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Journal of Materials Science and Chemical Eng.neering 2015年第1期3卷 45-51页

作者： J. C. Díaz-g.illén E. E. g.anda-gutiérrez g. vargas-gutiérrez M. R. Díaz-g.illén J. A. Ag.ilar-Martínez L. álvarez-Contreras Corporación Mexicana de Investig.ción en Materiales S.A. de C.V.-Cátedras-CONACyT Saltillo México Centro de Investig.ción y Estudios Avanzados del IPN Saltillo México g.yPQ Instituto de Investigaciones Eléctricas Cuernavaca México Universidad Autónoma de Nuevo León FIME-CIIIA Apodaca México Centro de Investig.ción en Materiales Avanzados S.C. Chihuahua México

In this work, plasma-nitrided AISI 316L stainless steel samples were performed by ion nitriding.process under pulsed direct current (DC) discharg. at different current densities (1 to 2.5 mA/ cm2). The effect of nitriding.current density on the size of crystalline coherently diffracting.domains (crystallite size) and strain g.ade was investig.ted using.X-ray diffraction (XRD) coupled with Williamson-Hall method. Additionally, hardness and wear resistance of the nitriding.layer were characterized using.a Vickers indenter and pin-on-disk technique respectively. Results showed a decrease in crystallite size from 99 nm for untreated samples to 1.4 nm for samples nitrided at 2.5 mA/cm2 promoted both: an increase in hardness from 226 HV25g.to 1245 HV25g. and a considerably decrease in volume loss by wear effect.

关键词： Plasma Nitriding Strain Crystallite Size Hardness Wear Stainless

‘Reimag.ning.an Environment’Exploring.the skateboarder’s experience

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空中英语教室(高级版.彭蒙惠英语) 2025年第1期 28-29,47,48页

作者： Charlie vargas 不详

To a skater,the board is an extension of the *** like a skateboard,an ag.ng.body can show life’s hard knocks.“Skateboarding.is truly rebellious and punk in its ethos,”said author Jose Vadi.“Nobody should care how old someone is just as much as someone shouldn't care about their...g.nder[or]economic *** of those thing. should be the determining.factor of your ability to enjoy yourself on a skateboard.”

关键词： ag.ng someone life

g.een synthesis of g.ycolic acid throug. the electrocatalytic reduction of oxalic acid over black TiO_(2): An experimental and theoretical study

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Journal of Energ. Chemistry 2025年第1期100卷 544-556页

作者： Hug. Olvera-vargas Oscar Andrés Jaramillo-Quintero Luis Darío Alarcón León Orlando Castro-Ocampo Christian A.Celaya Marina E.Rincón Jesús Muñiz Instituto de Energ.as Renovables Universidad Nacional Autónoma de México(IER-UNAM)Priv.Xochicalco s/nCol.CentroTemixcoMorelos.CP 62580Mexico Centro de Nanociencias y Nanotecnolog.a Universidad Nacional Autónoma de México(UNAM)Km 107Carretera Tijuana-EnsenadaEnsenadaB.C.C.P.22800Mexico

Herein,we present the electrocatalytic four-electron hydrog.nation of oxalic acid into g.ycolic acid using.black TiO_(2)as an *** acid is an abundant compound found in several sources of org.nic *** results showed a hig. selectivity of black TiO_(2)toward g.ycolic acid,with the formation of g.yoxylic acid being.the rate-limiting.step (g.yoxylic acid is the two-electron intermediate).The hig.est Faradaic efficiency (FE) of 69.6%±8.3% was achieved at 10.2 mA cm^(-2)in 4 h of electrolysis using.an H-type cell operated at room temperature,with 50.2%±3.8% of oxalic acid conversion (deg.adation kinetic constant k=0.0042±0.0001 min-1),58.8%±7.0%of reaction yield and 1.2±0.18 g.L-1of g.ycolic acid production.A theoretical model of black TiO_(2)coming.from anatase TiO_(2)was implemented by introducing.Ti3+defects,which g.ve black TiO_(2)the theoretical capability to easily transform oxalic acid into g.ycolic acid as experimentally *** reaction mechanism was supported and described in detail by density functional theory calculations,which revealed that surface Ti^(3+)states were the main catalytic *** is the first time that a detailed step-by-step mechanism at the atomic level has been proposed for this electrocatalytic reaction,which represents a valuable contribution to the understanding.of this process of hig. energ./environmental *** is also the first time that black TiO_(2)has been used as an electrocatalyst for this sustainable process.

关键词： Chemical energ. storag. Electrochemical hydrog.nation Density functional theory Renewable energ. Oxalic acid

Surface Properties of Fe_4N Compounds Layer on AISI 4340 Steel Modified by Pulsed Plasma Nitriding

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Journal of Materials Science & Technolog. 2013年第3期29卷 287-290页

作者： J.C.Díaz-g.illén g.vargas-gutiérrez E.E.g.anda-gutiérrez J.S.Zamarripa-Pia S.I.Pérez-Ag.ilar J.Candelas-Ramírez L.lvarez-Contreras Centro de Investig.cin en Materiales Avanzados S.C.Miguel de Cervantes 120Complejo Industrial ChihuahuaC.P.31109 ChihuahuaChihuahuaMexico Corporacin Mexicana de Investig.cin en Materiales S.A.de C.V.Ciencia y Tecnología No 790Fracc.Saltillo 400C.P.25290 SaltilloCoahuilaMexico Centro de Investig.cin y Estudios Avanzados del IPN Unidad SaltilloCarretera Saltillo Monterrey km 13Apdo.Postal 663C.P.25000 SaltilloCoahuilaMexico

In this work, the effect of nitriding.current density on hardness, crystalline phase composition, layer thickness and corrosion rate of AlSl 4340 steel has been studied. X-ray diffraction analysis shows that thin layers formed during.nitriding.process are constituted of 7-Fe4N for samples processed between 1 and 2.5 mA/cm2. Thickness of nitrided layer increases proportionally to current density （0 μm for 0.5 mA/cm2 to 15 pm for 2.5 mA/cm2）. Plasma nitriding.increased the surface hardness from 300 HV50g.for untreated sample, to around 800HV5og.for nitrided samples at 1 mA/cm2. While the untreated samples exhibited a corrosion rate of 0.153 mm per year, the corrosion performance was improved up to 0.03 mm per year at current densities above 1 mA/cm2, which is about one fifth of the corrosion rate of the untreated sample.

关键词： Plasma nitriding Current density Hardness Corrosion

Thinking.outside the black box:are the brain endothelial cells the new main targ.t in Alzheimer's disease?

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Neural Reg.neration Research 2023年第12期18卷 2592-2598页

作者： Enrique Estudillo Adolfo López-Ornelas Alejandro Rodríg.ez-Oviedo Neptali gutiérrez de la Cruz Marco Antonio vargas-Hernández Adriana Jiménez Laboratorio de Reprog.amación Celular Instituto Nacional de Neurología y Neurocirugía Manuel Velasco SuárezMexico CityMexico División de Investig.ción Hospital Juárez de MéxicoMexico CityMexico Hospital Nacional Homeopático Hospitales Federales de ReferenciaMexico CityMexico Facultad de Ciencias Universidad Nacional Autónoma de MéxicoMexico CityMexico Laboratorio de Morfolog.a Escuela Militar de Graduados de SanidadSecretaría de la Defensa NacionalBatalla de CelayaLomas de SoteloMiguel HidalgoMexico CityMexico Escuela Militar de g.aduados de Sanidad Secretaría de la Defensa NacionalBatalla de CelayaLomas de SoteloMiguel HidalgoMexico CityMexico

The blood-brain barrier is the interface throug. which the brain interacts with the milieu and consists mainly of a sophisticated network of brain endothelial cells that forms blood vessels and selectively moves molecules inside and outside the brain throug. multiple mechanisms of *** brain endothelial cell function is crucial for brain homeostasis,their role in neurodeg.nerative diseases has historically not been considered with the same importance as other brain cells such as microg.ia,astrog.ia,neurons,or even molecules such as amyloid beta,Tau,or ***'s disease is the most common neurodeg.nerative disease,and brain endothelial cell dysfunction has been reported by several ***,its impairment has barely been considered as a potential therapeutic *** we review the most recent advances in the relationship between Alzheimer's disease and brain endothelial cells commitment and analyze the possible mechanisms throug. which their alterations contribute to this neurodeg.nerative disease,hig.lig.ting.their inflammatory phenotype and the possibility of an impaired secretory pattern of brain endothelial cells that could contribute to the prog.ession of this ***,we discuss why shall brain endothelial cells be appreciated as a therapeutic targ.t instead of solely an obstacle for delivering.treatments to the injured brain in Alzheimer's disease.

关键词： dementia endothelial cells neurodeg.neration neuroinflammation neuronal death paracellular transport transcellular transport

Tick-Borne Rickettsial Pathog.ns in Rodents from Mexico

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Journal of Biomedical Science and Eng.neering 2014年第11期7卷 884-889页

作者： Carolina g. Sosa-gutiérrez Marg.rita vargas Javier Torres g.adalupe g.rdillo-Pérez Facultad de Ag.obiolog.a Universidad Michoacana de San Nicolas de Hidalgo Uruapan México Unidad de Investig.ción Médica de Enfermedades Infecciosas y Parasitarias Hospital de Pediatría Centro Médico Nacional Siglo XXI Instituto Mexicano del Seguro Social Mexico City Mexico

Tick-Borne Rickettsial Diseases (TBRD) are emerg.ng.zoonotic diseases, and a problem of human health and veterinary medication. The distribution of these diseases is related to the distribution of vector. The presence of pathog.ns in the host is a risk indicator of population exposure to these areas. A total of 478 tissues samples from rodents, A. phag.cytophilum 18 (3.7%), E. canis 47 (9.8%), Rickettsia rickettsii 18 (3.7%) and E. chaffeensis 19 (3.9%) were detected using.species-specific PCR assay. It is the first report in Mexico the presence of rodents infected with A. phag.cytophilum and E. chaffeensis. The rodent Peromyscus spp. were the most commonly prevalent host of infection for all the bacteria’s. We have to consider as host of TBRD transmitter and provide a useful contribution to understanding.their epidemiolog.. The health sector should be considered all the fevers of unknown causes in humans and animals in Mexico as infections by these vector-borne rickettsial pathog.ns.

关键词： Anaplasma phag.cytophilum Ehrlichia chaffeensis Rickettsia rickettsii Ehrlichia canis Rodents

Vig.rous,but differential mononuclear cell response of cirrhotic patients to bacterial lig.nds

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World Journal of g.stroenterolog. 2011年第10期17卷 1317-1325页

作者： Varenka J Barbero-Becerra María Concepción gutiérrez-Ruiz Carmen Maldonado-Bernal Félix I Téllez-Avila Roberto Alfaro-Lara Florencia vargas-Vorácková Department of g.stroenterolog. Instituto Nacional de Ciencias Médicasy Nutrición Salvador Zubirán Laboratorio de Fisiolog.a Celular División de Ciencias de la Salud Universidad Autónoma Metropolitana-Iztapalapa Unidad de Investig.ción Médica en Enfermedades Infecciosasy Parasitarias Hospital de Pediatría Unidad de Investig.ción en Enfermedades Oncológ.cas Hospital Infantil de México Federico Gómez

AIM： To study the role of g.am-positive and g.am-neg.tive bacteria in the pathog.nesis of liver injury, specifically the activation of inflammatory mediators. METHODS： Peripheral blood mononuclear cells of 20 out-patients were studied, 10 of them with cirrhosis,Peripheral blood mononuclear cells were isolated and exposed to lipopolysaccharide or lipoteichoic acid. CD14, Toll-like receptor 2 and 4 expression was determined by flow cytometry, and tumor necrosis factor （TNF） α, interleukin （1L）-1β, IL-6, IL-12 and IL-10 secretion in su- pernatants was determined by ELISA. RESULTS： Hig.er CD14, Toll-like receptor 2 and 4 expression was observed in peripheral blood mononudear cells from cirrhotic patients, （P 〈 0.01, P 〈 0.006, P 〈 0.111） respectively. Lipopolysaccharide and lipoteichoic acid induced a further increase in CD14 expression （P 〈 0.111 lipopolysaccharide, P 〈 0.013 lipoteichoic acid）, and a decrease in Toll-like receptor 2 （P 〈 0.008 lipopolysaccharide, P 〈 0.008 lipoteichoic acid） and Toll-like receptor 4 （P 〈 0.008 lipopolysaccharide, P 〈 0.028 li- poteichoic acid） expression. With the exception of TNFα, absolute cytokine secretion of peripheral blood mononuclear cells was lower in cirrhotic patients under nonexposure conditions （P 〈 0.070 IL-6, P 〈 0.009 IL-1]5, P 〈 0.022 IL-12）. Once exposed to lipopolysaccharide or lipoteichoic acid, absolute cytokine secretion of peripheral blood mononuclear cells was similar in cirrhotic and non-cirrhotic patients, determining.a more vig.rous response in the former （P 〈 0.005 TNFα, IL-1β, IL-6, IL-2 and IL-10 lipopolysaccharide; P 〈 0.037 TNFα; P 〈 0.006 IL-113; P 〈 0.005 IL-6; P 〈 0.007 IL-12; P 〈 0.014 IL-10 lipoteichoic acid）. Response of peripheral blood mononuclear cells was more intense after lipopolysaccharide than after lipoteichoic acid exposure. CONCLUSION： Peripheral blood mononuclear cells of cirrhotic patients are able to respond to a sudden bacterial lig.nd exposure, particularly lipopolysaccharide, sug.

关键词： Liver cirrhosis Toll-like receptors Cytokines Lipopolysaccharide Lipoteichoic acid

Selection and Analysis of Polymorphisms in Somaclonal Variants of Ag.ve americana Resistant to Fusarium oxysporum via an Ethyl Methanesulphonate Treatment

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Phyton-International Journal of Experimental Botany 2021年第6期90卷 1727-1739页

作者： Sheila Jazmín Reyes-Zambrano Carlos Alberto Lecona-g.zmán Federico Antonio gutiérrez-Miceli Víctor Manuel Ruiz-Valdiviezo Arely Anayansi vargas-Díaz Laboratorio de Biotecnolog.a Veg.tal Instituto Tecnológico de Tuxtla GutiérrezTecnológico Nacional de MéxicoTuxtla GutiérrezChiapas29050México CONACYT-Coleg.o de Postg.aduados Campus Campeche ChampotónCampeche24450México

Ag.ve americana *** were exposed to different concentrations of ethyl methanesulphonate(EMS)0,15,30,45 and 60 mM and to different times of exposure(2 and 4 h).The viability and capacity of shoot formation were shown to be affected when the callus were exposed to hig. concentrations(30–60 mM).Only the callus exposed to 15 mM EMS presented shoot formation;the exposure time of two hours produced the larg.st quantity of shoots reg.nerated per callus(21 shoots/callus).In order to g.nerate somaclonal variants resistant to Fusarium oxysporum,a selection pressure was applied throug. of a culture filtrate(CF)of 100 ppm of the *** was made in callus obtained in the treatment with 15 mM EMS during.2 h of *** CF caused oxidation and necrosis in 71.25%of the callus;however,they were capable of g.nerating.shoots(3.5 shoots/callus).Molecular markers type RAPD,ISSR and DAMD were used to evaluate the g.netic variation arising.from the mutations caused by EMS on control plants and 16-month-old somaclonal *** polymorphic information content(PIC)for each one of the initiating.g.oups was:0.28(DAMD),0.09(ISSR)and 0.14(RAPD).DAMD revealed a g.eater percentag. of polymorphism than RAPD and *** bands were detected in the somaclonal *** indicated that the EMS caused g.netic variation in the reg.nerated plants conferring.resistance to them ag.inst Fusarium oxysporum.

关键词： Mutag.nesis polymorphisms g.netic variation molecular markers

Potential Species Distribution and Richness of Ixodidae Ticks Associated with Wild Vertebrates from Michoacán, Mexico

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Journal of g.og.aphic Information System 2014年第5期6卷 467-477页

作者： Marg.rita vargas-Sandoval Ang.l g. Prieg.-Santander Alejandra Larrazábal Carolina g. Sosa-gutiérrez Blanca Lara-Chávez Teresita Avila-Val Facultad de Ag.obiolog.a “Presidente Juárez” Universidad Michoacana de San Nicolás de Hidalgo Uruapan México Centro de Investig.ciones en g.og.afía Ambiental UNAM Antigua Carretera a Pátzcuaro No. 8701 ExHacienda de San José de la Huerta Morelia México Unidad de Investig.ción Médica de Enfermedades Infecciosas y Parasitarias Hospital de Pediatría Centro Médico Nacional Siglo XXI México DF México

Ticks are reg.rded as the most relevant vectors of disease-causing.pathog.ns in domestic and wild animals. The diversity of Ixodidae is known for a very small number of ***?are represented by 26 species, and?in?2007 the first reported ticks vectors in Mexico for the causal ag.nt of Lyme disease. Recent rise in tick-borne disease in many parts of the world is a phenomenon in need of an explanation. The main objective of the present work was to map at a reg.onal scale (1:2,000,000)?of?the distribution of ticks of the family Ixodidae that are potentially present on the wild fauna of state of Michoacan, Mexico. We compiled all available literature on ticks at a national level tog.ther with complete cartog.aphic and bibliog.aphic g.oreferenced information of the distribution of hosts in order to build a spatial database in ArcView 3.3. The results indicated that the wild fauna in the state’s territory could potentially include 31 species of ticks of Ixodidae. The map of potential species richness of ixodid ticks on the wild fauna of the state can be categ.rized into five classes of species richness. The hig.est potential concentration of ixodid species on wild fauna occurs in the volcanic area of Pico de Tancítaro.

关键词： Ticks Ixodidae Michoacán g.og.aphic Distribution Potential Species Richness

秘鲁中部曼塔罗盆地土壤地球化学特征及质量评价

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地学前缘 2025年第1期32卷 219-235页

作者：刘君安朱意萍姜瀚涛 César De La Cruz POMA Oliberth Pascual g.DOY Luis Enrique vargas RODRíg.EZ 郭维民姚春彦王天刚张明姚仲友中国地质调查局南京地质调查中心江苏南京210016 秘鲁地质矿产冶金研究院(INg.MMET) 秘鲁利马15074

为加强中国与秘鲁两国地学合作,推广我国优势的地球化学调查与研究方法,中国地质调查局与秘鲁地质矿产冶金研究院(INg.MMET)以秘鲁中部曼塔罗(Mantaro)盆地为研究区共同开展了多目标地球化学调查,以我国现行相关行业规范为标准,采集样... 详细信息

为加强中国与秘鲁两国地学合作,推广我国优势的地球化学调查与研究方法,中国地质调查局与秘鲁地质矿产冶金研究院(INg.MMET)以秘鲁中部曼塔罗(Mantaro)盆地为研究区共同开展了多目标地球化学调查,以我国现行相关行业规范为标准,采集样品并于我国实验室进行分析测试。调查和研究表明:研究区土壤总体呈弱碱性,Au元素强烈富集,I、C、C_(org.、Cd和N等指标较富集;土壤养分指标N和P较丰富,K则较缺乏,土壤养分综合等级以较丰富(二等)为主,面积占比为74.1%,土壤肥力较好;土壤环境评价指标中,Zn和Pb在少量地区存在轻微—重度污染,Cd和As则有较大面积的污染,土壤环境综合等级以轻微污染和轻度污染为主,污染地区主要分布于曼塔罗河两侧5 km范围内,重度污染区则主要分布于紧邻曼塔罗河地区和人口密度最大的万卡约市周边,重金属污染较严重,污染空间分布与曼塔罗河密切相关;土壤质量综合评价等级主要为中等—劣等,面积占比达83.18%,优质和良好级土壤面积仅占16.82%。综上所述,秘鲁曼塔罗盆地地区土壤养分较丰富,土壤重金属污染较严重,土壤综合质量为中等偏差,建议秘鲁有关部门加强对曼塔罗河及上游重金属污染源的环境管理与整治。

关键词：曼塔罗盆地多目标地球化学调查土地质量地球化学特征秘鲁