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Convergence Analysis of a Block-by-Block Method for Fractional Differential Equations

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Numerical Mathematics(Theory,Methods and Applications) 2012年第2期5卷 229-241页

作者： Jianfei Huang Yifa Tang luis vázquez LSEC ICMSECAcademy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing 100190China Departamento deMatemática Aplicada Facultad de InformáticaInstituto deMatemática Interdisciplinar(IMI)Universidad Complutense de Madrid28040-MadridSpain

The block-by-block method,proposed by Linz for a kind of volterra integral equations with nonsingular kernels,and extended by Kumar and Agrawal to a class of initial value problems of fractional differential equations(FDEs)with Caputo derivatives,is an efficient and stable *** analytically prove and numerically verify that this method is convergent with order at least 3 for any fractional order indexα>0.

关键词： Fractional differential equation Caputo derivative block-by-block method convergence analysis

Early-onset colorectal cancer:A separate subset of colorectal cancer

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World Journal of Gastroenterology 2014年第46期20卷 17288-17296页

作者： Irene osorio Silla Daniel Rueda Yolanda Rodríguez Juan luis García felipe de la Cruz vigo José Perea Department of Surgery 12 de Octubre University HospitalMadrid 28041Spain Molecular Biology Laboratory 12 de Octubre University HospitalMadrid 28041Spain Department of Pathology 12 de Octubre University HospitalMadrid 28041Spain Centre for Cancer Research Medical University of SalamancaSalamanca 37008Spain

Colorectal cancer(CRC)has a great impact on the world *** increasing frequency,CRC is described according to the presenting phenotype,based on its molecular *** of CRC tumors according to their genetic and/or epigenetic alterations is not only important for establishing the molecular bases of the disease,but also for predicting patient outcomes and developing more individualized ***-onset CRC is a heterogeneous disease,with a strong familial component,although the disease is sporadic in an important proportion of *** molecular alterations appear to contribute to the apparent heterogeneity of the early-onset population and subgroups can be distinguished with distinct histopathologic and familial ***,compared with late-onset CRC,there are characteristicsthat suggest that early-onset CRC may have a different molecular *** purpose of this review was to analyze the current state of knowledge about earlyonset CRC with respect to clinicopathologic,familial and molecular ***,these features make it increasingly clear that this subset of CRC may be a separate disease,although it has much in common with late-onset CRC.

关键词： Chromosomal instability CpG island methylator phenotype Early-onset colorectal cancer Lynch syndrome Microsatellite instability

Heterogeneous catalysts with programmable topologies generated by reticulation of organocatalysts into metal-organic frameworks:The case of squaramide

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Nano Research 2021年第2期14卷 458-465页

作者： Anna Broto-Ribas Claudia vignatti Alicia Jimenez-Almarza Javier luis-Barrera Zahra Dolatkhah felipe Gandara Inhar Imaz Ruben Mas-Balleste Jose Aleman Daniel Maspoch Catalan Institute of Nanoscience and Nanotechnology(ICN2) CSIC and The Barcelona Institute of Science and Technology08193 BarcelonaSpain Inorganic Chemistry Department Modulo 7Universidad Autonoma de Madrid28049 MadridSpain organic Chemistry Department Modulo 1Universidad Autonoma de Madrid28049 MadridSpain Materials Science Factory Instituto de Ciencia de Materiales de Madrid(ICMM)Consejo Superior de Investigaciones Cientificas(CSIC)Calle Sor Juana Ines de la Cruz328049 MadridSpain Institute for Advanced Research in Chemical Sciences(IAdChem) Campus Universidad Autonoma de Madrid28049 MadridSpain Institucio Catalana de Recerca i Estudis Avangats(ICREA) 08100 BarcelonaSpain

A well-established strategy to synthesize heterogeneous,metal-organic framework(MoF)catalysts that exhibit nanoconfinement effects,and specific pores with highly-localized catalytic sites,is to use organic linkers containing organocatalytic ***,we report that by combining this linker approach with reticular chemistry,and exploiting three-dimensioanl(3D)MoF-structural data from the Cambridge Structural Database,we have designed four heterogeneous MoF-based catalysts for standard organic *** programmable MoFs are isoreticular versions of pcu IRMoF-16,feu Uio-68 and pillared-pcu SNU-8X,the three most common topologies of MoFs built from the organic linker p.p'-terphenyldicarboxylic acid(tpdc).To synthesize the four squaramide-based MoFs,we designed and synthesized a linker,4,4’-((3,4-dioxocyclobut-1-ene-1,2-diyl)bis(azanedyil))dibenzoic acid(Sq_tpdc),which is identical in directionality and length to tpdc but which contains organocatalytic squaramide *** were chosen because their immobilization into a framework enhances its reactivity and stability while avoiding any self-quenching ***,the four MoFs share the same organocatalytic squaramide moiety,but confine it within distinct pore *** then evaluated these MoFs as heterogeneous H-bonding catalysts in organic transformations:a Friedel-Crafts alkylation and an epoxide *** of them exhibited good performance in both reactions but all showed distinct catalytic profiles that reflect their structural differences.

关键词： reticular chemistry metal-organic frameworks H-bond catalysis squaramide Friedel-Cratts epoxide ring-opening

Promising diagnostic biomarkers of nonalcoholic fatty liver disease and nonalcoholic steatohepatitis: From clinical proteomics to microbiome

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World Journal of Hepatology 2021年第11期13卷 1494-1511页

作者： Carolina Castillo-Castro Alexandro JoséMartagón-Rosado Rocio ortiz-Lopez luis felipe Garrido-Treviño Melissa villegas-Albo Francisco Javier Bosques-Padilla Tecnológico de Monterrey Escuela de Medicina y Ciencias de la SaludMonterrey 64710Mexico Unidad de Investigación de Enfermedades Metabólicas Instituto Nacional de Ciencias Médicas y NutriciónCiudad de México 14080Mexico Centro Regional para el Estudio de las Enfermedades Digestivas Servicio de GastroenterologíaFacultad de Medicina y Hospital Universitario Dr.JoséEleuterio GonzálezUniversidad Autónoma de Nuevo LeónMonterrey 64460Mexico

Fatty liver has been present in the lives of patients and physicians for almost two *** knowledge has been generated regarding its etiology and consequences,although a long path seeking novel and innovative diagnostic biomarkers for nonalcoholic fatty liver disease(NAFLD)and nonalcoholic steatohepatitis(NASH)is still *** the one hand,proteomics and lipidomics have emerged as potential noninvasive resources for NAFLD *** contrast,metabolomics has been able to distinguish between NAFLD and NASH,even detecting degrees of *** the other hand,genetic and epigenetic markers have been useful in monitoring disease progression,eventually functioning as target *** markers involved in immune dysregulation,oxidative stress,and inflammation are involved in the instauration and evolution of the ***,the fascinating gut microbiome is significantly involved in NAFLD and *** review presents state-of-the-art biomarkers related to NAFLD and NASH and new promises that could eventually be positioned as diagnostic resources for this *** is evident,despite great advances in studying these biomarkers,there is still a long path before they translate into clinical benefits.

关键词： Fatty liver Biomarkers Nonalcoholic fatty liver disease Nonalcoholic steatohepatitis

Comparative carbon emission assessments of recycled and natural aggregate concrete: Environmental influence of cement content

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Geoscience Frontiers 2021年第6期12卷 72-81页

作者： Marian Sab?u Dan v.Bompa luis F.o.Silva Department of Civil and Environmental Engineering Universidad de la Costa Department of Civil and Environmental Engineering University of Surrey Departamento de Ingeniería Civil y Arquitectura Universidad de Lima

This work examines the environmental and geochemical impact of recycled aggregate concrete production with properties representative for structural applications. The environmental influence of cement content, aggregate production, transportation, and waste landfilling is analysed by undertaking a life cycle assessment and considering a life cycle inventory largely specific for the region. To obtain a detailed insight into the optimum life cycle parameters, a sensitivity study is carried out in which supplementary cementitious materials, different values of natural-to-recycled aggregate content ratio and case-specific transportation distances were considered. The results show that carbon emissions were between 323 and 332 kg Co2e per cubic metre of cement only natural aggregate concrete. These values can be reduced by up to 17% by replacing 25% of the cement with fly ash. By contrast, carbon emissions can increase when natural coarse aggregates are replaced by recycled aggregates in proportions of 50% and 100%, and transportation is not included in analysis. However, the concrete with 50% recycled aggregate presented lower increase, only 0.3% and 3.4% for normal and high strength concrete, respectively. In some cases, the relative contribution of transportation to the total carbon emissions increased when cement was replaced by fly ash in proportions of 25%, and case-specific transportation distances were considered. In absolute values, the concrete mixes with 100% recycled aggregates and 25% fly ash had lower carbon emissions than concrete with cement and natural aggregates only. Higher environmental benefits can be obtained when the transportation distances of fly ash are relatively short(15–25 km) and the cement replacement by fly ash is equal or higher than 25%, considering that the mechanical properties are adequate for practical application. The observations from this paper show that recycled aggregate concrete with strength characteristics representative for s

关键词： Life cycle assessment Recycled aggregate Natural aggregate Transportation distance openLCA

How does high-intensity intermittent training affect recreational endurance runners? Acute and chronic adaptations: A systematic review

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Journal of Sport and Health Science 2017年第1期6卷 54-67页

作者： felipe García-Pinillos víctor M.Soto-Hermoso Pedro A.Latorre-Román Department of Corporal Expression University of Jaen Department of Sports Sciences University of Granada

objective: This systematic review aimed to critically analyze the literature to determine how high-intensity intermittent training(HIIT) affects recreational endurance runners in the short-and ***: Electronic databases were searched for literature dating from January 2000 to october 2015. The search was conducted using the key words "high-intensity intermittent training" or "high-intensity interval exercise" or "interval running" or "sprint interval training" and "endurance runners" or "long distance runners". A systematic approach was used to evaluate the 783 articles identified for initial review. Studies were included if they investigated HIIT in recreational endurance runners. The methodological quality of the studies was evaluated using the Physiotherapy Evidence Database(PEDro) scale(for intervention studies) and the modified Downs and Black Quality Index(for cross-sectional studies).Results: Twenty-three studies met the inclusionary criteria for review. The results are presented in 2 parts: cross-sectional(n = 15) and intervention studies(n = 8). In the 15 cross-sectional studies selected, endurance runners performed at least 1 HIIT protocol, and the acute impact on physiological, neuromuscular, metabolic and/or biomechanical variables was assessed. Intervention studies lasted a minimum of 4 weeks, with 10 weeks being the longest intervention period, and included 2 to 4 HIIT sessions per week. Most of these studies combined HIIT sessions with continuous run(CR) sessions; 2 studies' subjects performed HIIT ***: HIIT-based running plans(2 to 3 HIIT sessions per week, combining HIIT and CR runs) show athletic performance improvements in endurance runners by improving maximal oxygen uptake and running economy along with muscular and metabolic adaptations. To maximize the adaptations to training, both HIIT and CR must be part of training programs for endurance runners.

关键词： Endurance High-intensity training Intermittent exercises Interval running Long-distance runners Running

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An interactive tool for visualization and prediction of solar radiation and photovoltaic generation in Colombia

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Big Earth Data 2023年第3期7卷 904-929页

作者： Gabriel Narvaez luis felipe Giraldo Michael Bressan Camilo A.Guillen María A.Pabón Nicolás Díaz Manuel felipe Porras Brayan Herney Medina Fernando Jiménez Guillermo Jiménez-Estévez Andres Pantoja Corinne Alonso Department of Electrical and Electronic Engineering Universidad de Los AndesBogotáColombia Laboratory for Analysis and Architecture of Systems ToulouseFrance Department of BiomedicalEngineering Universidad de Los AndesBogotáColombia Department of Systems Engineering Corporacion Universitaria del HuilaNeivaColombia Department of Electronic Engineering Universidad deNariñoPastoColombia

This paper presents the building process of an interactive instrument called the Colombian Solar Atlas able to easily visualize meteorological data but also assess the current and future potentials of solar photovoltaic generation throughout the whole territory of Colombia,South *** new tool is based on two different meteorological *** first one is done with historical data extracted from satellite imagery information,and the other one corresponds to data issues from regional-scale climate change projection *** satellite database was validated with different in-situ *** Colombian Solar Atlas uses basic and advanced photovoltaic generation models to estimate the generation of a custom solar *** this tool,a user selects a point on the map and can have directly pertinent information to search for an optimal location with a spatial resolution of 4 *** tool is the first open interactive online tool particularly adapted to study the photovoltaic power potential in Colombia,considering the country’s needs and native language.

关键词： Solar atlas Pv power potential climate change Colombia data validation

Thermodynamic analysis, synthesis, characterization, and evaluation of 1-ethyl-3-methylimidazolium chloride: Study of its effect on pretreated rice husk

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Chinese Journal of Chemical Engineering 2023年第8期60卷 143-154页

作者： Eileen Katherine Coronado-Aldana Cindy Lizeth ferreira-Salazar Nubia Yineth Piñeros-Castro Rubén vázquez-Medina felipe A.Perdomo Universidad de BogotáJorge Tadeo Lozano Facultad de Ciencias Naturales e IngenieríaCra.422-61CundinamarcaBogotáColombia Instituto Politecnico Nacional CICATA QueretaroCerro Blanco 141Colinas del Cimatario76090 QueretaroMexico School of Engineering University of EdinburghEdinburgh EH93FBUnited Kingdom

This work is focused on the determination of the optimal reaction conditions to synthesize the ionic liquid 1-ethyl-3-methylimidazolium chloride([EMIM][Cl]) and assess its suitability for the pretreatment of rice husk. The modified UNIFAC(UNIversal quasi-chemical Functional-group Activity Coefficients)approach for ionic liquids is used to develop a thermodynamic model that describes the reactive system methylimidazole(MIM), chloroethane(C_(2)H_(5)Cl) and [EMIM][Cl]. The model allows to study the phase equilibria coexistence(vapor–liquid equilibria and solid–liquid equilibria) and yields the theoretically optimal conditions to synthesize the ionic liquid. The model predictions are validated with the available experimental and reported data. By implementing the developed model, a simple way to synthesize ionic liquid [EMIM][Cl] was found allowing to study its influence on the structure and morphology of pretreated rice husk. The lignocellulosic materials involved in this study are characterized by their composition, enzymatic digestibility, scanning electron microscopy, and crystallinity. Compared to untreated material, [EMIM][Cl]-pretreated rice husk produces cellulose that can be efficiently enzymatic hydrolyzed with high sugar yields. This work offers a suitable methodology to include the synthesis and thermodynamics of the solvent media within the design of low-cost ionic liquids for lignocellulosic biomass pretreatment.

关键词： Ionic liquids Fluid-phase equilibria Thermodynamics Waste treatment UNIFAC approach

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Kinetic analysis via mathematical modeling for ferrous iron oxidation in a class of SBR-type system

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Chinese Journal of Chemical Engineering 2019年第10期27卷 2472-2480页

作者： Edgar NTec-Caamal Refugio Rodríguez-vázquez luis GTorres-Bustillos Ricardo Aguilar-López Center for Research and Advanced Studies of the National Polytechnic Institute Av.Instituto Politécnico Nacional No.2508Colonia San Pedro ZacatencoC.P.07360 Ciudad de México D.F.Mexico Interdisciplinary Professional Unit of Biotechnology-National Polytechnic Institute(UPIBI-IPN) Acueducto s/nLa Laguna TicománGustavo A.Madero07340Ciudad de MéxicoMexico

This paper analyses the oxidation of ferrous iron via chemical and biological means in a class of Sequential Batch Reactors(SBR-type).For this,a kinetic model for the study of iron oxidation system is proposed,followed by a parametric sensitivity analysis and a bifurcation analysis,which allow selecting the most influential kinetic parameters in order to ensure a suitable prediction capacity of the mathematical *** system consists of two SBR bioreactors,the first being used to produce hydrogen peroxide(H2o2)that is fed to a second reactor where the iron oxidation is carried out by chemical–biological *** predictions were compared with experimental data for the production of H2o2 and for ferrous iron oxidation,finding suitable correlation coefficients(r2 N 0.98)for each state *** bifurcation analysis showed the trajectories of the main variables,such as,biomass,H2o2 and ferrous iron,under the change of the most influential kinetic *** analysis demonstrates the usefulness of the constructed model to predict the kinetic behaviour of the SBR-type process.

关键词： Bifurcation analysis Hydrogen peroxide Iron oxidation Modeling Simulation

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