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Agro-Industrial Waste as a Source of Raw Material:Eggshell and Ash of Agave salmiana Useful for the Synthesis of Hydroxyapatite

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Journal of Renewable Materials 2022年第12期10卷 3559-3572页

作者： nora Elizondo-Villarreal Luz HVerástegui-Dominguez Jose JQuijano-Briones Francisco JVázquez-Rodríguez Eden Rodríguez-Castellanos Enrique López-Cuellar Ernesto Torres-Lopez Victor MCastaño-Meneses Universidad Autónoma de nuevo León Facultad de Ciencias Fisico MatemáticasCiudad UniversitariaSan Nicolás de los GarzaNuevo LeónMéxico Universidad Autónoma de nuevo León Facultad de ArquitecturaCiudad UniversiariaSan Nicolás de los GarzaNuevo LeónMéxico Universidad Autónoma de nuevo León Facultad de Ingeniería Mecainicay EléctricaCiudad UniversitariaSan Nicolás de los GarzaNuevo LeónMéxico centro de Física aplicada y Tecnología Avanzada Universidad Nacional Autonoma de MéxicoQuerétaroMéxico

Agave salmiana ash and poultry eggshell powder as CaO sources were used for obtaining nanostructured hydro-xyapatite(HAP).The synthesis was carried out by the Green Chemistry Hydrothermal Biosynthesis at 180℃ with a pH of 5,by reacting CaO from Agave Salmiana ash and Eggshell powder,with dibasic caldium phosphate(CaH-PO_(4)+2H_(2)O)in an aqueous solution,with Aloe barbadensis *** product was characterized by X-ray dif-fraction,Fourier transform infrared spectroscopy(FT-IR),Scanning Electron Microscopy(SEM),and Transmission Electron Microscopy(TEM).The size and shape of the hydroxyapatite particles changed dramati-cally in the presence of Aloe *** crystals of Hydroxyapatite were observed when Eggshell powder and Agave salmiana ash were used as raw materials in the presence of the Aloe barbadensis *** with shapes of ribbons and plates from 1 micrometers to 8 micrometers were observed when using the eggshell powder in the presence of Aloe bar badensis and,in the case of Agave salmiana ash in the presence of Aloe bar-badensis,crystals with shapes of quadra ngular prisms and hexagonal(polyhedra)with sizes from 2 micrometers to 20 micrometers were *** was therefore successfully biosynthesized by a green and sus-tainable method that reduces the environmental impact.

关键词： Hydroxyapatite raw materials Agave salmiana eggshell Aloe barbadensis surfactant

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

Distribution of Malpighia mexicana in Mexico and its implications for Barranca del Río Santiago

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Journal of Forestry Research 2021年第3期32卷 1095-1103页

作者： Martín Tena Meza Rafael Manavarro-Cerrillo Diego Brizuela Torres Instituto de Botánica Centro Universitario de Ciencias Biológicas y AgropecuariasUniversidad de GuadalajaraMéxicoCamino Ramón Padilla Sánchez No.2100.Nextipac45200 ZapopanJaliscoMexico depto.ingeniería Forestal Laboratorio de SelviculturaDendrocronología y Cambio ClimáticoDendrodatLab-ERSAFUniversidad de CórdobaCampus de RabanalesCtra.N-IVkm.39614071 CórdobaSpain departamento de Producción Forestal Centro Universitario de CienciasBiológicas y AgropecuariasUniversidad de GuadalajaraMéxicoCamino Ramón Padilla Sánchez No.2100 Nextipac45200 ZapopanJaliscoMexico

Wild plants represent relatively unexplored resource of high economic potential,especially as an alternative to developing new crops and,even more relevant,for improving existing crops and contributing to nutrition and *** wild species M alpighia mexicana(manzanita)has a wide tradition of food,medicinal and ornamental use in *** is part of the American-origin group of tropical shrubs that produce edible red fruits,such as A cerola,which is considered the most important natural source of vitamin C in the *** the role played by *** in Mexico,and particularly in Barranca del Río Santiago(Santiago River Canyon),we modelled its potential distribution in both geographical *** used species'records from databases,local herbaria and records collected by the authors as well as climatic variables representing long term average,variability and extreme conditions of temperature and *** fit the models we used the modelling algorithm Maxent and selected an adequate configuration by testing a range of model complexity *** results indicate a clear species preference for warm-dry tropical forest,most extensively in the Balsas river depression and the central valleys of *** probability of the species presence in the western region was also high,although the probability was also high for smaller surface areas,such as the region of Santiago river canyons,which are covered by warm-dry tropical forests.

关键词： Malpighia mexicana Maxent Warmdry tropical forest Río Santiago Genetic resources Ecological niche model Manzanita

Induction of IgA and sustained deficiency of cell proliferative response in chronic hepatitis C

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World Journal of Gastroenterology 2008年第44期14卷 6844-6852页

作者： yalena Amador-Caizares Liz Alvarez-Lajonchere Ivis Guerra Ingrid Rodríguez-Alonso Gillian Martínez-Donato Julián Triana Eddy E González-Horta Angel Pérez Santiago Dueas-Carrera centro de ingeniería Genética y Biotecnología Ave 31e/ 158 and 190PlayaP.O. Box 6162HavanaCuba

AIM： In the present study, antibody and peripheral blood mononuclear cells （PBMC） proliferative responses against hepatitis C virus （HCV） antigens were evaluated in HCV chronically infected patients. METHODS： Paired serum and PBMC samples were taken six months apart from 34 individuals, either treated or not, and tested by enzyme-linked immunosorbent assay （ELISA） and carboxyfluorescein succinimidyl ester staining. RSULTS： Over 70% of the patients showed specific IgG and IgM against capsid, E1 and nS3, while HVR-1 was recognized by half of the patients. An increase in the levels of the anti-capsid IgM （P = 0.027） and IgG （P = 0.0006） was observed in six-month samples, compared to baseline. Similarly, a significantly higher percent of patients had detectable IgA reactivity to capsid （P = 0.017） and nS3 （P = 0.005） after six months, compared to baseline. Particularly, IgA against structural antigens positively correlated with hepatic damage （P = 0.036）. IgG subclasses evaluation against capsid and nS3 revealed a positive recognition mediated by IgG1 in more than 80% of the individuals. On the contrary, less than 30% of the patients showed a positive proliferative response either of CD4＋ or CD8＋ T cells, being the capsid poorly recognized. COnCLUSIOn： These results confirm that while the cellular immune response is narrow and weak, a broad and vigorous humoral response occurs in HCV chronic infection. The observed correlation between IgA and hepatic damage may have diagnostic significance, although it warrants further confirmation.

关键词： Hepatitis C Antibody response Lymphoproliferation Core Envelope

Synthesis and characterization of La ni_xCo_(1–x)O_3: Role of microstructure on magnetic properties

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Journal of Rare Earths 2015年第3期33卷 277-281页

作者： L.Chávez-Guerrero B.Medina-Lott R.F.Cienfuegos M.A.Garza-navarro R.n.Vannier A.Ringuedé M. Hinojosa M.Cassir Universidad Autónoma de nuevo León FIME. Cd. Universitaria San Nicolás de los Garza México C.P. 66450 México Laboratoired’Electrochimie et de Chimie Analytique UMR 7575 CNRS Chimie Paris Tech ENSCP 11 rue Pierre et Marie Curie F-75231 Paris Cedex 05 France centro de Innovación Investigación y Desarrollo en Ingeniería y Tecnología PIIT Monterrey México Unité de Catalyse et de Chimie du Solide UMR 8181 CNRS Villeneuve d’Ascq France

Perovskite-type structures with the composition La ni x Co1–x O3（x=0.3, 0.5, 0.7） were synthesized by a modified sol-gel method. Using transitional metal elements on the lanthanum base perovskites, properties could be tuned by doping the structure. Thermogravimetric analysis（TGA） evidenced a temperature of 350 °C as the start point of the perovskite-phase formation. Scanning electron microscopy（SEM） images showed the microstructure changes（grain size） of the cobalt-doped perovskite due to composition. In addition, it was shown that magnetic properties of the samples were dependent of cobalt content; experimental results pointed to the existence of disordered spins interactions, which were more evident with the decrease of cobalt content and the existence of ferromagnetic coupling among spins of the samples. These results showed the feasibility of producing a family of compounds with the desired properties, manipulating composition and therefore the microstructure.

关键词： Co-doped perovskite microstructural control modified sol-gel ferromagnetic rare earths

The reversed intra- and extracellular pH in tumors as a unified strategy to chemotherapeutic delivery using targeted nanocarriers

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Acta Pharmaceutica Sinica B 2021年第8期11卷 2243-2264页

作者： Edgar Pérez-Herrero Alberto Fernández-Medarde departamento de ingeniería Química y Tecnología Farmacéutica Universidad de La LagunaLa Laguna 38206TenerifeSpain Instituto Universitario de Bio-Orgánica Antonio González Universidad de La LagunaLa Laguna 38206TenerifeSpain Instituto Universitario de Tecnologías Biomédicas Universidad de La LagunaLa Laguna 38200TenerifeSpain Instituto de Biología Molecular y Celular del Cáncer Centro de Investigación Del Cáncer(USAL-CSIC)Salamanca 37007Spain

Solid tumors are complex entities,comprising a wide variety of malignancies with very different molecular *** this,they share a set of characteristics known as"hallmarks of cancer"that can be used as common therapeutic ***,every tumor needs to change its metabolism in order to obtain the energy levels required for its high proliferative rates,and these adaptations lead to alterations in extra-and intracellular *** changes in p H are common to all solid tumors,and can be used either as therapeutic targets,blocking the cell proton transporters and reversing the pH changes,or as means to specifically deliver anticancer *** this review we will describe how proton transport inhibitors in association with nanocarriers have been designed to block the pH changes that are needed for cancer cells to survive after their metabolic *** will also describe studies aiming to decrease intracellular pH in cancer using nanoparticles as molecular cages for protons which will be released upon UV or IR light ***,we will comment on several studies that have used the extracellular pH in cancer for an enhanced cell internalization and tumor penetration of nanocarriers and a controlled drug delivery,describing how nanocarriers are being used to increase drug stability and specificity.

关键词： pH-Gradient inversion Metabolism of glucose Proton transport inhibitors Proton-caged carriers Chemotherapy Targeted drug delivery pH-Sensitive nanocarriers Warburg effect Cancer

Corrosion Behavior of Ψ and β Quasicrystalline Al–Cu–Fe Alloy

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Acta Metallurgica Sinica(English Letters) 2015年第9期28卷 1117-1122页

作者： Alvaro Torres Sergio Serna Cristobal Patio Gerardo Rosas Facultad de ciencias Químicas e ingeniería P.A. Ing.Mecnica UAEM Av. Universidad 1001 Col. Chamilpa62210 Cuernavaca Mor. Mexico centro de investigación en ingeniería y ciencias aplicadas UAEM Av. Universidad 1001 Col. Chamilpa62210 Cuernavaca Mor. Mexico Facultad de ingeniería Universidad Autónoma del CarmenCampus Ⅲ Avenida Central S/N Esq. con Fracc. MundoMaya C.P. 24115 Ciudad del Carmen Campeche Mexico Instituto de investigaciones Metalurgicas UMSNH Edificio U. Ciudad Universitaria Morelia Mich. 58000 Mexico

Two nanostructured A1-Cu-Fe alloys, A164Cu24Fe12 and A162.5Cu25.2Fe12.3, have been studied. Icosahedral quasicrystalline （ψ） A164CH24FeI2 and crystalline cubic （ β） ***25.2Fe12.3 cylindrical ingots were first produced using normal casting techniques. High-energy mechanical milling was then conducted to obtain β icosahedral and β intermetallic nanostructured powders. Electrochemical impedance spectroscopy, linear polarization resistance, and potentiodynamic polarization were used to investigate the electrochemical corrosion characteristics of the powders in solutions with different pH values. Current density （icorr）, polarization resistance （Rp）, and impedance modulus （121） were determined. The results showed that regardless of pH value, increasing the solution temperature enhanced the corrosion resistance of the both phases. However, the electrochemical behavior of the phase indicated that its stability depends on the submerged exposure time in neutral and alkaline environments. This behavior was related to the type of corrosion products present on the surfaces of the particles along with the diffusion and charge-transfer mechanisms of the corrosion process.

关键词： nano-quasicrystalline AI-Cu-Fe alloy Mechanical alloying Corrosion

Synthesis of novel Hexathiolated Squalene and Its Thiol-Ene Photopolymerization with Unsaturated Monomers

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Green and Sustainable Chemistry 2012年第2期2卷 62-70页

作者： Ricardo Acosta Ortiz Ena Adeligna Obregón Blandón Ramiro Guerrero Santos centro de investigación en Química aplicada Saltillo México Universidad nacional de ingeniería Avenida Universitaria Managua Nicaragua

In this work is described the synthesis of a multifunctional thiolated squalene. Thiol-ene coupling reactions were employed to functionalize the six double bonds of squalene, using thiolacetic acid. Hydrolysis of the resulting thioacetates, rendered the corresponding hexathiolated squalene SQ6SH. This compound was further photopolymerized separately with triallyl cyanurate, pentaerythritol triacrylate and diethyleneglycol divinyl ether. Real Time FTIR kinetics revealed that homopolymerization of the ene monomers took place in addition to the thiol-ene photopolymerization. Flexible films were obtained when SQ6SH was photopolymerized in bulk with the above mentioned unsaturated monomers.

关键词： Squalene Thiol-Ene Photopolymerization Biomaterials Kinetics

Optical properties of phosphate glasses co-doped with yb^(3+) and silver nanoparticles

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Chinese Physics B 2014年第12期23卷 249-253页

作者： M.A.Vallejo H. M.A.Martinez G. A.V.Kiryanov J.L.Lucio M. centro de investigaciones enóptica Loma del Bosque 115 Col.Lomas del CampestreLeón 37150 Guanajuato Mxico División de ciencias e ingenierías del Campus León de la Universidad de Guanajuato Loma del Bosque 103Col.Lomas del Campestre37150León Guanajuato Mxico

We report the fabrication and spectroscopic characterization of yb^3＋-doped phosphate glass, also containing silver nitrate. Scanning electron microscopy（SEM） provides the evidence of the formation of silver nano-particles（SnPs）, which are formed as a consequence of melting and thermal decomposition of Ag nO3. Absorption spectra of the samples in the visible-to-near-infrared spectral range reveal the presence of bands centered at 410 nm associated with the SnP-plasmon resonance, and at 976 nm due to the yb^3＋. Under 916-nm laser-diode pumping, the effect of the SnP reflects that： i） the fluorescence in the 950-nm–1150-nm spectral range is strongly enhanced（～ 30 times）, while the fluorescence decay time associated with the ^2F5/2→^2F7/2transition of yb^3＋ increases 25%, and ii） the basic lasing properties（saturation pumping intensity, the emission and absorption cross sections） are substantially improved.

关键词： rare earths phosphate glasses silver nanoparticles