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Total Phenols,Flavonoids and Antioxidant Activity in Annona muricata and Annona purpurea Callus Culture

Phyton-International Journal of Experimental Botany 2019年第2期88卷 139-147页

作者： M.Y.Ovando-domínguez M.C.Luján-Hidalgo d.González-Mendoza a.a.vargas-díaz N.Ruiz-Lau F.A.Gutiérrez-Miceli C.A.Lecona-Guzmán Laboratorio de Cultivo de Tejidos Vegetales.Tecnológico Nacional de México/Instituto Tecnológico de Tuxtla Gutiérrez Carretera Panamericana Km.1080.Tuxtla GutiérrezChiapasC.P.29050México Instituto de Ciencias Agrícolas de la Universidad Autónoma de Baja California(ICA-UABC).Carretera a delta s/n C.P.21705 Ejido Nuevo LeónBaja CaliforniaMéxico CONACYT-Colegio de Postgraduados Campus CampecheCarretera Federal Haltunchén-Edzna km 17.5.SihochacChampotónCampecheCP 24450México CONACYT-Tecnológico Nacional de México/Instituto Tecnológico de Tuxtla Gutiérrez.Carretera Panamericana Km.1080.Tuxtla Gutiérrez ChiapasC.P.03940México

Callus cultures of Annona muricata and Annona purpurea were induced in Murashige and Skoog(MS)medium supplemented with different concentrations of 1-naphthylacetic acid(NAA),6-benzyladenine(BA)and 2,4-dichlorophenoxyacetic acid(2,4-d)utilized hypocotyls with *** highest percentage of callus formation was the treatment supplemented with 3 mg L-1 NAA for ***(100%)while for *** in lower percentage(75%).BA stimulated the formation of shoots in all the evaluated concentrations,being the concentration of 2 mg L-1 the one that induced the greater formation of shoots for ***(23 shoots/explant)and ***(28 shoots/explant).The content of total phenols,flavonoids and antioxidant activity was measured in the callus obtained from both *** results showed that a higher content of total phenols was quantified in callus of ***(27.8 mg g-1 dw)compared to ***(23.2 mg g-1 dw).The highest content of total flavonoids was observed in the callus of ***(8.0μg g-1 dw).Antioxidant activity was determined by the 2,2-diphenyl-1-picrylhydracil radical *** concentration required for 50%inhibition(IC50)of the 2,2-diphenyl-1-picrylhydracil radicals were 4.22μg mL-1 in methanolic extracts of callus of ***,while in extracts of callus of *** was 2.86μg mL-1,in both cases was greater than that found for *** culture of the species studied in this work represents an alternative for the production of natural antioxidants.

关键词： Annonaceae antioxidant activity 6-benzyladenine secondary metabolites tissue culture

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Sustained volume decreases in simple renal cysts after sclerotherapy using NBCA with or without hydrodissection

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Journal of Interventional Medicine 2021年第1期4卷 15-20页

作者： Mario I.Cardenas-vargas Mario I.Ortiz Jeannett Izquierdo-Veg Mariana díaz-Zamudio Radiology department Hospital General de PachucaPachucaHidalgoMexico Academic Area of Medicine.Universidad Autonoma del Estado de Hidalgo.Pachuca HidalgoCP 42160Mexico Radiology department Unidad de Patología ClínicaGuadalajaraJaliscoMexico

The present study aimed to determine the effectiveness of sclerotherapy using NBCA(Histoacryl Blue(?);***,Melgungen,Germany),with or without hydrodissection,for the treatment of simple renal *** and Methods:Patients who presented to an interventional radiology clinic for the diagnosis of symptomatic renal cysts which had previously been identified at an outpatient clinic were selected for inclusion in this study.A total of 28 patients were randomly divided into 2 groups,based on whether or not they underwent hydrodissection along with ultrasound-guided NBCA-based *** were performed at 0,7,and 180 days postprocedure to record the residual volume of the renal cysts and to determine the efficacy of the ***:A total of 32 cysts in 28 patients were treated with sclerotherapy,18(64%) females and 10(36%) *** average age of the patients was 61.8 years(range:33-89 years).All patients reported an improvement in symptoms associated with the existing renal cysts at 7 and 180 days post-procedure,and at 7 days post-procedure a statistically significant reduction in cyst volume was observed(all patients:96.8%;group A:96%;group B:97.6%).The reduced cyst volume was still observed 180 days post-procedure(all patients:98.6%;group A:98.2%;group B:98.9%).There was no significant difference between the two treatment ***: There is a significant and persistent reduction in the volume of renal cysts,in addition to an improvement of the associated symptoms,after treatment with NBCA-based sclerotherapy,with or without hydrodissection.

关键词： Renal cyst N-butyl-2-cyanoacrylate Sclerotherapy Hydrodissection

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Urban Plant Biomass Residues from the Neotropics and Their Potential for Thermal Energy Generation

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Journal of Renewable Materials 2023年第9期11卷 3547-3566页

作者： John Freddy Gelves díaz Ludovic dorkis Richard Monroy-Sepúlveda Sandra Rozo-Rincón Gabriel de Jesús Camargo vargas Competitiveness and Sustainability for development Research Group Faculty of EngineeringUniversidad Libre-Cúcuta SectionalCúcutaColombia Catalysis and Nanomaterials Research Group Faculty of MinesUniversidad Nacional de Colombia-Medellín SectionalMedellínColombia detecal Research Group Faculty of EngineeringUniversidad Libre-BogotáSectionalBogotáColombia

The material associated with tree pruning in a city in the Colombian neotropics was characterized in order to determine its energy *** species studied for their relevance in the territory were Prosopis juliflora,Licania tomentosa,Terminalia catappa,azadirachta indica,Pithecellobium dulce,Ficus benjamina and Leucaena *** content,bulk density,hygroscopic response,elemental chemical analysis,proximal analysis,calorific value,ease of ignition and combustion,thermogravimetric and heat flow analysis,steam generation capacity,and qualitative analysis of gases(mass spectrometry)were *** results that were obtained show high initial moisture contents that vary between 37%and 67%and a variable density(when dry)between 0.21 and 0.41 g/***,it was shown that all residues have lower carbon and sulfur content compared to a reference mineral ***,the residues of some species have higher nitrogen contents compared to the same *** biomasses are characterized by their high content of volatile fractions and by having a lower content of inorganic matter compared to *** lower calorific values of these residues are between 14170 and 16928 kJ/kg,which are not negligible compared to other *** characteristic would be related to the high presence of hemicellulose in the *** gas monitoring revealed that there are different airflow needs in order to ensure complete *** generation tests showed that the calorific value should not be the most relevant criterion to establish the potential use of the waste,since leucaena leucocephala,despite having the highest calorific value,was the material with the lowest performance in steam generation.

关键词： Calorific value characterization combustion combustible material urban flora

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Selection and Analysis of Polymorphisms in Somaclonal Variants of Agave 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-Guzmán Federico Antonio Gutiérrez-Miceli Víctor Manuel Ruiz-Valdiviezo Arely Anayansi vargas-díaz Laboratorio de Biotecnología Vegetal Instituto Tecnológico de Tuxtla GutiérrezTecnológico Nacional de MéxicoTuxtla GutiérrezChiapas29050México CONACYT-Colegio de Postgraduados Campus Campeche ChampotónCampeche24450México

Agave 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 high concentrations(30–60 mM).Only the callus exposed to 15 mM EMS presented shoot formation;the exposure time of two hours produced the largest quantity of shoots regenerated per callus(21 shoots/callus).In order to generate somaclonal variants resistant to Fusarium oxysporum,a selection pressure was applied through 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 generating shoots(3.5 shoots/callus).Molecular markers type RAPd,ISSR and dAMd were used to evaluate the genetic 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 groups was:0.28(dAMd),0.09(ISSR)and 0.14(RAPd).dAMd revealed a greater percentage of polymorphism than RAPd and *** bands were detected in the somaclonal *** indicated that the EMS caused genetic variation in the regenerated plants conferring resistance to them against Fusarium oxysporum.

关键词： Mutagenesis polymorphisms genetic variation molecular markers

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Biodiversity-friendly Agricultural Practices in the Indigenous Agricultural Systems in the Biodiversity Corridor of the Alto Paraná Atlantic Forest (Paraguay)

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Research in Ecology 2021年第3期3卷 1-7页

作者： Federico vargas Lehner Ruth Tiffer-Sotomayor Alejandrino díaz Alberto Yanosky Faculty of Agricultural Sciences Universidad Nacional de AsunciónParaguay Environment Natural Resources&Blue EconomyWorld BankWashingtonD.C.United States ItaipúBinacional AsunciónParaguay Guyra Paraguay/CONACYT Carlos BovedaViñas CueAsunciónParaguay

Agricultural systems result of the coevolution between social and natural systems,where biodiversity and natural resources play an important role,emerging interactions between crops and the natural environment that allow the development of ecological processes which interact with external *** research aims to describe the agricultural practices developed by the Guarani Indigenous people in the agricultural systems located within the biodiversity corridor of the Upper Parana Atlantic *** exploratory study is focused on multiple cases,with a qualitative approach and from data collected during 2017 and 2018 in eleven indigenous *** main practices developed for the management of biodiversity are polyculture,rotation,and embroideries;they also practice agroforestry and *** main difficulty they face is the reduction of the surrounding biodiversity,which affects the sustainability of the *** study shows ways for nature-based solutions and ecosystem-based adaptation according to current needs for greening the economy.

关键词： Indigenous agriculture Agrobiodiversity Slash-and-burn Nature based solutions Ecosystem based adaptation

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Optimal Positioning Strategy for Multi-Camera Zooming drones

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IEEE/CAA Journal of Automatica Sinica 2024年第8期11卷 1802-1818页

作者： Manuel vargas Carlos Vivas Teodoro Alamo department of System Engineering and Automation University of SevilleSeville 41092Spain

In the context of multiple-target tracking and surveillance applications,this paper investigates the challenge of determining the optimal positioning of a single autonomous aerial vehicle or agent equipped with multiple independently-steerable zooming cameras to effectively monitor a set of targets of *** camera is dedicated to tracking a specific target or cluster of *** key innovation of this study,in comparison to existing approaches,lies in incorporating the zooming factor for the onboard cameras into the optimization *** enhancement offers greater flexibility during mission execution by allowing the autonomous agent to adjust the focal lengths of the onboard cameras,in exchange for varying real-world distances to the corresponding targets,thereby providing additional degrees of freedom to the optimization *** proposed optimization framework aims to strike a balance among various factors,including distance to the targets,verticality of viewpoints,and the required focal length for each *** primary focus of this paper is to establish the theoretical groundwork for addressing the non-convex nature of the optimization problem arising from these *** this end,we develop an original convex approximation *** paper also includes simulations of diverse scenarios,featuring varying numbers of onboard tracking cameras and target motion profiles,to validate the effectiveness of the proposed approach.

关键词： Convex optimization projective transformation unmanned aerial vehicle visual object tracking visual surveillance.

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Prevalence of type 2 diabetes mellitus in the pediatric population of a third-level care hospital in Mexico City in 2013 and 2018

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World Journal of diabetes 2023年第3期14卷 290-298页

作者： Jorge Mario Molina-díaz Blanca Estela vargas-Terrez Patricia Guadalupe Medina-Bravo Antonia Martínez-Ambrosio América Liliana Miranda-Lora Miguel Klünder-Klünder department of Child Endocrinology Children’s Hospital Federico GomezAutonomous University of MexicoMexico City 06250Mexico Faculty of Business La Salle UniversityMexico City 06250Mexico department of Endocrinology Children’s Hospital Federico GomezMexico City 06720Mexico department of Nursing and Endocrinology Children’s Hospital Federico GómezMexico City 06720Mexico Epidemiological Research Unit in Endocrinology and Nutrition Children’s Hospital Federico GomezMexico City 06720Mexico division of Research Children’s Hospital Federico GomezMexico City 06720Mexico

BACKGROUNd diabetes mellitus type 2(T2dM)is a state of hyperglycemia due to a defect in the secretion and/or action of insulin,and it represents the most common form of diabetes *** Mexico,10.3%of the adult population have been diagnosed with T2dM and it is expanding to the pediatric *** To evaluate and compare the prevalence of T2dM in the pediatric population at the Children’s Hospital,“Hospital Infantil de México Federico Gómez(HIMFG)”,at two time periods:2013 vs *** A comparison of two cross-sectional studies was done(2013 and 2018).The study population was comprised of children and adolescents 8-17 years old,from the diabetes Clinic at the aforementioned institution.A comprehensive interrogation regarding family history and perinatal antecedents was *** blood work after 12 h of fasting was obtained to determine serum levels of glucose,glycated hemoglobin,lipid profile,C-peptide,and *** data were analysed using the statistical software package SPSS v.23.0.A P value ofdered statistically *** A total of 151 patients were included:47 from 2013,and 104 from *** were age differences noted between the two periods with younger patients presenting T2dM in ***,T2dM predominated in the male sex in 55.36%in 2013 vs 32.7%in *** increased prevalence of T2dM was noted from 2013 to 2018(20.2%vs 33.0%,respectively),which was a statistically significant 12.8%increase(Pd adverse lipid *** The prevalence of T2dM at the HIMFG institution from 2013 to 2018 increased by 12.8%(20.2%vs 33.0%,respectively).The study results demonstrate the need for vigilance in T2dM trends,and to strengthen programs of healthy nutrition and physical activity as well as early detection and risk factors for obesity,data on insulin resistance,and metabo

关键词： diabetes Children adolescents Epidemiology Etiology Risk factors and complications

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Effect of Multipoint Heterogeneity on Nonlinear Transformations for Geological Modeling: Porosity-Permeability Relations Revisited

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Journal of China University of Geosciences 2008年第1期19卷 85-92页

作者： J A vargas-Guzmán Saudi Aramco Dhahran 31311 KSA

An analysis of statistical expected values for transformations is performed in this study to quantify the effect of heterogeneity on spatial geological modeling and evaluations. Algebraic transformations are frequently applied to data from logging to allow for the modeling of geological properties. Transformations may be powers, products, and exponential operations which are commonly used in well-known relations （e.g., porosity-permeability transforms）. The results of this study show that correct computations must account for residual transformation terms which arise due to lack of independence among heterogeneous geological properties. In the case of an exponential porosity-permeability transform, the values may be positive. This proves that a simple exponential model back-transformed from linear regression underestimates permeability. In the case of transformations involving two or more properties, residual terms may represent the contribution of heterogeneous components which occur when properties vary together, regardless of a pair-wise linear independence. A consequence of power- and product-transform models is that regression equations within those transformations need corrections via residual cumulants. A generalization of this result is that transformations of multivariate spatial attributes require multiple-point random variable relations. This analysis provides practical solutions leading to a methodology for nonlinear modeling using correct back transformations in geology.

关键词： reservoir static model intrinsic permeability non-Gaussian nonlinear residual moment cumulant unbiased simulation parameter.

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

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

作者： J.C.díaz-Guillén G.vargas-Gutiérrez E.E.Granda-Gutiérrez J.S.Zamarripa-Pia S.I.Pérez-Aguilar J.Candelas-Ramírez L.lvarez-Contreras Centro de Investigacin en Materiales Avanzados S.C.Miguel de Cervantes 120Complejo Industrial ChihuahuaC.P.31109 ChihuahuaChihuahuaMexico Corporacin Mexicana de Investigacin en Materiales S.A.de C.V.Ciencia y Tecnología No 790Fracc.Saltillo 400C.P.25290 SaltilloCoahuilaMexico Centro de Investigaci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

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Global stability for multi-species Lotka-Volterra cooperative systems： One hyper-connected mutualistic-species

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International Journal of Biomathematics 2015年第3期8卷 215-223页

作者： Cruz vargas-de-Leon Unidad de Medicina Experimental Hospital General de Mexico"dr. Eduardo Liceaga" dF 06726 Mexico

We propose two models of one hyper-connected mutualistic-species described by delay differential equations of Lotka-Volterra type. An hyper-connected model comprises a central species interacting with a number of peripheral species around it, that is to say, one animal species （pollinators or dispersers） that interacts with several plant species （flowering plants or fruit trees）, or several animal species that interact with one plant species. We derive a necessary and sufficient condition for the global asymptotic stability of the unique coexisting steady state of hyper-connected systems by means of novel Lyapunov functionals.

关键词： Lotka Volterra cooperative system discrete delays distributed delays Lyapunov functional global stability.

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