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Active compounds of medicinal plants,mechanism for antioxidant and beneficial effects

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Phyton-International Journal of Experimental Botany 2019年第1期88卷 1-10页

作者： Orozco Montes F a vázquez-hernández B Fenton-Navarro Glycobiology Laboratory Postgraduate Studies DivisionFaculty of Medicine and Biological Sciences“Dr.Ignacio Chávez”Michoacán University of Saint Nicholas of Hidalgo(UMSNH)MoreliaMichoacánMexico Hospital of Specialties CMN SXXIIMSSMéxico CityMéxico

An increased interest in the antioxidant effects of medicinal plants has developed in recent *** antioxidant compounds present in medicinal plants and elucidating the mechanism by which they prevent oxidation have been the focus of the research *** performed a systematic and exhaustive review aimed at analyzing the available data regarding the beneficial effects of secondary metabolites in *** result of this review is presented as a description of free radicals,as well as cellular and physiological oxidative stress,is *** origin and source of antioxidant compounds,and the cellular and molecular mechanism by which they exert antioxidant effects,have been *** absorption,distribution and,elimination of antioxidants are *** beneficial effects of secondary metabolites of medicinal plants in various high incidence disease conditions were also ***,disease states that benefit from antioxidant compounds includes diabetes,cancer,cardiovascular diseases,and liver,brain and,intestinal diseases.

关键词： Antioxidants Free radicals Secondary metabolites Polyphenols Oxidative stress Medicinal plants

Antioxidant,anti-inflammatory and antinociceptive potential of Ternstroemia sylvatica Schltdl.&Cham

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Asian Pacific Journal of Tropical Medicine 2017年第11期10卷 1047-1053页

作者： Claudia v.Moreno-Quirós Alberto Sánchez-Medina Maribel vázquez-hernández Ana G.hernández Reyes Rosa v.García-Rodríguez Unidad de Servicios de Apoyo en Resolución Analítica Universidad VeracruzanaXalapaVeracruzMexico

ObjectiveTo evaluate the anti-inflammatory, analgesic, antioxidant and acute toxicity of extracts obtained from a successive extraction with solvents of ascending polarity [hexane, hex; chloroform, CHCl3 and ethanol (EtOH)] of Ternstroemia sylvatica Schltdl. & *** antioxidant potential was evaluated by 2,2 diphenyl-1-picrylhydrazyl, the ferric reducing/antioxidant power assays and by determining the total phenolic content. The anti-inflammatory and antinociceptive effects were evaluated using the in vivo croton oil-induced ear edema, phorbol 12-myristate 13-acetate induced ear edema, carrageenan-induced paw edema, acetic acid-induced writhing and formalin murine models. The acute toxicity was tested using the Lorke’s method in *** EtOH extract was the most active for the antioxidant potential tests diphenyl-1-picrylhydrazyl (68.70% inhibition), ferric reducing/antioxidant power [(2 431.30 ± 102.10) mmol Fe2+ and total polyphenols content (215.80 ± 8.50) meqAG/g]. The anti-inflammatory activity was evaluated by topical application of croton oil (2 mg/ear dose) where the EtOH extract showed the strongest activity compared to the control group (45.13% inhibition), whereas in the phorbol 12-myristate 13-acetate model, at the same dose, the CHCl3 extract showed the highest inhibition (42.88%). In the carrageenan induced edema model, the EtOH extract showed a stronger inhibition compared to indomethacin (56.34% and 50.70% at doses of 250 and 500 mg/kg of extract, respectively) during the first hour. Similarly, the same extract showed the highest analgesic activity (30.60% inhibition) in the acetic acid contortion assay, and in the formalin test it showed a greater effect with respect to the control group in both *** work confirms the value of Ternstroemia sylvatica as an important anti-inflammatory and analgesic plant, whose mechanism seems to be associated to its antioxidant effects, and supports

关键词： Ternstroemia sylvatica Anti-inflammatory Analgesic Medicinal plants

Targeting harmful effects of non-excitatory amino acids as an alternative therapeutic strategy to reduce ischemic damage

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Neural Regeneration Research 2025年第9期20卷 2454-2463页

作者： victoria Jiménez Carretero IrisÁlvarez-Merz Jorge hernández-Campano Sergei A.Kirov Jesús M.hernández-Guijo Department of Pharmacology and Therapeutic School of MedicineUniv.Autónoma de MadridMadridSpain Ramón y Cajal Institute for Health Research(IRYCIS) Neurobiology-Research ServiceHospital Ramón y CajalMadridSpain Institute of Neurobiology Faculty of Mathematics and Natural SciencesHeinrich Heine University DüsseldorfDüsseldorfGermany Department of Neuroscience and Regenerative Medicine&Department of Neurosurgery Medical College of Georgia at Augusta UniversityAugustaGAUSA

The involvement of the excitatory amino acids glutamate and aspartate in ce rebral ischemia and excitotoxicity is ***,the role of non-excitatory amino acids in brain damage following a stroke or brain trauma remains largely *** release of amino acids by necrotic cells in the ischemic core may contribute to the expansion of the *** findings indicated that the reversible loss of field excitato ry postsynaptic potentials caused by transient hypoxia became irreversible when exposed to a mixture of just four non-excitatory amino acids(L-alanine,glycine,L-glutamine,and L-serine)at their plasma *** amino acids induce swelling in the somas of neurons and astrocytes during hypoxia,along with permanent dendritic damage mediated by N-methyl-D-aspartate *** N-methyl-D-aspartate receptors prevented neuronal damage in the presence of these amino acids during *** is likely that astroglial swelling caused by the accumulation of these amino acids via the alanine-serine-cysteine transporter 2 exchanger and system N transporters activates volume-regulated anion channels,leading to the release of excitotoxins and subsequent neuronal damage through N-methyl-D-aspartate receptor ***,previously unrecognized mechanisms involving non-excitatory amino acids may contribute to the progression and expansion of brain injury in neurological emergencies such as stroke and traumatic brain *** these pathways co uld highlight new therapeutic targets to mitigate brain injury.

关键词： cell swelling N-methyl-D-aspartate receptor non-excitatory amino acids stroke synaptic transmission

Effect of initial microstructure on austenite formation kinetics in high-strength experimental microalloyed steels

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International Journal of Minerals,Metallurgy and Materials 2015年第12期22卷 1304-1312页

作者： Edgar López-Martínez Octavio vázquez-Gómez Héctor Javier vergara-hernández Bernardo Campillo Faculty of Chemistry Metallurgical Engineering Department Autonomous National University of Mexico National Council for Science and Technology Metallurgy Science Postgraduate Programme Morelia Institute of Technology Institute of Physical Sciences Autonomous National University of Mexico

Austenite formation kinetics in two high-strength experimental microalloyed steels with different initial microstructures comprising bainite-martensite and ferrite-martensite/austenite microconstituents was studied during continuous heating by dilatometric analysis. Austenite formation occurred in two steps：（1） carbide dissolution and precipitation and （2） transformation of residual ferrite to austenite. Dilatometric analysis was used to determine the critical temperatures of austenite formation and continuous heating transformation diagrams for heating rates ranging from 0.03°C.s^-1 to 0.67°C.s^-1. The austenite volume fraction was fitted using the Johnson-Mehl-Avrami-Kolmogorov equation to determine the kinetic parameters k and n as functions of the heating rate. Both n and k parameters increased with increasing heat- ing rate, which suggests an increase in the nucleation and growth rates of austenite. The activation energy of austenite formation was determined by the Kissinger method. Two activation energies were associated with each of the two austenite formation steps. In the first step, the austenite growth rate was controlled by carbon diffusion from carbide dissolution and precipitation; in the second step, it was controlled by the dissolution of residual ferrite to austenite.

关键词： non-isothermal kinetics microalloyed steel austenite heating dilatometry

Habitat use and space preferences of Eurasian Bullfinches(Pyrrhula pyrrhula)in northwestern Iberia throughout the year

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Avian Research 2021年第1期12卷 37-51页

作者： Angel hernández Departamento de Ciencias Agroforestales Area de ZoologiaUniversidad de ValladolidCampus de PalenciaPalenciaEspana Instituto Universitario de Investigacion en Gestion Forestal Sostenible Universidad de ValladolidCampus de PalenciaPalenciaEspana

Background:For all vertebrates in general,a concerted effort to move beyond single season research is vital to improve our understanding of species *** of habitat use and selection by Eurasian Bullfinches(Pyrrhula pyrrhula)is limited with regard to the non-breeding *** date,research on the habitat of the Iberian subspecies iberiae consists of very general *** relation to space use,only broad features are available for the entire distribution range of Eurasian Bullfinches,including ***:In this study,seasonal preferences regarding habitat and space in a population of Eurasian Bullfinches are examined for the first time in the Iberian Peninsula,through direct observation during a six-year *** essential habitat components,substrate selection and perch height were ***:Hedgerows were the key essential habitat component for bullfinches during all ***,small poplar plantations became increasingly important from winter to *** perched mostly in shrubs/trees throughout the year,but there were significant seasonal changes in substrate use,ground and herbs being of considerable importance during *** the year,over half of the records corresponded to feeding,reaching almost 90%in ***,bullfinches perched noticeably lower while *** bullfinches perched markedly higher than females,notably singing males in *** perched at a height not much lower than that of *** all seasons,males tended to feed at greater heights than *** of different ages and sexes were seen bathing in all seasons except ***:Hedgerow habitat in general appeared to be valuable for bullfinches throughout the *** summer and autumn,they selected sites with an abundance of food and shade,as well as shelter,a much-needed requirement for fledglings and moulting *** was usually a close link between the most used

关键词： Habitat use Perch height Pyrrhula pyrrhula iberiae Seasonal variation Substrate selection Water bathing

Highly graphitized carbon nanosheets with embedded Ni nanocrystals as anode for Li-ion batteries

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Nano Research 2020年第1期13卷 86-94页

作者： Francisco Javier Soler-Piña Celia hernández-Rentero Alvaro Caballero Julián Morales Enrique Rodríguez-Castellón Jesús Canales-vázquez Dpto.Química Inorgánica e Ingeniería Química Instituto de Química Fina y NanoquímicaUniversidad de Córdoba14071CórdobaSpain Dpto.Química Inorgánica Cristalografía y MineralogíaFacultad de CienciasUniversidad de Málaga29071MálagaSpain Instituto de Energías Renovables Universidad de Castilla-La ManchaPaseo de La Investigación 102071AlbaceteSpain

A C/Ni composite was prepared via thermal decomposition of a nickel oleate complex at 700℃,yielding disperse Ni nanocrystals with an average size of 20 nm,encapsulated by carbon nanosheets as deduced from transmission electron microscopy(TEM)images and confirmed from X-ray photoelectron spectroscopy(XPS).Furthermore,the X-ray diffraction pattern revealed a good ordering of the carbon layers,forced by the Ni encapsulation to adopt a bending *** the close interaction between the graphitized framework and the metallic nanoparticles we have studied the properties of the composite as an anode for Li-ion *** with other nanostructured synthetic carbons,this carbon composite has a low voltage hysteresis and a modest irreversible capacity value,properties that play a significant role in its behaviour as electrodes in full cell *** moderate rate values,0.25 C,the electrode delivers an average capacity value around 723 mAh·g^−1 on cycling,among the highest values so far reported for this carbon *** higher rate values,1 C,the average capacity values delivered by the cell on cycling decrease,around 205 mAh·g^−1,but it maintains good capacity retention,a coulombic efficiency close to 100%after the first cycles and recovery of the capacity values when the rate is restored from 3 to 0.1 C.

关键词： carbon nanosheets nickel nanoparticles anode lithium batteries

Modeling and multi-objective optimization of a gasoline engine using neural networks and evolutionary algorithms

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2013年第9期14卷 657-670页

作者： JoséD. MARTíNEZ-MORALES Elvia R. PALACIOS-hernández Gerardo A. vELázquez-CARRILLO Faculty of Engineering Autonomous University of San Luis PotosiSan Luis Potosi 78290 Mexico Faculty of Science Autonomous University of San Luis PotosiSan Luis Potosi 78290 Mexico Mechatronics Department Monterrey Institute of Technology and Higher EducationMexico D. F. 01389 Mexico

In this paper, a multi-objective particle swarm optimization （MOPSO） algorithm and a nondominated sorting genetic algorithm II （NSGA-II） are used to optimize the operating parameters of a 1.6 L, spark ignition （SI） gasoline engine. The aim of this optimization is to reduce engine emissions in terms of carbon monoxide （CO）, hydrocarbons （HC）, and nitrogen oxides （NOx）, which are the causes of diverse environmental problems such as air pollution and global warming. Stationary engine tests were performed for data generation, covering 60 operating conditions. Artificial neural networks （ANNs） were used to predict exhaust emissions, whose inputs were from six engine operating parameters, and the outputs were three resulting exhaust emissions. The outputs of ANNs were used to evaluate objective functions within the optimization algorithms： NSGA-II and MOPSO. Then a decision-making process was conducted, using a fuzzy method to select a Pareto solution with which the best emission reductions can be achieved. The NSGA-II algorithm achieved reductions of at least 9.84%, 82.44%, and 13.78% for CO, HC, and NOx, respectively. With a MOPSO algorithm the reached reductions were at least 13.68%, 83.80%, and 7.67% for CO, HC, and NOx, respectively.

关键词： Engine calibration Multi-objective optimization Neural networks Multiple objective particle swarm optimization(MOPSO) Nondominated sorting genetic algorithm II (NSGA-II)

Internal dispersal of seed-inhabiting insects by vertebrate frugivores:a review and prospects

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Integrative Zoology 2011年第3期6卷 213-221页

作者： Ángel hernÁndez Department of Agroforestry University of ValladolidPalenciaSpain

The finding that some seed-inhabiting insects can survive passage through the entire digestive tract of seed-dispersing vertebrates is relatively recent,but evidence suggests that it does ***,I document this phenomenon,discuss its qualitative and quantitative dimensions,and offer suggestions for further *** few documented cases that I review include plant species belonging to different families,with varied fleshy fruit types,number of seeds per fruit and seed *** vertebrate frugivores involved include passerines that feed on relatively small fruits,and galliforms,and perissodactyls and primates that feed on larger *** seed-inhabiting insects in-volved are the larvae of seed-infesting wasps,parasitoid wasps and seed-infesting *** phenomenon has been verified in open,rural ecosystems in North America and Southern Europe,and in tropical and subtropical forests in South *** varied scenarios suggest that the qualitative dimension of the phenomenon is considerably greater than known thus far.A simple method for detecting new events is ***,re-search must also focus on the identity and biology of seed-feeding insects of wild fleshy fruits and their *** survival rates of seed-inhabiting insects after vertebrate gut passage are *** phenomenon generally appears to favor insect dispersal.

关键词： digestion-resistant insects endozoochory frugivory tetratrophic interactions tritrophic interactions

Phylogeography and morphometric variation in the Cinnamon Hummingbird complex:Amazilia rutila(Aves:Trochilidae)

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Avian Research 2021年第4期12卷 509-525页

作者： Melisa vázquez-López Nandadevi Córtes-Rodríguez Sahid M.Robles-Bello Alfredo Bueno-hernández Luz E.Zamudio-Beltrán Kristen Ruegg Blanca E.hernández-Baños Museo de Zoología Facultad de CienciasUniversidad Nacional Autónoma de MéxicoApartado Postal04510 Mexico CityMexico Department of Biology Ithaca CollegeIthacaNY 14850USA Museo de Zoología Facultad de Estudios Superiores ZaragozaUniversidad Nacional Autónoma de MéxicoMexico CityMexico Department of Biology Colorado State UniversityFort CollinsCO 80523USA

Background:The Mesoamerican dominion is a biogeographic area of great interest due to its complex topography and distinctive climatic *** area has a large diversity of habitats,including tropical deciduous forests,which house a large number of endemic ***,we assess phylogeographic pattern,genetic and morphometric variation in the Cinnamon Hummingbird complex Amazilia rutila,which prefers habitats in this *** resident species is distributed along the Pacific coast from Sinaloa—including the Tres Marías Islands in Mexico to Costa Rica,and from the coastal plain of the Yucatán Peninsula of Mexico south to ***:We obtained genetic data from 85 samples of ***,using 4 different molecular markers(mtDNA:ND2,COI;nDNA:ODC,MUSK)on which we performed analyses of population structure(median-joining network,STRU CTU RE,FST,AMOvA),Bayesian and Maximum Likelihood phylogenetic analyses,and divergence time *** order to evaluate the historic suitability of environmental conditions,we constructed projection models using past scenarios(Pleistocene periods),and conducted Bayesian Skyline Plots(BSP)to visualize changes in population sizes over *** analyze morphometric variation,we took measurements of 5 morphological traits from 210 study *** tested for differences between sexes,differences among geographic groups(defined based on genetic results),and used PCA to examine the variation in multivariate ***:Using mtDNA,we recovered four main geographic groups:the Pacific coast,the Tres Marías Islands,the Chiapas region,and the Yucatán Peninsula together with Central *** same groups were recovered by the phylogenetic results based on the multilocus *** based on BSP results showed constant population size over time throughout the *** complex and within each geographic *** niche model projec-tions onto past scenarios revealed no drastic changes in suitable conditions,but revealed some

关键词： Amazilia rutila Genetic structure Genetic variation Phylogeography Tres Marías Islands Trochilidae Tropical deciduous forest