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Synthesis and characterization of nano-hydroxyapatite added with magnesium obtained by wet chemical precipitation

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Progress in natural Science:Materials International 2021年第4期31卷 575-582页

作者： Brandon A.Correa-Pi?a Omar M.Gomez-Vazquez Sandra M.Londo?o-Restrepo Luis F.Zubieta-Otero Beatriz M.Millan-Malo Mario E.Rodriguez-García Posgrado en ciencia e Ingeniería de Materiales Centro de Física Aplicada y Tecnología Avanzada Universidad Nacional Autónoma de México Campus Juriquilla departamento de nanotecnología Centro de Física Aplicada y Tecnología Avanzada Universidad Nacional Autónoma de México Campus Juriquilla

Biogenic hydroxyapatites from mammalian bones naturally contain traces of ions, like Mg, which play a vital role in the bone remodeling process. In this way, synthetic hydroxyapatites should include this kind of mineral. In this work, hydroxyapatite added with Mg was synthesized by wet precipitation using（nH;）H;PO;, Ca（nO;）;.4 H;O,and Mg（nO;）;.6 H;O（0, 0.032, 0.061, and 0.123 M）. Inductively coupled plasma and X-ray diffraction evidenced the Mg inclusion in the hydroxyapatite lattice in the same levels reported for natural hydroxyapatites. The calcination at 600℃ was performed to remove the reaction by-products, but it also gave rise to physicochemical changes as the coalescence and crystals recrystallization. It produced, in turn, an improvement in the crystalline quality, according to Raman analysis. despite those physicochemical changes, all the samples remained nanometric according to scanning electron microscopy imaging.

关键词： Magnesium Physicochemical properties Calcination nanometric crystal size Coalescence Recrystallization

Synthesis and Thermal Behavior of Metallic Cobalt Micro and nanostructures

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nano-Micro Letters 2011年第1期3卷 12-19页

作者： Marlene González Montiel P.Santiago-Jacinto J.A.I.Díaz Góngora E.Reguera Geonel Rodríguez-Gattorno Centro de Investigación en Ciencia Aplicada y Tecnología Avanzada Instituto de Física Circuito de la Investigación Científica Ciudad Universitaria departamento de Física aplicada CINVESTAV-IPN

In this contribution, a comparative study of metallic cobalt micro and nanoparticles obtained in solution by four different chemical routes is reported. Classic routes such as borohydride reduction in aqueous media and the so-called polyol methodology were used to obtain the cobalt nanostructures to be studied. Using CTAB as surfactant, cobalt hollow nanostructures were obtained. The use of strong reducing agents, like sodium borohydride, favors the formation of quasi-monodispersed nanoparticles of about 2 nm size but accompanied with impurities; for hydrazine(a mild reducer), nanoparticles of larger size are obtained which organize in spherical microagglomerates. Valuable information on the particles thermal stability and on nature of the species anchored at their surface was obtained from thermogravimetric curves. The samples to be studied were characterized from UV-vis, IR, X-ray diffraction, and electron microscopy images(scanning and transmission).

关键词： Metallic Cobalt Cobalt nanoparticles Magnetic nanoparticles Hollow magnetic microparticles

Hydrodeoxygenation of vegetable oil in batch reactor:Experimental considerations

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Chinese Journal of Chemical engineering 2020年第6期28卷 1670-1683页

作者： Alexis K.noriega Alexis Tirado Cecilia Méndez Gustavo Marroquín Jorge Ancheyta Instituto Politécnico nacional Centro de Investigación en Ciencia Aplicada y Tecnología Avanzada Unidad LegariaLegaria 694Col.Irrigación 11500Mexico Instituto Mexicano del Petróleo Eje Central Lázaro Cárdenas Norte 152San Bartolo Atepehuacan 07730Mexico

The generation of reliable experimental data in any experimental scale requires proper procedures not only for the reaction step but also for the feed preparation,separation,and characterization of products as well as calculations of conversion and product yields.Batch reactor is the most used experimental setup for carrying out exploratory studies for catalyst screening and development.This work is focused on describing and discussing a step-by-step methodology for conducting experiments for catalytic hydrotreating of vegetable oils in batch reactor.The proposed methodology considers literature and own experiences on advantages and disadvantages of different feed types,catalysts,experimental setup and procedures,effect of reaction parameters,separation and characterization of products,and calculations.

关键词： Vegetable oils Hydrotreating Batch reactor

Presenilin mutations and their impact on neuronal differentiation in Alzheimer’s disease

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neural Regeneration Research 2022年第1期17卷 31-37页

作者： Mercedes A.Hernández-Sapiéns Edwin E.Reza-Zaldívar Ana L.Márquez-Aguirre Ulises Gómez-Pinedo Jorge Matias-Guiu Ricardo R.Cevallos Juan C.Mateos-Díaz Víctor J.Sánchez-González Alejandro A.Canales-Aguirre Unidad de Evaluación Preclínica Unidad de Biotecnología Médica y FarmacéuticaCentro de Investigación y Asistencia en Tecnología y Diseño del Estado de JaliscoGuadalajaraMéxico Instituto de neurociencias IdISSCHospital Clínico San CarlosMadridEspaña Biochemistry and Molecular Genetics department University of AlabamaBirminghamAlabama Unidad de Biotecnología Industrial Centro de Investigación y Asistencia en Tecnología y Diseño del Estado de JaliscoGuadalajaraMéxico centro Universitario de los Altos Universidad de GuadalajaraGuadalajaraMéxico

The presenilin genes(PSen1 and PSen2)are mainly responsible for causing early-onset familial Alzheimer’s disease,harboring~300 causative mutations,and representing~90%of all mutations associated with a very aggressive disease form.Presenilin 1 is the catalytic core of theγ-secretase complex that conducts the intramembranous proteolytic excision of multiple transmembrane proteins like the amyloid precursor protein,notch-1,n-and E-cadherin,LRP,Syndecan,delta,Jagged,CD44,ErbB4,and nectin1a.Presenilin 1 plays an essential role in neural progenitor maintenance,neurogenesis,neurite outgrowth,synaptic function,neuronal function,myelination,and plasticity.Therefore,an imbalance caused by mutations in presenilin 1/γ-secretase might cause aberrant signaling,synaptic dysfunction,memory impairment,and increased Aβ42/Aβ40 ratio,contributing to neurodegeneration during the initial stages of Alzheimer’s disease pathogenesis.This review focuses on the neuronal differentiation dysregulation mediated by PSen1 mutations in Alzheimer’s disease.Furthermore,we emphasize the importance of Alzheimer’s disease-induced pluripotent stem cells models in analyzing PSen1 mutations implication over the early stages of the Alzheimer’s disease pathogenesis throughout neuronal differentiation impairment.

关键词： familial Alzheimer’s disease familial Alzheimer’s disease-induced pluripotent stem cells models induced pluripotent stem cells neurogenesis neuronal differentiation notch presenilin 1 PSen1 mutations γ-secretase complex

A novel and stretchable carbon-nanotube/ni@TiO_(2):W photocatalytic composite for the complete removal of diclofenac drug from the drinking water

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Journal of environmental Sciences 2023年第4期126卷 575-589页

作者： Ernesto Valadez-Renteria Rafael Perez-Gonzalez Christian Gomez-Solis Luis Armando Diaz-Torres Armando encinas Jorge Oliva Vicente Rodriguez-Gonzalez Consejo nacional de ciencia y tecnología-División de Materiales Avanzados Instituto Potosino de Investigación Científica y TecnológicaSan Luis Potosí78216México División de ciencias e Ingenierías Universidad de GuanajuatoLeón 37150México Grupo de Espectroscopia de Materiales Avanzados y nanoestructurados(GEMAnA) Centro de Investigaciones enópticaA.C.Lomas Del CampestreLeón 37150México

We present the structural,morphological and photocatalytic properties of stretchable composites made with carbon nanotubes (CnTs),silicon rubber and ni@TiO_(2):W nanoparticles(TiWni nPs) with average size of 37±2 nm.Microscopy images showed that the TiWni nPs decorated the surface of the CnT fibers,which are oriented in a preferential direction.TiWni nPs presented a mixture of anatase/rutile phases with cubic structure.The performance of the TiWni powders and stretchable composites was evaluated for the photocatalytic degradation of diclofenac (DCF) anti-inflammatory drug under ultraviolet-visible light.The results revealed that the maximum DCF degradation percentages were 34.6%,91.9%,97.1%,98.5%and 100%for the CnT composite (stretched at 0%),TiWni powders,CnT+TiWni(stretched at 0%),CnT+TiWni (stretched at 50%) and CnT+TiWni (stretched at 100%),respectively.Thus,stretching the CnT+TiWni composites was a good strategy to enhance the DCF degradation percentage from 97.1%to 100%,since stretching created additional defects (oxygen vacancies) that acted as electron sink,delaying the electron-hole recombination,and favors the DCF degradation.Raman/absorbance measurements confirmed the presence of such defects.Moreover,the reactive oxygen species (ROS) were determined by the scavenger’s experiments and found that the main ROS were the·OH and O_(2)-radicals,which attacked the DCF molecules,causing their degradation.The results of this investigation confirmed that the stretchable CnT/TiWni-based composites are a viable alternative to remove pharmaceutical contaminants from water and can be manually separated from the decontaminated water,which is unviable using photocatalytic powders.

关键词： Diclofenac Pharmaceutical contaminant TiO_(2) Carbon nanotubes Stretchable composite Photocatalysis

Identification of Cu in <i>Crassostrea virginica</i>Tissue Using the Technique of Laser-Induced Breakdown Spectroscopy (LIBS)

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Optics and Photonics Journal 2021年第3期11卷 51-62页

作者： Xochitl Patricia Urrutia-Meza Fabio Felipe Chalé-Lara Rogelio Ortega-Izaguirre Instituto Politécnico nacional Centro de Investigación en Ciencia Aplicada y Tecnología Avanzada U. Altamira Altamira México

The analysis of metals in aquatic organisms is of great importance due to the health problems they can cause to be consumed by human beings. In this study, the Laser-Induced Plasma Spectroscopy (LIBS) technique is evaluated as an alternative method to identify Cu in n>Crassostrea virginica oystersn>’n> tissue. It focuses on the characterization of oysters caught a natural bank and the identification of different Cu concentrations. To carry out experimentation, oyster samples were collected in autumn (October 2017) and spring (May 2018) from San Andres Lagoon, Aldama, Tamaulipas. A single pulse nd:yAG laser (1064 nm) was used, and tissue was contaminated with 0, 2, 10, 20, 50, and 100 μg/g of Cu. In tissue were identified atomic lines for Ca, Cr, Mg, Mn, na, n, O, and H. However, the intensities of emission lines for autumn samples were greater than spring samples. Cu emission lines at 324.6, 327.1, 510.3, 515.1, and 521.5 nm were found for contaminated pills. The intensity of emission lines showed a linear increase with the concentration;whereby, they can be used as calibration curves to quantify Cu concentrations in oyster tissue.

关键词： LIBS Crassostrea virginica Heavy Metals

DnA metabarcoding reveals seasonal changes in diet composition across four arthropod-eating lizard species(Phrynosomatidae:Sceloporus)

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Integrative Zoology 2024年第3期19卷 480-495页

作者： Mauricio HERnÁndeZ Stephanie HEREIRA-PACHECO Antton ALBERDI Aníbal H.DÍAZ de LA VEGA-PÉREZ Arturo ESTRADA-TORRES Sergio AnCOnA yendi E.nAVARRO-nOyA Doctorado en ciencias Biológicas Centro Tlaxcala de Biología de la ConductaUniversidad Autónoma de TlaxcalaTlaxcalaMexico Estación Científica La Malinche Centro Tlaxcala de Biología de la ConductaUniversidad Autónoma de TlaxcalaTlaxcalaMexico Center for Evolutionary Hologenomics The Globe InstituteUniversity of CopenhagenCopenhagenDenmark Consejo nacional de ciencia y tecnología-centro Tlaxcala de Biología de la Conducta Universidad Autónoma de TlaxcalaTlaxcalaMexico departamento de Ecología Evolutiva Instituto de EcologíaUniversidad Nacional Autónoma de MéxicoMexico CityMexico Laboratorio de Interacciones Bióticas Centro de Investigación en Ciencias BiológicasUniversidad Autónoma de TlaxcalaSan Felipe IxtacuixtlaTlaxcalaMexico

Diet composition and its ecological drivers are rarely investigated in coexisting closely related species.We used a molecular approach to characterize the seasonal variation in diet composition in four spiny lizard species inhabiting a mountainous ecosystem.DnA metabarcoding revealed that the lizards Sceloporus aeneus,S.bicanthalis,S.grammicus,and S.spinosus mostly consumed arthropods of the orders Hemiptera,Araneae,Hymenoptera,and Coleoptera.The terrestrial lizards S.aeneus and S.bicanthalis mostly predated ants and spiders,whereas the arboreal–saxicolous S.grammicus and saxicolous S.spinosus largely consumed grasshoppers and leafhoppers.The taxonomic and phylogenetic diversity of the prey was higher during the dry season than the rainy season,likely because reduced prey availability in the dry season forced lizards to diversify their diets to meet their nutritional demands.Dietary and phylogenetic composition varied seasonally depending on the species,but only dietary composition varied with altitude.Seasonal dietary turnover was greater in S.spinosus than in S.bicanthalis,suggesting site-specific seasonal variability in prey availability;no other differences among species were observed.S.bicanthalis,which lives at the highest altitude in our study site,displayed interseasonal variation in diet breadth.Dietary differences were correlated with the species’feeding strategies and elevational distribution,which likely contributed to the coexistence of these lizard species in the studied geographic area and beyond.

关键词： arthropod-eating lizards diet breadth environmental barcoding mountainous ecosystem seasonal dietary shifts

Variability in mentum deformities of Tanytarsus larvae(Diptera,Chironomidae)in a metal rich basin in northern Mexico

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Water Biology and Security 2022年第2期1卷 1-9页

作者： Orestes Carlos Bello-Gonzalez Perla Alonso-EguíaLis Cesar Arturo Ilizaliturri Hernandez norman Mercado-Silva centro de investigacion en Biodiversidad y Conservacion Universidad Autonoma del Estado de MorelosCuernavacaMorelosMexico Instituto Mexicano de tecnología del Agua JiutepecMorelosMexico Facultad de Medicina-centro de investigacion aplicada en Ambiente y Salud Universidad Autonoma de San Luis PotosíCoordinacion para la Aplicacion de la Ciencia y la Tecnología-(CIACyT-CIAAS)San Luis PotosíMexico

Mentum deformities in chironomids have been commonly used as indicators of metal contamination in freshwater ecosystems.Incidence of these deformities suggests sublethal effects and can provide early signals of environmental deterioration.While anthropogenic metal pollution is known to lead to an increase in deformities in chironomids,natural background deformity incidence information is key to their effective use as biomonitoring tools.Here we explore the incidence of deformities from 5000 Tanytarsus(Diptera,Chironomidae)menta in relation to water physicochemical,and sediment metal(Al,As,Cu,Fe,Mn,Pb,Zn)concentration data from numerous sites in the naturally metal-rich Sonora River(nW Mexico)obtained over a two-year period.Higher metal concentrations were found in the upper basin.Higher salinity,total suspended solids and conductivity were found in the lower basin.Only As and Cu were occasionally found above published threshold effect levels(TEL).The proportion of deformities(%D)was low(2.1%)and a generalized linear model only explained 25.36%of%D variability among samples;this model included several physicochemical parameters.The only metal significantly related to deformities was Cu.despite significant spatial and temporal variability in all metal concentrations and other physicochemical parameters in the basin,we were unable to explain a strong relationship between metal concentration and deformity incidence.Our results,based on consistent%D quantification from 5000 samples from a single taxon,suggest that natural variation in metal concentrations,even when statistically significant,is not associated with notable variations in the incidence of deformities.

关键词： Macroinvertebrate Pollution Sonora river desert river Copper Arsenic

Effects of Silicon nanoparticles on the Transient Liquid Phase Bonding of 304 Stainless Steel

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Journal of Materials Science & Technology 2014年第3期30卷 259-262页

作者： H.M.Hdz-García A.I.Martinez R.Mu?oz-Arroyo J.L.Acevedo-Dávila F.García-Vázquez F.A.Reyes-Valdes Corporación Mexicana de investigación en Materiales S.A.de C.V. Ciencia y Tecnología No.790 Fracc.Saltillo 400 Saltillo Coah.CP.25290 Mexico centro de investigación y de Estudios Avanzados del IPn Carr.Mty-Saltillo km.13 Ramos Arizpe Coah.CP.25900 Mexico

Transient liquid phase （TLP） bonding of 304 stainless steel with nickel based filler metal, Bni-9, was performed to study the influence of silicon nanoparticles （nPs） on the mechanical and structural properties of the bonding area. It was found that silicon nPs act as a melting point depressant in the brazing process; the formation of silicon TLP induces the dissolution of elements of the metal filler and promotes a uniform distribution in the bonding area. Silicon nPs induce the development of smaller eutectic structures in the melting zone; it has been related to microhardness measurements, which are lower when the silicon nPs are used in the brazing process.

关键词： Brazing nanoparticles Silicon Stainless steel