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Water Quality Assessment of Jose Antonio Alzate Dam, the lerma River and Its Tributaries in the State of Mexico, Mexico

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Journal of Environmental Protection 2012年第8期3卷 878-888页

作者： Icela Barceló-Quintal edgar lópez-galván Hugo Solís-Correa Eloisa Domínguez-Mariani Sergio Gómez-Salazar área de Química y Fisicoquímica Ambiental Depto de Ciencias Básicas División de Ciencias Básicas e Ingeniería UAM-Azcapot- zalco Ciudad de México D.F. México Departamento de Ingeniería Química Universidad de Guadalajara. Centro Universitario de Ciencias Exactas e Ingenierías Guadalajara Jalisco México

Water quality was evaluated at sites of the Jose Antonio Alzate Dam, the rivers lerma, Tejalpa and Temoaya in the State of Mexico, Mexico. The variables measured included pH, conductivity, temperature, dissolved oxygen (DO), ammonia, nitrates, sulfates, sulfides and metal concentrations (Cu and Pb). Chemical speciation for dissolved metals in the aqueous phase was obtained using measured concentrations and the software MInEQl+ (4.5);metal partition coefficients was also obtained using dissolved and particulate concentrations of metals. Hydraulic behavior of the studied water bodies was investigated and the fate of Cu and Pb ions was simulated. The simulation results indicate that the lerma River provides the majority of organic matter and metal contaminants as a result of a poor oxygen saturation velocity, and showed a slight improvement when the lerma River is subjected to its tributaries Tejalapa and Temoaya Rivers. Under the reducing conditions predominating along the dam and from the results of aqueous phase chemical speciation, it was found that sulfide metal-associated species are the ones that predominate. It was demonstrated that in general, the rivers Tejalapa and Temoaya presented the best water quality. The lerma River oxygen saturation improves after the rainy season, but it worsens during the dry season. Due to irregular topography, the small slope prevailing in the lerma River, and the almost nonexisting water flow, zones with different characteristics are formed within the dam. The sedimentation contributes in the generation of local eddies causing the existence of a small diffusive flow. The order of partition coefficient was Pb > Cu. Cu presented the highest risk levels in the dissolved phase.

关键词： Water Quality Copper lead Partition Coefficients Chemical Speciation

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A novel and Functional Artificial Bruch’s Membrane Made of Poly (ε-Caprolactone)/Gelatin for Retinal Pigment Epithelium Restoration

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Advances in Bioscience and Biotechnology 2024年第8期15卷 443-461页

作者： lópez Edith Silva-Bermudez Phaedra Gonzalez-Salinas Roberto Velasquillo Cristina Torres-Romero Abigail lópez-Colomé Ana María Pérez Armando Gina Prado-Prone edgar Ramos-Martínez Iván Ramos-Martínez Quiroz-Mercado Hugo Hernández-Zimbrón luis Fernando Instituto de Fisiologa Celular Universidad Nacional Autnoma de Mxico Ciudad de Mxico City Mxico Unidad de Ingeniería de Tejidos Terapia Celular y Medicina Regenerativa Instituto Nacional de Rehabilitación Luis Guiller-mo Ibarra Ibarra Ciudad de México México Departamento de Investigacin Asociacin Para Evitar la Ceguera Ciudad de Mxico Mxico Subdireccin de Investigacin Tecnolgica Instituto Nacional de Rehabilitacin Luis Guillermo Ibarra Ibarra Ciudad de Mxico Mxico Departamento de Biologa Celular y Tisular Facultad de Medicina Universidad Nacional Autnoma de Mxico Ciudad de Mxico Mxico Escuela de Ciencias Universidad Autnoma Benito Jurez de Oaxaca Oaxaca Mxico Departamento de Medicina y Zootecnia de Cerdos Facultad de Medicina Veterinaria y Zootecnia Universidad Nacional utnoma de Mxico Mxico laboratorio de Investigacion Interdisciplinaria rea de Optometria Escuela Nacional de Estudios Superiores Unidad Len Universidad Nacional Autnoma de Mxico Len Guanajuato Mxico laboratorio nacional de ptica de la Visin-Centro de Investigaciones en ptica Len Guanajuato Mxico

Purpose: The primary aim of this paper is to design, create, and improve functional and artificial Bruch’s membranes (BM) using bioengineering techniques, which can be applied in the treatment of maculopathies by supporting the growth and maintenance of retinal pigment epithelium (RPE) cells, thereby potentially enabling subretinal implantation in patients. Methods: We fabricated by electrospinning ultrathin 3D nanofibrous membranes from Polycaprolactone (PCl), and different concentrations of gelatin (5%, 15% and 30%). ARPE-19 cells were seeded onto these artificial membranes. MTT assays were performed in order to evaluate ARPE-19 cell viability and cytotoxicity. IF assays were realized to observe the ARPE-19 cells onto each membrane. Ultrastructure of the modified Bruch’s membrane and ARPE-19 morphology after 25 days of culture were studied with transmission and scanning electron microscopy. To evaluate expression changes in markers of ARPE-19 (RPE65 and ZO-1) qRT-PCR assays were realized. Data from three independent experiments were pooled and expressed as the mean SD. A confidence level of P 0.05 was considered to be statistically significant. Results ARPE-19 cells grew on PCl/Gelatin membranes mainly in PCl/30% gelatin combination, which had not cytotoxic effect. RPE65/cytokeratin-18/ and actin-positive ARPE-19 cells formed a correctly orientated monolayer of polygonal cells with morphological polarity. The apical cell surfaces exhibited abundant protruding microfolds. Moreover, zones of polygonal border look as if ARPE-19 cells fused among, suggesting the presence of tight junctions. The expression of RPE65 and ZO-1 was unchanged. Conclusions: PCl/30% Gelatine membranes may imitate the natural BM to such extent that they support RPE-cells and exhibited RPE-like morphology. The engineering of a human RPE monolayer with these artificial BM, emulating the in vivo retina, arouse their potential subretinal implantation in patients with wet age-related macular degene

关键词： Artificial Bruch’s Membrane Electrospinning ARPE-19 Cells Age-Related Macular Degeneration

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Venopulmonary ECMO Improved Hypoxemia and Supported the Right Ventricle in a Patient with Decompensated Eisenmenger Syndrome

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World Journal of Cardiovascular Surgery 2024年第1期14卷 7-19页

作者： Daniel Manzur-Sandoval Gian Manuel Jiménez-Rodríguez edgar García-Cruz Ramón Espinosa-Soto Erika Yamali Ramirez-Marcano Yessenia Máyory Téllez-lópez José luis Elizalde-Silva Gustavo Rojas-Velasco Cardiovascular Critical Care Unit Ignacio Ch&#225vez National Institute of Cardiology Mexico City Mexico Adult Congenital Heart Disease Unit Ignacio Ch&#225vez National Institute of Cardiology Mexico City Mexico Cardiology Department Ignacio Ch&#225vez National Institute of Cardiology Mexico City Mexico

Mechanical circulatory and/or respiratory assistance with extracorporeal membrane oxygenation (ECMO) has become a standard of care for patients with circulatory (venoarterial) and/or respiratory (venovenous) failure refractory to standard therapies. Adult patients with congenital heart disease are an increasingly recognized and growing population and include various groups, such as undiagnosed cases in childhood and palliated and/or corrected cases, which require subsequent care because of residual lesions, cardiac arrest/insufficiency, and arrhythmias, among other conditions. In addition, these patients are prone to developing pathologies that are typical of adulthood with a generally increased risk of morbidity and mortality because of their low reserves and organic damage associated with the underlying heart disease, which makes them candidates for ECMO. These patients represent an additional challenge in this therapy because malformations and the presence of a shunt can generally affect the usual cannulation methods and hemodynamic and oximetry monitoring. Thus, the configuration decision must be made on a case-by-case basis. Here, we present a cannulation method, venopulmonary artery ECMO, which provides hemodynamic and respiratory support, and may be ideal for patients with shunts and/or right ventricular dysfunction. To our knowledge, this is the first report of this configuration in patients with congenital heart diseases.

关键词： Eisenmenger Syndrome Venopulmonary Artery ECMO Refractory Hypoxemia Right Ventricular Dysfunction

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Kinetic analysis via mathematical modeling for ferrous iron oxidation in a class of SBR-type system

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Chinese Journal of Chemical Engineering 2019年第10期27卷 2472-2480页

作者： edgar nTec-Caamal Refugio Rodríguez-Vázquez luis GTorres-Bustillos Ricardo Aguilar-lópez Center for Research and Advanced Studies of the national Polytechnic Institute Av.Instituto Politécnico Nacional No.2508Colonia San Pedro ZacatencoC.P.07360 Ciudad de México D.F.Mexico Interdisciplinary Professional Unit of Biotechnology-national Polytechnic Institute(UPIBI-IPn) Acueducto s/nLa Laguna TicománGustavo A.Madero07340Ciudad de MéxicoMexico

This paper analyses the oxidation of ferrous iron via chemical and biological means in a class of Sequential Batch Reactors(SBR-type).For this,a kinetic model for the study of iron oxidation system is proposed,followed by a parametric sensitivity analysis and a bifurcation analysis,which allow selecting the most influential kinetic parameters in order to ensure a suitable prediction capacity of the mathematical *** system consists of two SBR bioreactors,the first being used to produce hydrogen peroxide(H2O2)that is fed to a second reactor where the iron oxidation is carried out by chemical–biological *** predictions were compared with experimental data for the production of H2O2 and for ferrous iron oxidation,finding suitable correlation coefficients(r2 n 0.98)for each state *** bifurcation analysis showed the trajectories of the main variables,such as,biomass,H2O2 and ferrous iron,under the change of the most influential kinetic *** analysis demonstrates the usefulness of the constructed model to predict the kinetic behaviour of the SBR-type process.

关键词： Bifurcation analysis Hydrogen peroxide Iron oxidation Modeling Simulation

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Effect of initial microstructure on austenite formation kinetics in high-strength experimental microalloyed steels

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International Journal of Minerals,Metallurgy and Materials 2015年第12期22卷 1304-1312页

作者： edgar lópez-Martínez Octavio Vázquez-Gómez Héctor Javier Vergara-Hernández Bernardo Campillo Faculty of Chemistry Metallurgical Engineering Department Autonomous National University of Mexico national Council for Science and Technology Metallurgy Science Postgraduate Programme Morelia Institute of Technology Institute of Physical Sciences Autonomous National University of Mexico

Austenite formation kinetics in two high-strength experimental microalloyed steels with different initial microstructures comprising bainite-martensite and ferrite-martensite/austenite microconstituents was studied during continuous heating by dilatometric analysis. Austenite formation occurred in two steps：（1） carbide dissolution and precipitation and （2） transformation of residual ferrite to austenite. Dilatometric analysis was used to determine the critical temperatures of austenite formation and continuous heating transformation diagrams for heating rates ranging from 0.03°C.s^-1 to 0.67°C.s^-1. The austenite volume fraction was fitted using the Johnson-Mehl-Avrami-Kolmogorov equation to determine the kinetic parameters k and n as functions of the heating rate. Both n and k parameters increased with increasing heat- ing rate, which suggests an increase in the nucleation and growth rates of austenite. The activation energy of austenite formation was determined by the Kissinger method. Two activation energies were associated with each of the two austenite formation steps. In the first step, the austenite growth rate was controlled by carbon diffusion from carbide dissolution and precipitation; in the second step, it was controlled by the dissolution of residual ferrite to austenite.

关键词： non-isothermal kinetics microalloyed steel austenite heating dilatometry

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Assessing above-ground biomass-functional diversity relationships in temperate forests in northern Mexico

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Forest Ecosystems 2021年第1期8卷 95-108页

作者： Benedicto Vargas-larreta Jorge Omar lópez-Martínez edgar J.González JoséJavier Corral-Rivas Francisco Javier Hernández Tecnológico nacional de México/Instituto Tecnológico de El Salto 34942 El SaltoDurangoMexico Cátedras CONACYT1582Av.Insurgentes SurCiudad de MéxicoMexico El Colegio de la Frontera Sur 77014ChetumalQuintana RooMexico Departamento de Ecología y Recursos naturales Facultad de CienciasUniversidad Nacional Autónoma de MéxicoCiudad de MéxicoMexico Facultad de Ciencias Forestales Universidad Juárez del Estado de DurangoRío Papaloapan y Blvd.Durango s/nCol.Valle del Sur34120 DurangoMexico

Background:Studies on the relationship between biodiversity and ecosystem productivity have suggested that species richness and functional diversity are the main drivers of ecosystem *** patterns on this relationship have been found,including positive,unimodal,negative,and neutral trends,keeping the issue *** this study,taxonomic diversity and functional diversity as drivers of above-ground biomass(AGB)were compared,and the mechanisms that influence biomass production were investigated by testing the complementarity and the mass-ratio ***:Using data from 414 permanent sample plots,covering 23%of temperate forest in the Sierra Madre Oriental(México),we estimated the above-gound biomass(AGB),taxonomic and functional diversity indices,as well as community weighted mean values(CWM)for three functional traits(maximum height,leaf size and wood density)for trees≥7.5 cm DBH,in managed and unmanaged *** compare taxonomic diversity differences between managed and unmanaged stands we carried out a rarefaction ***,we evaluated the relationship between AGB and taxonomic and functional diversity metrics,as well as CWM traits throught spatial autoregressive ***:We found a hump-shaped relationship between AGB and species richness in managed and unmanaged *** of maximum height was the most important predictor of AGB in both stands,which suggested that the mechanism underlaying the AGB-diversity relationship is the dominance of some highly productive species,supporting the mass-ratio ***-ground biomass was significantly correlated with three of the five functional diversity metrics,CWM maximum height and species *** results show the importance of taking into account spatial autocorrelation in the construction of predictive models to avoid spurious patterns in the AGBdiversity ***:Species richness,maximum height,functional richness,functional dispersion and Rao

关键词： Taxonomic diversity Functional diversity Complementarity hypothesis Mass-ratio hypothesis

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Venopulmonary ECMO Improved Hypoxemia and Supported the Right Ventricle in a Patient with Decompensated Eisenmenger Syndrome

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World Journal of Cardiovascular Surgery（心血管外科国际期刊） 2024年第1期

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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

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Prenatal Playful-Educational Activities, Psycho-Emotional Well-Being of Pregnant Women and Perinatal Outcomes: A Pilot Study

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Open Journal of Obstetrics and Gynecology 2021年第2期11卷 102-116页

作者： Jaime Salvador-Moysén Blanca Edith Cobián-lópez Yolanda Martínez-lópez edgar Felipe lares-Bayona María del Socorro Páez-Güereca Academic Group of Public Health and Epidemiology Institute of Scientific Research Universidad Juárez del Estado de Durango Durango México Academic Group of Public Health and Epidemiology Institute of Scientific Research Universidad Juárez del Estado de Durango Durango México Child Care and Development Center “Francisco Villa” Durango México

Objective: To present the results of a pilot study that evaluated the psycho-emotional well-being, and the perinatal results of a group of 44 women who attended a prenatal program that incorporates playful and educati... 详细信息

ng>Objective:ng> To present the results of a pilot study that evaluated the psycho-emotional well-being, and the perinatal results of a group of 44 women who attended a prenatal program that incorporates playful and educational activities, in a Child Development Center in Durango. Mexico. Methods: A group of 44 women with informed consent participated for 28 weeks in the prenatal program. The condition of psycho-emotional well-being during the first and third trimesters and the perinatal results were analyzed with validated instruments. Physiological stress was also assessed with salivary cortisol in the same trimesters. Results: More than 90% of the women evaluated their psycho-emotional condition as satisfactory and very satisfactory. The evaluation of anxiety in its Trait/State modalities placed the participants in the category of mild and moderate. Salivary cortisol showed values within a normal range. Perinatal results showed that 98% of deliveries were at term, 93% of newborns weighed more than 2500 grams, and 98% of newborns had an APGAR score of 9 at 5 minutes. Conclusion: The results suggest that the incorporation of playful and educational actions to prenatal surveillance positively influenced the biopsychosocial condition of the pregnant woman and favorable perinatal outcomes.n>

关键词： Prenatal Care Prenatal Education Playful Activities Maternal Health Healthy Pregnancy Comprehensive Health Care

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Pesticide-Handling Practices in Agriculture in El Salvador: An Example from 42 Patient Farmers with Chronic Kidney Disease in the Bajo lempa Region

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Occupational Diseases and Environmental Medicine 2014年第3期2卷 56-70页

作者： Roberto Mejía edgar Quinteros Alejandro lópez Alexandre Ribó Humberto Cedillos Carlos M. Orantes Eliette Valladares Dina l. lópez Department of Geological Sciences Ohio University Athens OH USA national Institute of Health Ministry of Health of El Salvador San Salvador El Salvador University of El Salvador San Salvador El Salvador

Introduction: The occupational toxic risks from agricultural activities in El Salvador affect human and environmental health. The objective of this paper is to describe the management of pesticide by farmers confirmed with a chronic kidney disease of uncertain etiology (CKDu) not associated to diabetes mellitus or hypertension. Methods: The study involved 42 male patients older than 18 years old with confirmed CKDu that have participated in different stages of pesticides management. This is a cross-sectional study;it was conducted from January to June 2011, in three communities of Bajo lempa region, El Salvador. An interview was especially designed to investigate which pesticides were used and the farmer practices at different stages of pesticide use. Statistical descriptive analysis was carried out for the several studied variables. Results: All interviewed people had a direct relationship with agricultural activities. The majority of patients had poor education, 19% were illiterate and 55% only have primary education. Most farmers with CKDu had been exposed more than 10 years to hazardous pesticides. The most used pesticide was Hedonal/2, 4 D (100%). 95% interviewed patients mixed different pesticides and 63% dumped empty pesticide containers in the fields. Interviewees did not use appropriate personal protective equipment (100%). Conclusions: There is high use of hazardous pesticides by patients and some of these are banned and some are legal in El Salvador, but prohibited by other countries. Interviewed CKDu patients had high exposure to toxic pesticides due to the misuse in almost all stages. There is inadequate legislation and a poor law enforcement to prevent the misuse of pesticides in El Salvador.

关键词： Bajo lempa Pesticides El Salvador CKDu Chronic Kidney Disease of Uncertain Etiology

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