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The ρ-variation of the Hermitian Riesz Transform

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Acta Mathematica Sinica,English Series 2010年第10期26卷 1827-1838页

作者： raquel CRESCIMBENI Francisco Javier MARTíN-reyes alberto DE lA TORRE José l.TORREA Departamento de Matemática Universidad Nacional del Comahue Facultad de Economía y Administración Departamento de Análisis Matemático Facultad de Ciencias Universidad de Málaga Facultad de Ciencias Universidad Autónoma de Madrid ICMAT-CSIC-UAM-UCM-UC3M

In this paper we prove the behaviour in weighted lp spaces of the oscillation and variation of the Hilbert transform and the Riesz transform associated with the Hermite operator of dimension 1. We prove that this operator maps lP（R, w（x）dx） into itself when w is a weight in the Ap class for 1 〈 p 〈 ∞. For p = 1 we get weak type for the A1 class. Weighted estimated are also obtained in the extreme case p = ∞.

关键词： Oscillation-p-variation-singular integral-Hermite operator

Use of recycled concrete aggregates in asphalt mixtures for pavements:A review

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Journal of Traffic and Transportation Engineering(English Edition) 2022年第5期9卷 725-741页

作者： Juan Gabriel Bastidas-Martínez Fredy alberto reyes-lizcano Hugo Alexander Rondón-Quintana Faculty of Engineering Universidad Piloto de ColombiaBogotáDC 110231Colombia Faculty of Engineering Pontificia Universidad JaverianaBogotáDC 110131Colombia Facultad del Medio Ambiente y Recursos Naturales Universidad Distrital Francisco Joséde CaldasBogotáDC 110131Colombia

large quantities of natural aggregates(NA)are required in the manufacturing of asphalt mixtures for *** extraction of NA generates high environmental impacts that negatively affect environmental preservation and *** alternative materials obtained in construction and demolition processes in civil construction worked have been studies as possible replacements for NA,with the purpose of reducing these environmental *** foregoing study presents a state of knowledge review referring to the use of recycled concrete aggregates(RCA)when these are used in the manufacturing of asphalt mixtures(mainly hot-mix asphalt HMA type).Environmental aspects are presented,as well as possible benefits and limitations of using RCA as replacements for NA in asphalt ***,it is not possible to establish a behavior pattern,since the characteristics of the RCA are very heterogeneous and vary from the original source of the *** is highlighted from the literature that RCA has a wide potential for use in the manufacture of asphalt mixtures,since in most studies,the mixtures with these materials comply the quality requirements contemplated by the construction specifications,mainly in low-volume ***,based on the literature review,some recommendations and suggestions are presented for future research.

关键词： Recycled concrete aggregates Asphalt mixtures Mechanical properties Volumetric composition

Increased DNA binding activity of NF-κB,STAT-3,SMAD3 and AP-1 in acutely damaged liver

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World Journal of Gastroenterology 2006年第37期12卷 5995-6001页

作者： Adriana Salazar-Montes luis Ruiz-Corro Ana Sandoval-Rodriguez alberto lopez-reyes Juan Armendariz-Borunda Institute of Molecular Biology in Medicine and Gene Therapy CUCS University of Guadalajara Apdo. Postal 2-123 Guadalajara 44281 Jal Mexico Institute of Molecular Biology in Medicine and Gene Therapy CUCS University of Guadalajara Apdo.Postal 2-123 Guadalajara 44281 Jal Mexico OPD Hospital Civil de Guadalajara Guadalajara Jal Mexico

AIM: To investigate the role of genes and kinetics of specific transcription factors in liver regeneration, and to analyze the gene expression and the activity of some molecules crucially involved in hepatic regeneration. METHODS: USING gel-shift assay and RT-PCR, transcription factors, such as NF-κB, STAT-3, SMAD3 and AP-1, and gene expression of inducible nitric oxide synthase (iNOS), hepatocyte growth factor (HGF) and c-met were analyzed in an animal model of chemically induced hepatectomy. RESUlTS: Gene expression of HGF and its receptor c-met peaked at 3 h and 24 h after acute CCl4 intoxi- cation. iNOS expression was only observed from 6 to 48 h. Transcriptional factor NF-κB had an early activation at 30 min after acute liver damage. STAT-3 peaked 3 h post- intoxication, while AP-1 displayed a peak of activation at 48 h. SMAD3 showed a high activity at all analyzed times. CONClUSION: TNF-α and Il-6 play a central role in hepatic regeneration. These two molecules are responsible for triggering the cascade of events and switch-on of genes involved in cell proliferation, such as growth factors, kinases and cyclins which are direct participants of cell proliferation.

关键词： Hepatic regeneration Transcription factor Gene regulation

Analysis and parameter extraction of memristive structures based on Strukov's non-linear model

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Journal of Semiconductors 2018年第12期39卷 106-113页

作者： A.Avila Garcia l.Ortega reyes Centro de Investigacion y de Estudios Avanzados del Instituto Polit6cnico Nacional Departamento de Ingenieria ElectricaSeccion de Electronica del Estado SolidoMexico 07360Mexico

Diverse models have been proposed for explaining the electrical performance of memristive devices. In principle, the behavior of internal variables associated to each one could be extracted from experimental results. In a former work, thermally grown TiOmemristive structures were built and characterized to obtain the constitutive relationship(magnetic flux versus charge). The aim of this work is to continue that analysis by determining the microscopic parameters within the frame of a simple model. We use the already obtained memristance dependence of time and the basic expressions from the non-linear model proposed by Strukov et al. to compute the state-variable,the mobility of the doping species, the speed of the boundary between the doped and the undoped regions, the voltages and the electric fields on the distinct regions. The power dissipation and its time evolution are also presented. Moreover, a quite different window function from those formerly proposed, which was estimated from experimental data, is also determined. This information provides a straightforward picture of the ionic transport during one cycle of a square voltage waveform within the framework of this simple model. Finally, a quality factor is proposed as the key parameter for actual memristors viewed under the same model.

关键词： memristors parameter extraction non-linear model experimental window function

Context-dependent insect predation pressure on an avian ectoparasite

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Insect Science 2023年第6期30卷 1784-1797页

作者： Angela Salido Jesús Veiga Joaquín luis reyes-lópez Francisco Valera Department of Botany Ecology and Plant PhysiologyUniversity of CórdobaCórdobaSpain Departamento de Ecología Funcional y Evolutiva Estación Experimental de ZonasÁridas(EEZA-CSIC)AlmeríaSpain Department of Parasitology University of GranadaGranadaSpain MEMEG Department of BiologyLund UniversityLundSweden

Context dependence arises when ecological relationships vary with the conditions under which they are observed. Context dependence of interactions involving parasites is poorly known, even if it is key to understanding host–parasite relationships and food web dynamics. This paper investigates to which extent predation pressure on an avian ectoparasite (Carnus hemapterus) is context-dependent. Based on a predator-exclusion experiment, predation pressure on C. hemapterus pupae in the host's nest for 3 years, and its variation between habitat types are quantified. Variation in precipitation and normalized difference vegetation index (NDVI) is also explored as a likely cause of context dependency. We hypothesize that predation pressure should fluctuate with such surrogates of food availability, so that inter-annual and intra-annual differences may emerge. The number of nests with significant reduction of pupae varied widely among years ranging from 24% to 75%. However, average pupae reduction in nests where a significant reduction occurred did not vary between years. No differences in predation rates between habitat types were detected. Precipitation and NDVI varied widely between years and NDVI was consistently lower around nests on cliffs than around nests on trees and farmhouses. Parallels were found between variation in predation pressure and precipitation/NDVI at a wide scale (highest predation the driest year, and much lower the 2 rainier ones), but not at the nest scale. This paper shows clear context-dependent insect predation pressure on an ectoparasite under natural conditions, and that such interaction changes in signs rather than magnitude between years. The causes for these variations require longer-term studies and/or well-designed, large-scale experiments.

关键词： ants arid areas Carnus hemapterus consumer-resource interaction ecosys-tem productivity predator-parasite rainfall

Characterization of Cd1-xZnxTe（0≤x≤1） Nanolayers Grown by Atomic layer Deposition on GaSb and GaAs（001） Oriented Substrates

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Journal of Electronic Science and Technology 2019年第2期17卷 97-108页

作者： Joel Díaz-reyes Roberto Saúl Castillo-Ojeda José Eladio Flores-Mena Center for Research in Applied Biotechnology Instituto Politécnico Nacional Tepetitla 90700 Mexico Universidad Politécnica de Pachuca Pachuca 43830 Mexico Faculty of Sciences of the Electronics Autonomous University of Puebla Puebla 72570 Mexico

ZnTe, CdTe, and the ternary alloy CdZnTe are important semiconductor materials used widely for the detection of an important range of electromagnetic radiation as gamma ray and X-ray. Although, recently these materials have acquired renewed importance due to the new explored nanolayer properties of modern devices. In addition, as shown in this work they can be grown using uncomplicated synthesis techniques based on the deposition in vapour phase of the elemental precursors. This work presents the results obtained from the deposition of nanolayers of these materials using the precursor vapour on GaAs and GaSb (001) substrates. This growth technique, extensively known as atomic layer deposition (AlD), allows the layers growth with nanometric dimension. The main results presented in this work are the used growth parameters and the results of the structural characterization of the layers by the means of raman spectroscopy measurements. raman scattering shows the peak corresponding to longitudinal optical (lO)-ZnTe, which is weak and slightly redshift in comparison with that reported for the ZnTe bulk at 210 cm^-1. For the case of the CdTe nanolayer, raman spectra presented the lO-CdTe peak, which is indicative of the successful growth of the layer. Its weak and slightly redshift in comparison with that reported for the CdTe bulk can be related with the nanometric characteristic of this layer. The performed high-resolution X-ray diffraction (HR-XRD) measurement allows to study some important characteristics such as the crystallinity of the grown layer. In addition, the HR-XRD measurement suggests that the crystalline quality has dependence on the growth temperature.

关键词： Ⅲ-Ⅴ substrates atomic layer deposition(AlD) defect generation mechanism ternary alloy Cd1-xZnxTe Zn and Cd mixture

Electrochemical and spectroscopic study of interfacial interactions between chalcopyrite and typical flotation process reagents

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International Journal of Minerals,Metallurgy and Materials 2016年第2期23卷 127-136页

作者： Gustavo Urbano Isabel lázaro Israel Rodríguez Juan luis reyes Roxana larios Roel Cruz Instituto de Metalurgia Universidad Autonotrla de San Luis PotosiAvSierra Leona 550Lomas 2a SeccionSan Luis PotosiS.L.P.78210Mexico Industrial Minera Mexico S.A.de C.V. San Luis PotosiS.L.P.Mexico Centro Universitario de Ciencias Exactas e Ingenierias Universidad de GuadalajaraGuadalajaraJaliscoMexico

Comparative voltammetry and differential double-layer capacitance studies were performed to evaluate interfacial interactions between cnalcopyrite（CuFeS2） and n-isopropyl xanthate（X） in the presence of ammonium bisulfite/39wt%SO2 and caustic starch at different pH *** spectroscopy,Fourier transform infrared（FTIR） spectroscopy,contact angle measurements,and microflotation tests were used to establish the type and extent of xanthate adsorption as well as the species involved under different mineral surface conditions in this *** results demonstrate that the species that favor a greater hydrophobicity of chalcopyrite are primarily CuX and S^0,whereas oxides and hydroxides of Cu and Fe as well as an excess of starch decrease the hydrophobicity.A conditioning of the mineral surface with ammonium bisulfite/39wt%SO2 at pH 6 promotes the activation of surface and enhances the xanthate ***,this effect is diminished at pH ≥ 8,when an excess of starch is added during the preconditioning step.

关键词： sulfide minerals chalcopyrite xanthates flotation interfacial reactions electrochemistry spectroscopy

A novel motion tracking system for evaluation of functional rehabilitation of the upper limbs

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Neural Regeneration Research 2013年第19期8卷 1773-1782页

作者： ngel Gil-Agudo Ana de los reyes-Guzmán Iris Dimbwadyo-Terrer Benito Peasco-Martín alberto Bernal-Sahún Patricia lópez-Monteagudo Antonio del Ama-Espinosa José luis Pons Department of Biomechanics and Technical Aids National Hospital for Spinal Cord Injury Health Department Indra SystemsAlcobendas Madrid Spain Bioengineering Group Spanish National Research Council (CSIC) Arganda del ReyMadrid Spain

Upper limb function impairment is one of the most common sequelae of central nervous system in jury, especially in stroke patients and when spinal cord injury produces tetraplegia. Conventional assessment methods cannot provide objective evaluation of patient performance and the effec tiveness of therapies. The most common assessment tools are based on rating scales, which are inefficient when measuring small changes and can yield subjective bias. In this study, we designed an inertial sensorbased monitoring system composed of five sensors to measure and analyze the complex movements of the upper limbs, which are common in activities of daily living. We devel oped a kinematic model with nine degrees of freedom to analyze upper limb and head movements in three dimensions. This system was then validated using a commercial optoelectronic system. These findings suggest that an inertial sensorbased motion tracking system can be used in patients who have upper limb impairment through data integration with a virtual realitybased neurorehabili tation system.

关键词： neural regenerationtion tracking upperroregenerationbrain injury spinal cordmb: neurorehabilitationnjury kinematic analysis inertial measurement mo-virtual reality sensors grants-supported paper neu-

The Many Faces of Plant SWI/SNF Complex

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Molecular Plant 2014年第3期7卷 454-458页

作者： Jose C. reyes Molecular Biology Department Centro Andaluz de Biologia Molecular y Medicina Regenerativa (CABIMER) Consejo Superior de Investigaciones Cientificas (CSIC) Av. Americo Vespucio 41092 Seville Spain

THE SWI/SNF COMPlEXESIn plants, as well as in metazoans, the execution of devel- opmental programs and the response to environmental stimuli depend on changes in gene transcription programs that require extensive chromatin modifications of basically two types： posttranslational modification of histones and ATP-dependent reorganization of histones-DNA interac- tions. Many different nuclear machineries are necessary to carry out chromatin modifications at the appropriate time and place.

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