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EnVIROnMEnTAL ISSUES RELATED TO EnHAnCED PRODUCTIOn OF nATURAL GAS BY HYDRAULIC FRACTURInG

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Journal of Green Building 2013年第1期8卷 62-71页

作者： John Walton Arturo Woocay University of Texas at El Paso división de estudios de posgrado e Investigación Instituto Tecnológico de Ciudad JuárezAve

InTRODUCTIOn Hydraulic fracturing occurs when high pressure fluids primarily consisting of water and sand are pumped at high pressure into subsurface formations,typically shale that contains natural gas and/or *** high pressure fluid causes the rock to *** new fractures increase the surface area of the shale and better interconnect previously existing fractures,allowing more natural gas and/or oil to be pumped from the *** hydraulic fracturing,referred to as“fracking,”is an evolving technology that largely began after 2000 and has significantly increased natural gas production in the United States in the past five years with corresponding decreases in natural gas prices.

关键词： environmental impact fracking land use and disturbance water and groundwater contamination hydraulic fracturing risk drilling

Maize seed coatings and seedling sprayings with chitosan and hydrogen peroxide:their influence on some phenological and biochemical behaviors

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2013年第2期14卷 87-96页

作者： Eva-Guadalupe LIZRRAGA-PAULín Susana-Patricia MIRAnDA-CASTRO Ernesto MOREnO-MARTínEZ Alma-Virginia LARA-SAGAHón Irineo TORRES-PACHECO Laboratorio de Biotecnología Facultad de Estudios Superiores CuautitlánCampo 1Universidad Nacional Autónoma de MéxicoEstado de México 54740México Unidad de Investigación en Granos y Semillas Facultad de Estudios Superiores CuautitlánCentro de Asimilación TecnológicaUniversidad Nacional Autónoma de MéxicoEstado de México 54740México CA Ingeniería de Biosistemas División de Investigación y PosgradoFacultad de IngenieríaUniversidad Autónoma de QuerétaroQuerétaro 76010México

Objective： To evaluate the effect of chitosan （CH） and hydrogen peroxide （H2O） seed coatings and seedling sprinklings on two different maize varieties by measuring their phenology, the H202 presence, the catalase （CAT） activity, and the protein quantity. Methods： Seven groups of ten seeds for each maize variety were treated with CH （2% （20 g/L） and 0.2% （2 g/L）） or H2O2 （8 mmol/L） by coating, sprinkling, or both. Germination and seedling growth were measured. One month after germination, the presence of H202 in seedlings in the coated seed treatments was evaluated. Protein content and CAT activity were determined under all treatments. Results： H2O2 seed coating en- hanced the germination rate and increased seedling and stem length in the quality protein maize （QPM） variety. Seedlings had a higher emergence velocity under this treatment in both varieties. CH and H2O2 sprinklings did not have an effect on seedling phenology. Exogenous application of H2O2 promoted an increase of endogenousH2O2. OH and H2O2seedling sprinkling increased the protein content in both maize varieties, while there was no significant effect on the CAT activity of treated seeds and seedlings. Conclusions： CH and H2O2 enhance some phenological and biochemical features of maize depending on their method of application.

关键词： Zea mays Chitosan Hydrogen peroxide Phenology Catalase Protein

Pulsatile electroosmotic flow of a Maxwell fluid in a parallel flat plate microchannel with asymmetric zeta potentials

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Applied Mathematics and Mechanics(English Edition) 2018年第5期39卷 667-684页

作者： M.PERALTA O.BAUTISTA F.MEndeZ E.BAUTISTA Seccion de estudios de posgrado e Investigacion ESIME Azcapotzalco Instituto Politecnico NacionalCiudad de Mexico 02250Mexico Facultad de Ingeniería Universidad Nacional Autonoma de MexicoCiudad de Mexico 04510Mexico

The pulsatile electroosmotic flow （PEOF） of a Maxwell fluid in a parallel flat plate microchannel with asymmetric wall zeta potentials is theoretically analyzed. By combining the linear Maxwell viscoelastic model, the Cauchy equation, and the electric field solution obtained from the linearized PoissomBoltzmann equation, a hyperbolic par- tial differential equation is obtained to derive the flow field. The PEOF is controlled by the angular Reynolds number, the ratio of the zeta potentials of the microchannel walls, the electrokinetic parameter, and the elasticity number. The main results obtained from this analysis show strong oscillations in the velocity profiles when the values of the elas- ticity number and the angular Reynolds number increase due to the competition among the elastic, viscous, inertial, and electric forces in the flow.

关键词： pulsatile electroosmotic flow (PEOF) flat plate microchannel asymmetric zeta potential Maxwell fluid

Polyphenols as potential enhancers of stem cell therapy against neurodegeneration

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neural Regeneration Research 2022年第10期17卷 2093-2101页

作者： Diana Rodríguez-Vera Antonio Abad-García nancy Vargas-Mendoza Rodolfo Pinto-Almazán Eunice D.Farfán-García José A.Morales-González Marvin A.Soriano-Ursúa Sección de estudios de posgrado e Investigación.Escuela Superior de Medicina Instituto Politécnico NacionalMéxico CityMéxico Unidad de Investigación Hospital Regional de Alta Especialidad IxtapalucaCarretera Federal México-Puebla km 34.5State of MéxicoMéxico

The potential of polyphenols for treating chronic-degenerative diseases(particularly neurodegenerative diseases)is ***,the selection of the best polyphenol for each treatment,the mechanisms by which they act,and their efficacy are frequently *** this review,the basics and the advances in the field,as well as suggestions for using natural and synthetic polyphenols alone or in a combinatorial strategy with stem cell assays,are compiled and ***,stem cells exhibit several responses when polyphenols are added to their environment,which could provide us with knowledge for advancing the elucidation of the origin of *** also,polyphenols are being included in the innovative strategies of novel therapies for treating neurodegenerative diseases as well as metabolic diseases related to *** this regard,flavonoid compounds are suggested as the best natural polyphenols due to their several mechanisms for acting in ameliorative effects;but increasing reports are involving other *** if some facts limiting bioactivity prevent them from conventional use,some natural polyphenols and derivatives hold the promise for being improved compounds,judged by their induced *** current results suggest polyphenols as enhancers of stem cell therapy against the targeted diseases.

关键词： Alzheimer’s disease chronic degenerative diseases combinatorial therapy metabolism neurodegenerative diseases neuronal damage neuroprotection Parkinson’s disease polyphenols stem cell assays

Biocompatibility and electrochemical evaluation of ZrO_(2) thin films deposited by reactive magnetron sputtering on MgZnCa alloy

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Journal of Magnesium and Alloys 2021年第6期9卷 2019-2038页

作者： Benjamín Millán-Ramos Daniela Morquecho-Marín Phaedra Silva-Bermudez David Ramírez-Ortega Osmary depablos-Rivera Julieta García-López Mariana Fernández-Lizárraga JoséVictoria-Hernández Dietmar Letzig Argelia Almaguer-Flores Sandra E.Rodil Instituto de Investigaciones en Materiales Universidad Nacional Autónoma de MéxicoCDMX 04510Mexico posgrado en Ciencia e Ingeniería de Materiales Universidad Nacional Autónoma de MéxicoCDMX 04510Mexico Unidad de Ingeniería de Tejidos Terapia Celular y Medicina RegenerativaInstituto Nacional de Rehabilitación Luis Guillermo IbarraCDMX 14389Mexico posgrado en Ciencias Médicas Odontológicas y de la SaludUniversidad Nacional Autónoma de MéxicoCDMX 04510Mexico Instituto de Ciencias Aplicadas y Tecnologia Universidad Nacional Autónoma de MéxicoCDMX 04510Mexico posgrado de Doctorado en Ciencias en Biomedicina y Biotecnología Molecular Escuela Nacional de Ciencias BiológicasInstituto Politécnico NacionalCDMX 11340Mexico Institute of Material and Process design Helmholtz-Zentrum GeesthachtMax-Planck-Strasse 1Geesthacht 21502Germany Magnesium Innovation Centre MagIC Helmholtz-Zentrum GeesthachtMax-Planck-Strasse 1Geesthacht 21502Germany Laboratorio de Biointerfases Facultad de OdontologíaDivisión de Estudios de Posgrado e InvestigaciónUniversidad Nacional Autónoma de MéxicoCDMX 04510Mexico

Biodegradable magnesium alloys are promising candidates for temporary fracture fixation devices in orthopedics;nevertheless,its fast degradation rate at the initial stage after implantation remains as one of the main challenges to be ***_(2)-based coatings to reduce the degradation rate of the Mg-implants are an attractive solution since they show high biocompatibility and *** this work,the degradation,cytotoxicity,and antibacterial performance of ZrO_(2)thin films deposited by magnetron sputtering on a Mg-Zn-Ca alloy was ***-term degradation of ZrO_(2)-coated and uncoated samples was assessed considering electrochemical techniques and H_(2)evolution(gas chromatography).Additionally,long term degradation was assessed by mass-loss *** results showed that a 380 nm ZrO_(2)coating reduces the degradation rate and H_(2)evolution of the alloy during the initial 3 days after immersion but allows the degradation of the bare alloy for the *** ZrO_(2)coating does not compromise the biocompatibility of the alloy and permits better cell adhesion and proliferation of mesenchymal stem cells directly on its surface,in comparison to the bare ***,the ZrO_(2)coating prevents the adhesion and biofilm formation of ***.

关键词： Zirconium dioxide Magnetron sputtering Short-term degradation H_(2)evolution

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

Solid Lipid nanoparticles (SLn) and nanostructured Lipid Carriers (nLC): Occlusive Effect and Penetration Enhancement Ability

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Journal of Cosmetics, dermatological Sciences and Applications 2015年第2期5卷 62-72页

作者： R. López-García A. Ganem-Rondero división de estudios de posgrado (Tecnología Farmacéutica) Facultad de Estudios Superiores Cuautitlán Universidad Nacional Autónoma de México Cuautitlán Izcalli Mexico

Objective: This work compares the occlusive effect and the penetration enhancement ability of solid lipid nanoparticles (SLn) and nanostructured lipid carriers (nLC), through in vitro skin. Methods: SLn and nLC were prepared by high shear homogenization and characterized by size, polydispersity index, zeta potential, morphology and physical stability. Occlusive effect was assessed by an in vitro test and by measuring TEWL using pig skin. Skin treated with the lipid carriers was visualized by SEM. A penetration test through skin, followed by tape stripping, was carried out using nile red as a marker. Results: SLn (200 ± 6 nm) and nLC (192 ± 11 nm) were obtained. An occlusion factor of 36% - 39% was observed for both systems, while a reduction in TEWL of 34.3% ± 14.8% and 26.2% ± 6.5% was seen after treatment with SLn and nLC, respectively. SEM images showed a film formed by the lipid carriers, responsible for the occlusion observed. no differences were found between the occlusive effect produced by SLn and nLC in both tests. nLC allowed the penetration of a greater amount of nile red than SLn: 4.7 ± 1.3 μg and 1.7 ± 0.4 μg, respectively. Conclusion: Both carriers form a film on the skin, providing an occlusive effect with no differences between these two systems. The penetration of a marker (nile red) into the stratum corneum was quite higher for nLC than for SLn, suggesting an influence of the composition of these particles on their penetration enhancing ability.

关键词： Solid Lipid nanoparticles nanostructured Lipid Carriers Occlusive Effect Transepidermal Water Loss Skin Penetration

Generation and Control of Turbulences in a Wind Tunnel

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Open Journal of Fluid Dynamics 2016年第4期6卷 453-471页

作者： América Torres Roberto Tapia Antonio Ramos división de estudios de posgrado Facultad de Ingeniería Eléctrica Universidad Michoacana de San Nicolás de Hidalgo Morelia México

In this paper, the generation and control of turbulences in a wind tunnel, for design, analysis and testing of test objects are proposed. Modifications to the wind tunnel are made in order to generate the turbulences in the test chamber. Specifically, for the turbulence analysis, the reflective symmetry concept is used in order to group the different turbulences cases generated in the wind tunnel test chamber. The Ansys software is used in order to model and analyze the wind tunnel. Specific platform or module known as Fluent is used for the analysis of the turbulence generated in the wind tunnel. To design proposal of a wind tunnel capable to generate and controlling turbulences is exposed in this paper. For this, the controller design and verification are performed by means of simulations. To obtain the control law structure, the inversion concept is used. The proposed control law is validated via a co-simulation implemented in the Simplorer module, with the aim of combining the power electronics part, controller and engine, with the proposed model wind tunnel.

关键词： Wind Tunnel Turbulence Control

Strategies for the Extraction, Purification and Amplification of Metagenomic DnA from Soil Growing Sugarcane

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Advances in Biological Chemistry 2014年第4期4卷 281-289页

作者： Luis Raúl Gutiérrez-Lucas Juan José Montor-Antonio nohemí Gabriela Cortés-López Sandra del Moral división de estudios de posgrado Universidad del Papaloapan Tuxtepec México Instituto de Biotecnología. Universidad del Papaloapan Tuxtepec Oaxaca México

Recently, studies were initiated to investigate the metagenome, which represents the genomes of cultured and uncultured microbes, as a rich source for isolation of many novel genes. The meta-genomic approach originated from the molecular analysis of microbial communities, which revealed that the majority of microorganisms in nature were not cultivable by standard culturing techniques. Therefore, most microorganisms in nature have not been characterized. Although numerous methods have been reported for direct DnA isolation and purification from microorganisms in soil, the sample preparation procedures and experimental conditions used in different studies vary widely. Soils are therefore one of the most challenging environmental matrices from which to obtain microbial DnA that will support PCR. The Papaloapan River is the second largest river basin in México. For the climatic conditions of this region, there is great diversity in plants, animals and microorganisms. In the Papaloapan region different fruits are grown, however, the main crops are sugarcane and pineapple. In this work the extraction of DnA from soils of sugarcane cultivation was performed. We used PCR tests to assess the quality of DnA extracted from soil by amplifying the 16S rDnA gene. Changes in both protocols were performed;satisfactory results were obtained as to the quality of DnA and gene amplification. These results will allow continuing the metagenomic studies, such as sequencing, library construction and identification of enzymes cellulase and amylase activity. It is the first time these studies were performed in the Papaloapan region.

关键词： Metagenomic Soil DnA Metagenome Papaloapan Basin