Autonoma de MexicoCiudad de Mexico 04510Mexico

The pulsatile electroosmotic flow （PeOF） of a Maxwell fluid in a parallel flat plate microchannel with asymmetric wall zeta potentials is theoretically analyzed. By combining the linear Maxwell viscoelastic model, the Cauchy equation, and the electric field solution obtained from the linearized PoissomBoltzmann equation, a hyperbolic par- tial differential equation is obtained to derive the flow field. The PeOF is controlled by the angular Reynolds number, the ratio of the zeta potentials of the microchannel walls, the electrokinetic parameter, and the elasticity number. The main results obtained from this analysis show strong oscillations in the velocity profiles when the values of the elas- ticity number and the angular Reynolds number increase due to the competition among the elastic, viscous, inertial, and electric forces in the flow.

关键词： pulsatile electroosmotic flow (PeOF) flat plate microchannel asymmetric zeta potential Maxwell fluid

Welding effect at the Heat Affected Zone by Joining a Gray Cast Iron with Stainless Steel e308-16

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Materials Sciences and Applications 2023年第6期14卷 336-345页

作者： Yajaira Curiel-Razo enrique Curiel-Reyna Minerva Robles-Agudo Alberto Lara-Guevara Ignacio Rojas-Rodríguez Facultad de estudios Superiores-Cuautitlán Universidad Nacional Autónoma de México Cuautitlán-Izcalli México División Industrial Universidad Tecnológica de Querétaro Querétaro México División de posgrado Facultad de Informática Universidad Autónoma de Querétaro Querétaro México

Different investigations of the union of dissimilar materials such as stainless steel and different castings have been carried out, but rapid cooling immediately after welding has not been considered, in this work it was investigated how rapid cooling affects the metallurgical microstructure and consequently the mechanical properties. The effect of welding parameters on the microstructure and mechanical properties of the joint between dissimilar metals, an e-308-16 austenitic stainless steel and Gray Cast Iron was also analyzed. Gray cast iron samples (GCI) were fabricated, welded and cooled. The main welding parameters studied in this work are the welding technique and the type of filler electrodes. Flux-coated electrode e-308-16 was applied for this different joint. An experimental study was carried out for the analysis of welded joints of similar and dissimilar steels. The microstructure of the welded joints was analyzed using an optical microscope, in the base metals, heat affected zone (HAZ) and filler metal. The mechanical properties of the welded joints were evaluated by Vickers microhardness and tensile strength tests. The hardness profile showed differences in hardness between the base metals, the heat affected zone and the filler metal. The metallurgical microstructures observed along the welded areas corresponded to the profile. The hardness differences determined the effect on the mechanical and metallurgical characteristics of the welded samples as a result of the cooling rate differences. This research work is important because it allows us to analyze the possibility of reworking pieces of dissimilar materials by welding or, failing that, to determine if this may or may not be possible.

关键词： Gray Iron Welding Hot Affected Zone Filler Metal Microstructure Dissimilar Metals

Biocompatibility and electrochemical evaluation of ZrO_(2) thin films deposited by reactive magnetron sputtering on MgZnCa alloy

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Journal of Magnesium and Alloys 2021年第6期9卷 2019-2038页

作者： Benjamín Millán-Ramos Daniela Morquecho-Marín Phaedra Silva-Bermudez David Ramírez-Ortega Osmary depablos-Rivera Julieta García-López Mariana Fernández-Lizárraga JoséVictoria-Hernández Dietmar Letzig Argelia Almaguer-Flores Sandra e.Rodil Instituto de Investigaciones en Materiales Universidad Nacional Autónoma de MéxicoCDMX 04510Mexico posgrado en Ciencia e Ingeniería de Materiales Universidad Nacional Autónoma de MéxicoCDMX 04510Mexico Unidad de Ingeniería de Tejidos Terapia Celular y Medicina RegenerativaInstituto Nacional de Rehabilitación Luis Guillermo IbarraCDMX 14389Mexico posgrado en Ciencias Médicas Odontológicas y de la SaludUniversidad Nacional Autónoma de MéxicoCDMX 04510Mexico Instituto de Ciencias Aplicadas y Tecnologia Universidad Nacional Autónoma de MéxicoCDMX 04510Mexico posgrado de Doctorado en Ciencias en Biomedicina y Biotecnología Molecular Escuela Nacional de Ciencias BiológicasInstituto Politécnico NacionalCDMX 11340Mexico Institute of Material and Process design Helmholtz-Zentrum GeesthachtMax-Planck-Strasse 1Geesthacht 21502Germany Magnesium Innovation Centre MagIC Helmholtz-Zentrum GeesthachtMax-Planck-Strasse 1Geesthacht 21502Germany Laboratorio de Biointerfases Facultad de OdontologíaDivisión de Estudios de Posgrado e InvestigaciónUniversidad Nacional Autónoma de MéxicoCDMX 04510Mexico

Biodegradable magnesium alloys are promising candidates for temporary fracture fixation devices in orthopedics;nevertheless,its fast degradation rate at the initial stage after implantation remains as one of the main challenges to be ***_(2)-based coatings to reduce the degradation rate of the Mg-implants are an attractive solution since they show high biocompatibility and *** this work,the degradation,cytotoxicity,and antibacterial performance of ZrO_(2)thin films deposited by magnetron sputtering on a Mg-Zn-Ca alloy was ***-term degradation of ZrO_(2)-coated and uncoated samples was assessed considering electrochemical techniques and H_(2)evolution(gas chromatography).Additionally,long term degradation was assessed by mass-loss *** results showed that a 380 nm ZrO_(2)coating reduces the degradation rate and H_(2)evolution of the alloy during the initial 3 days after immersion but allows the degradation of the bare alloy for the *** ZrO_(2)coating does not compromise the biocompatibility of the alloy and permits better cell adhesion and proliferation of mesenchymal stem cells directly on its surface,in comparison to the bare ***,the ZrO_(2)coating prevents the adhesion and biofilm formation of ***.

关键词： Zirconium dioxide Magnetron sputtering Short-term degradation H_(2)evolution

A Comparison between Theoretical and experimental Coverage Analysis in 3G Cellular networks

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International Journal of Communications, network and System Sciences 2012年第3期5卷 147-153页

作者： Jazmín Ponce-Rojas Mariana eslava-Gutierrez Montserrat Jiménez-Licea Sergio Vidal-Beltrán sección de estudios de posgrado e Investigación ESIME Zac.-IPN México D.F. México

This paper shows a comparison between theoretical and experimental coverage analysis. Theoretical work is based on Okumura-Hata propagation model, which are compared with the measured data obtained through an experimental analysis en México City. It is important because all the network designers and managers have to take in account how the signals will arrive to the mobile devices. If they know it, they can install nodes B (base stations) in the better place in the area in order to take advantage of the power radiated by the antenna.

关键词： WCDMA Okumura-Hata Propagation Analysis

Probabilistic Model of Cumulative Damage in Pipelines Using Markov Chains

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Journal of Applied Mathematics and Physics 2020年第4期8卷 620-642页

作者： Francisco Casanova-del-Angel esteban Flores-Méndez Karina Guadalupe Cortes-Yah sección de estudios de posgrado e Investigación. escuela Superior de Ingeniería y Arquitectura Unidad Profesional ALM Instituto Politécnico Nacional Ciudad de México Mexico

This paper presents a probabilistic model of cumulative damage based on Markov chains theory to model propagation of internal corrosion depth localized in a hydrocarbons transport pipeline. The damage accumulation mechanism is unit jump type, depending on the state. It uses a shock model based on Bernoulli trials and probabilities to remain in the same state or the next one. Data are adjusted to Lognormal distribution and proven with a Kolmogórov-Smirnov test. The vector obtained from multiplying the initial state vector with the transition matrix was developed and the system of equations to find each transition probability with a single inspection report was solved. In order to calculate propagation of internal corrosion after inspection, an exponential equation was proposed and a parameter was adjusted to the data. Time to expected failure was obtained by adding the time expected in each damage state. each time step was adjusted to real time.

关键词： Localized Corrosion Cumulative Damage Failure Pipelines Markov Chains

Fixed Dose Combination of Magaldrate Plus Domperidone Is More effective than Domperidone Alone in the Treatment of Patients with Gastroesophageal Reflux Symptoms: A Randomized Double-Blind Study

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Pharmacology & Pharmacy 2014年第2期5卷 216-223页

作者： Shendel nyx Rodríguez-Sánchez Héctor Isaac Rocha-González Cecilia Fernández del Valle-Laisequilla Juan Rodríguez-Silverio Francisco Javier Flores-Murrieta Juan Gerardo Reyes-García Productos Medix S.A. de C.V. México City Mexico sección de estudios de posgrado e Investigación Escuela Superior de Medicina del Instituto Politécnico Nacional Mexico City Mexico sección de estudios de posgrado e Investigación Escuela Superior de Medicina del Instituto Politécnico Nacional Mexico City Mexico Instituto nacional de enfermedades Respiratorias Secretaría de Salud Mexico City Mexico

Gastroeophageal reflux is a condition in which the acidified liquid content of the stomach backs up into the esophagus. The antiacid magaldrate and prokinetic domperidone are two drugs clinically used for the treatment of gastroesophageal reflux symptoms. However, the evidence of a superior effectiveness of this combination in comparison with individual drugs is lacking. A double-blind, randomized and comparative clinical trial study was designed to characterize the efficacy and safety of a fixed dose combination of magaldrate (800 mg)/domperidone (10 mg) against domperidone alone (10 mg), in patients with gastroesophageal reflux symptoms. One hundred patients with gastroesophageal reflux diagnosed by Carlsson scale were randomized to receive a chewable tablet of a fixed dose of magaldrate/domperidone combination or domperidone alone four times each day during a month. Magaldrate/domperidone combination showed a superior efficacy to decrease global esophageal (pyrosis, regurgitation, dysphagia, hiccup, gastroparesis, sialorrhea, globus pharyngeus and nausea) and extraesophageal (chronic cough, hoarseness, asthmatiform syndrome, laryngitis, pharyngitis, halitosis and chest pain) reflux symptoms than domperidone alone. In addition, magaldrate/domperidone combination improved in a statistically manner the quality of life of patients with gastroesophageal reflux respect to monotherapy, and more patients perceived the combination as a better treatment. Both treatments were well tolerated. Data suggest that oral magaldrate/domperidone mixture could be a better option in the treatment of gastroesophageal reflux symptoms than only domperidone.

关键词： Antiacid Domperidone Gastroesophageal Reflux Magaldrate Prokinetic