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Analysis of heterogeneous characteristics in a geothermal area with low permeability and high temperature

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Geoscience Frontiers 2017年第5期8卷 1039-1050页

作者： Alfonso Aragón-Aguilar Georgina Izquierdo-montalvo Siomara López-Blanco Víctor Arellano-Gómez Instituto Nacional de Electricidad y Energías Limpias Reforma 113 Col.Palmira Cuernavaca Morelos CP 62490 Mexico

An analytical methodology for reservoir characterization was applied in the central and southwestern zones of Los humeros geothermal field(LhGF). This study involves analysis of temperature, pressure,enthalpy and permeability in wells and their distribution along the area. The wells located in the central western side of the geothermal field are productive, whereas those located at the central-eastern side are non-productive. Through temperature profiles, determined at steady state in the analyzed wells, it was observed that at bottom conditions(approximately 2300 m depth), temperatures vary between 280 and360℃. The temperatures are higher at the eastern side of central zone of LhGF. A review of transient pressure tests, laboratory measurements of core samples, and correlation of circulation losses during drilling suggest that permeability of the formation is low. The enthalpy behavior in productive wells shows a tendency of increase in the steam fraction. It was found that productivity behavior has inverse relation with permeability of rock formation. Further, it is observed that an imbalance exists between exploitation and recharge. It is concluded from the results that the wells located at central-eastern area have low permeability and high temperature, which indicates possibility of heat storage.

关键词： Los humeros geothermal field Reservoir performance hot rock Enthalpy Permeability Recharge

Isolation, Cultivation, and morphological Characteristics of hair Follicle Adult Stem Cells in the Bulge Region in mouse and human

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microscopy Research 2020年第2期8卷 9-30页

作者： Bélgica J. molina héctor J. Finol Center for Electron microscopy Science Faculty Central University of Venezuela Caracas Venezuela Dermatology Service University Hospital of Caracas Caracas Venezuela

Skin contains various populations of stem cells (SCs). Among these are hair follicle stem cells (hFSCs) in the bulge region. The behavior of hFSCs deserves to be widely studied due to the benefits to be derived from their identification, isolation, and amplification. Skin samples of newborn mice (n = 32) and human adults (n = 10) were used, and the bulge region was isolated and cultured. The isolation and characterization of cells were conducted through immunocytochemistry and immunofluorescence, using mainly CD34 and CD200 monoclonal antibodies. Initially, cells grew slowly from the explant around the bulge region, accruing cells with different morphology in both mouse and human, latter being mostly polygonal;the mouse cells reaching confluence faster (5 to 7 days) than the human (12 to 15 days). It was possible to isolate into subcultures cells with small size (10 - 13 μm diameter), round-shape, scant cytoplasm, central prominent nucleus and with nucleolus, which formed colonies, maintaining their phenotype in a high proportion (77% - 83% and 91% in mouse and human, respectively), without showing changes in their morphology during almost 7 months in the mouse cells, and a month and a half in the human. These results demonstrate that the selection, the isolation, and the conditioned mediums allowed population increases of bulge cells and indicate that cultured cells may retain their sternness in that they maintained their phenotypic characteristics, expressed specific markers for SCs, and showed a high proliferative capacity for long periods. hair follicles, in mice and humans, are important repositories of multipotent stem cells, due to their tendency to differentiate into keratinocytes. human hFSCs, obtained by depilation, preserve their potential for proliferation and prove to be easily accessible. This suggests that the bulge cells may present an alternative source of autologous stem cells for tissue engineering and regenerative medicine.

关键词： Stem Cells hair Follicle Bulge Niche Alopecia

meckel's diverticulum diagnosis by video capsule endoscopy: A case report and review of literature

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World Journal of Clinical Cases 2018年第14期6卷 791-799页

作者： Diego García-Compeán Alan R Jiménez-Rodríguez Angel N Del Cueto-Aguilera Gilberto herrera-Quinones José A González-González héctor J maldonado-Garza Gastroenterology Service and Department of Internal medicine Faculty of Medicine University Hospital "Dr. José E. González" Universidad Autónoma de Nuevo León Monterrey 64700 Nuevo León México

BACKGROUND meckel’s diverticulum （mD） occurs predominantly in chil-dren and adolescents. It is rarely diagnosed in adults. Preoperative diagnosis is diffcult due to low sensitivity of the radiological imaging studies. The role of video capsule endoscopy （VCE） in the diagnosis of mD is unknown, and the endoscopic patterns are not defned. We will describe four of our cases of mD evaluated with VCE and make a review of the literature focusing on the endoscopic *** SUmmARYWe present four cases of mD confirmed by surgery. They were all adult males with ages going from 18 to 50 years, referred to our service from 2004 to 2018, due to obscure gastrointestinal bleeding （OGIB）. TheyGarcía-Compeán D et al . merckel’s diverticulum diagnosis by VCEhad a history of 1 mo to 10 years of overt and occult bleeding episodes. Laboratory blood test showed an iron-deficiency anemia from 4 to 9 g/dL of hemoglo-bin that required multiple hospitalizations and blood transfusions in all cases. Repeated upper digestive endoscopies and colonoscopies were negative. Small bowel was examined with VCE, which revealed double lumen images in all cases, one with polyps and three with circumferential ulcers in the diverticulum. however, based on VCE findings, preoperative diagnosis of mD was suggested only in two patients. Capsule was retain-ed in one patient, which was recovered with surgery. The anatomopathological report revealed ulcerated ectopic gastric mucosa in all *** is useful for the diagnosis of mD. however, endo-scopic characteristics must be recognized in order to establish preoperative diagnosis.

关键词： meckel’s diverticulum Endoscopic features Video capsule endoscopy Wireless capsule endoscopy Review Case report

Comparing the biogeochemical functioning of two arid subtropical coastal lagoons:the effect of wastewater discharges

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Ecosystem health and Sustainability 2021年第1期7卷 49-60页

作者： Julio medina-Galván Carmen Cristina Osuna-martínez Gustavo Padilla-Arredondo martín Gabriel Frías-Espericueta Ramón héctor Barraza-Guardado JoséAlfredo Arreola-Lizárraga Facultad de Ciencias del mar Universidad Autónoma de SinaloaMazatlánMéxico Programa de Planeación Ambiental y Conservación Centro de Investigaciones Biológicas del NoroesteS.C.GuaymasMéxico Departamento de Investigaciones Científicas y Tecnológicas de la Universidad de Sonora HermosilloMéxico

Nutrient flux,net metabolism,and N2 fixation and denitrification processes were estimated and compared in two semi-arid subtropical coastal lagoons in the Gulf of California:El Soldado(ES),where no wastewater is discharged,and El Rancho(ER),where shrimp farm effluents are regularly *** processes were evaluated with the LOICZ *** time wash *** fluxes were higher in ER than in ES and both systems acted as nutrient sinks for most of the *** showed a larger nutrient flow rate in the summer and autumn due to the input of shrimp-farm *** fluxes increased in both ER and ES in the winter in response to the increased nutrient supply from coastal *** and ES both showed autotrophic metabolism and N2 fixation in the spring,autumn,and winter,but heterotrophic metabolism and denitrification in the *** dominated in ER(−2.21 mmol m^(2)day^(−1))and values were higher than those estimated in ES(−0.45 mmol m^(2)day^(−1)).The comparative analysis between ES and ER evidenced the significant changes in its biogeochemical performance caused by the input of anthropogenic nutrients,and can orient the environmental management of coastal lagoons.

关键词： Coastal lagoons nutrient budgets net ecosystem metabolism Gulf of California

Non-linear modeling of kinetic and equilibrium data for the adsorption of hexavalent chromium by carbon nanomaterials:Dimension and functionalization

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Chinese Journal of Chemical Engineering 2019年第4期27卷 912-919页

作者： miguel de la Luz-Asunción Eduardo E.Pérez-Ramírez Ana L.martínez-hernández Victor m.Castano Víctor Sánchez-mendieta Carlos Velasco-Santos Facultad de Quimica Universidad Autonoma del Estado de Mexico Km. 12 de la carretera Toluca-Atlacomulco C.P. 50200 San Cayetano Toluca Estado de Mexico Mexico Tecnologico Nacional de mexico-Instituto Tecnologico de Queretaro Division de Estudios de Posgrado e Investigacion Av. Tecnologico s/n esq. GraL Mariano Escobedo Col. Centro Historico C.P. 76000 Santiago de Queretaro Queretaro Mexico Centro de Fisica Aplicada y Tecnologia Avanzada Universidad Nacional Autonoma de Mexico Boulevard Juriquilla 3001 Queretaro 76230 Mexico

The adsorption capacities for the removal of hexavalent chromium from aqueous solutions by six carbon nanomaterials have been evaluated. Single-walled and multi-walled carbon nanotubes as received and after oxidation treatment, graphene oxide and reduced graphene oxide are the materials with different dimension and functionalization compared in this research. Carbon nanotubes have been modified using hydrogen peroxide as oxidizing agent under microwave radiation. The oxidation treatment on carbon nanotubes has a positive effect increasing the adsorbent–adsorbate interaction. Rate-controlling mechanisms and equilibrium data are analyzed using non-linear models. Non-linear method is proposed as the most suitable method for determining the kinetic and equilibrium parameters. The values of adsorption energy(E) obtained from the Dubinin–Radushkevich isotherm,have been found around 0.371 and 0.870 k J·mol-1, indicating physical adsorption. Therefore, the pseudo-second order model represents better the kinetic experimental data. The results show that the Langmuir isotherm provides a slightly better fit to the experimental data compared with the Freundlich isotherm, indicating homogeneous distribution of active sites on carbon nanomaterials and monolayer adsorption. The separation factors RLare found in the range of 0–1, suggesting that the adsorption process is suitable for all adsorbents. The mechanisms for hexavalent chromium removal have been proposed as electrostatic interactions and hydrogen bonding.

关键词： Carbon nanotubes Graphene Adsorption hexavalent chromium Kinetic

Pt(S)[n(100)×(110)]表面Cu欠电位沉积(英文)

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电化学 2012年第5期18卷 410-426页

作者： Rubén Gisbert Víctor Climent Enrique herrero Juan m.Feliu 阿利坎特大学电化学研究所西班牙阿利坎特E-03080

本文研究了Cu在Pt(100)台阶面和(110)单原子台阶的欠电位沉积.发现若不考虑阴离子吸附,初始阶段Cu在台阶面和台阶处的电沉积同时进行.在电沉积满单层的伏安曲线上,可以观察到若干峰.通过对峰电荷与台阶密度关系的分析,可认为这些峰分别... 详细信息

本文研究了Cu在Pt(100)台阶面和(110)单原子台阶的欠电位沉积.发现若不考虑阴离子吸附,初始阶段Cu在台阶面和台阶处的电沉积同时进行.在电沉积满单层的伏安曲线上,可以观察到若干峰.通过对峰电荷与台阶密度关系的分析,可认为这些峰分别对应于不同的沉积位点.较正电位的峰对应于Cu在台阶面上的电沉积,而在台阶处Cu的电沉积则因溶液中的阴离子而具有不同的伏安性质.此外,还发现Pt电极表面的Cu沉积电荷转移数接近2e,且沉积初始阶段阴离子覆盖度不变.

关键词： Pt单晶电极 Cu 欠电位沉积台阶修饰

Spectral Comparison of Real Spectra with Site Effects Included vs mOC-2008 Teorical Spectra for Guadalajara City, mexico

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Open Journal of Civil Engineering 2013年第3期3卷 194-201页

作者： héctor E. Rodríguez Lozoya Tonatiuh Domínguez Reyes Alfredo Reyes Salazar Edén Bojórquez mora héctor E. Rodríguez Leyva Facultad de Ingeniería Universidad Autónoma de Sinaloa México D.F. México Observatorio Vulcanológico Universidad de Colima México D.F. México

Guadalajara city is the capital of the mexican federal state of Jalisco. It is located close to the Pacific coast and is subjected to a large seismic risk. We present a seismic response study for some sites along the city. We calculated response spectra of shear-waves by using seismic records of actual earthquakes registered on rock and near the source as Green functions and propagated them trough a flat and horizontal layered media using a linear equivalent method to compare them with the response spectra calculated according to the Federal Commission of Electricity (CFE) seismic design buildings manual (mOC-2008, 2008) which is widely used as reference on construction projects in mexico. Our results show that mOC-2008 manual underestimates the spectral amplitudes and frequency band for the response spectra.

关键词： Response Spectra Guadalajara Seismic Records Green Function

Contrasting arthropod communities associated with dwarf mistletoes Arceuthobium globosum and A. vaginatum and their host Pinus hartwegii

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Journal of Forestry Research 2018年第5期29卷 1351-1364页

作者： León F.Chávez-Salcedo mónica E.Queijeiro-Bolanos Víctor López-Gómez Zenón Cano-Santana Blanca E.mejía-Recamier Aurea mojica-Guzmán Laboratorio de Interacciones y Procesos Ecologicos Departamento de Ecología y Recursos Naturales Facultad de Ciencias Universidad Nacional Autonoma de Moico Av.Universidad 3000 04510 Mexico City Mexico Laboratorio de Ecología y Sistemática de microartr dpodos Departamento de Ecología y Recursos Naturales Facultad de Ciencias Universidad Nacional Autónoma de M4xico Av.Universidad 3000 04510 Mexico City Mexico Instituto de Biologia Universidad Nacional Autdnoma de Mexico Av. Universidad 3000 04510 Mexico City Mexico Departamento de Ecologia Facultad de Ciencias Naturales Universidad Autdnoma de Quer6taro Av.de las Ciencias s/n 76230 Queretaro Queretaro Mexico

Arthropod communities and epiphytic plants associated with tree canopies have been widely studied and have revealed a great diversity of organisms; however,the community hosted by parasitic plants,such as dwarf mistletoes,remains poorly *** the coniferous forests of North America,dwarf mistletoe infection（Arceuthobium spp.） significantly damages the health of the forest,causing large financial losses for the forest industry,but it also positively affects diversity,especially of mammals and *** study examined the attributes of the arthropod communities associated with two species of dwarf mistletoe [Arceuthobium globosum hawksw.＆ Wiens and ***（humb.＆ *** Willd.） ***] and their host Pinus hartwegii *** 2010,in five sites located in Zoquiapan（Central mexico）,we collected plant tissue from the three species *** were separated from the plant tissue and identified to the finest level *** collected 32,059 individuals,for which51 morphospecies were identified,belonging to 15 taxonomic orders; the most abundant orders for the three plants were Prostigmata,Thysanoptera and *** community associated with *** had the highest value of diversity（h＇= 1.47; ***,h＇= 0.64; ***,h＇= 0.68） and species richness（S = 40; ***,S = 30; ***,S = 35）; while abundance was significantly higher for the mistletoes（***,n = 407 individuals/sample; ***,n = 536 individuals/sample; ***,n = 134 individuals/sample）.Species richness,abundance and diversity were significantly different for the three studied plants,as well for sampling month and the interaction of these two factors（except for diversity）.The results suggest that the canopy of *** is an important element in the ecosystem,providing a mosaic of resources and conditions to the associated *** also propose that mistletoes are key species within the forest canopy,as they greatly influence the establishment of d

关键词： Arceuthobium spp Pinus hartwegii Arthropod community Thrips mites hemiparasitic plants

Filter Efficiency with Red Rock as Post-Treatment of Stabilization Pond Effluent, Prototype Case Study San marcos, Carazo, from April to September 2019

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Open Journal of Applied Sciences 2022年第5期12卷 806-817页

作者： Víctor Rogelio Tirado Picado American University (UAm) Managua Nicaragua

An experimental unit was built which was located in the vicinity of the domestic wastewater treatment plant of the municipality of San marcos in the Department of Carazo. Said unit consisted of two welded metal barrels with a total height of 1.8 m and a diameter of 0.90 m, likewise, this unit comprised three functional zones;the first or input area composed of a collection unit, a driving unit, a flow control unit, and two distribution units;the second or packed zone, which is the axis of the system because it is there where bacterial growth takes place and where the removal of organic matter takes place;and an outlet composed of PVC pipe [1]. The main objective of this work was to determine how efficient a rocky filter turns out to be, using stabilization pond effluent as a post-treatment unit using red concrete as a filter medium. The study consisted in carrying out laboratory tests on water samples taken from the influent and effluent of a filter made up of red rock, as a filter medium, in order to determine the percentage of organic matter removal efficiency that it has used a hydraulic retention time of 19 hours, 15 hours, and 12 hours [2]. Among the aspects to be considered in the experimental study was the characterization of the effluent from the treatment system of San marco, Carazo, to determine the quality of water that will be of interest to the study [3]. In this stage, four composite samplings were carried out, two of 12 hours and two of 24 hours, in which physical, chemical, and microbiological parameters were analyzed. Likewise, to determine the efficiency of the filter, the same parameters considered in the characterization of the lagoon effluent were analyzed, obtaining removal efficiencies of up to 55.53% in organic matter, and 64.60% in suspended solids for a hydraulic retention time of 19 hours;In the same way, the efficiency of the filter was carried out for retention times of 15 hours and 12 hours, in which organic matter removals of 67.84% an

关键词： Design Filter Flow Flocs Transport Water Quality