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The Effectiveness of the Havriliak-Negami Model in Predicting the Master Curves of the Asphalt Blends with SBS Triblock Copolymer and Organic-Montmorillonite at Different Temperatures and Frequencies

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Journal of Materials Science and Chemical Engineering 2024年第7期12卷 23-39页

作者： María Ángeles vargas-Hernández Miguel Ángel vargas pedro R. García-Morán Humberto vázquez-Torres Divisin de Ingeniera Qumica y Bioqumica TecNMTecnolgico de Estudios Superiores de Ecatepec Edo. de Mxico Mxico Facultad de Qumica Universidad Nacional Autonma de Mxico Cd. de Mxico Mxico Facultad de Ciencias Bsicas Ingeniera y Tecnologa Universidad Autnoma de Tlaxcala Tlaxcala Mxico Departamento de Fsica Universidad Autnoma Metropolitana-Iztapalapa Cd. de Mxico Mxico

The dynamic viscoelastic properties of asphalt AC-20 and its composites with Organic-Montmorillonite clay (OMMt) and SBS were modeled using the empirical Havriliak-Negami (HN) model, based on linear viscoelastic theory (LvE). The HN parameters, α, β, G0, G∞and τHN were determined by solving the HN equation across various temperatures and frequencies. The HN model successfully predicted the rheological behavior of the asphalt and its blends within the temperature range of 25˚C - 40˚C. However, deviations occurred between 40˚C - 75˚C, where the glass transition temperature Tg of the asphalt components and the SBS polymer are located, rendering the HN model ineffective for predicting the dynamic viscoelastic properties of composites containing OMMt under these conditions. Yet, the prediction error of the HN model dropped to 2.28% - 2.81% for asphalt and its mixtures at 100˚C, a temperature exceeding the Tg values of both polymer and asphalt, where the mixtures exhibited a liquid-like behavior. The exponent α and the relaxation time increased with temperature across all systems. Incorporating OMMt clay into the asphalt blends significantly enhanced the relaxation dynamics of the resulting composites.

关键词： Asphalt Blends Master Curve Linear viscoelasticity Havriliak-Negami Model

Inversion of walkaway vSP data in the presence of lateral velocity heterogeneity

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Energy Geoscience

Energy Geoscience 2024年第2期5卷 304-313页

作者： vladimir Grechka Ilya Tsvankin pedro Contreras CWP Department of GeophysicsColorado School of MinesGoldenCO80401USA PDvSA-INTEvEP Apartado 76343Caracas1070AVenezuela Borehole Seismic LLC USA Department of Physics ULAVenezuela

Multi-azimuth walkaway vertical seismic profiling is an established technique for the estimation of in situ slowness surfaces and inferring anisotropy ***,this technique requires the assumption of lateral homogeneity,which makes the horizontal slowness components at depths of downhole receivers equal to those measured at the *** violations of this assumption,such as lateral heterogeneity or nonzero dip of intermediate interfaces,lead to distortions in reconstructed slowness surfaces and,consequently,to errors in estimated anisotropic *** this work,we relax the assumption of lateral homogeneity and discuss how to correct vertical seismic profile data for weak lateral *** describe a procedure of downward continuation of recorded traveltimes that accounts for the presence of both vertical inhomogeneity and weak lateral heterogeneity,which produces correct slowness surfaces at depths of downhole receivers,noticing that sufficiently dense receiver coverage along a borehole is required to separate influences of vertical and lateral heterogeneity on measured traveltimes and obtain accurate estimates of the slowness *** the slowness surfaces are found and a desired type of anisotropic model to be inverted is selected,the corresponding anisotropic parameters,providing the best fit to the estimated slownesses,can be *** invert the slowness surfaces of P-waves for parameters of the simplest anisotropic model describing dipping fractures(transversely isotropic medium with a tilted symmetry axis).Five parameters of this model,namely,the P-wave velocity v0 in the direction of the symmetry axis,Thomsen's anisotropic coefficients e and d,the tilt n,and the azimuth b of the symmetry axis,can be estimated in a stable manner when maximum source offset is greater than half of receiver depth.

关键词： Walkaway vertical seismic profile Lateral velocity heterogeneity Anisotropic parameter estimation vertical inhomogeneity

Liquid crystal immunosensors for the selective detection of Escherichia coli with a fast analysis tool

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Photonics Research 2024年第7期12卷 1564-1573页

作者： SANDRO C.OLIvEIRA MARIA S.SOARES BÁRBARA v.GONÇALvES ANDREIA C.M.RODRIGUES AMADEU M.v.M.SOARES RITA G.SOBRAL NUNO F.SANTOS JAN NEDOMA pedro L.ALMEIDA CARLOS MARQUES CICECO-Aveiro Institute of Materials Physics DepartmentUniversity of Aveiro3810-193 AveiroPortugal i3N Physics DepartmentUniversity of Aveiro3810-193 AveiroPortugal Associate Laboratory i4HB-Institute for Health and Bioeconomy School of Sciences and TechnologyNOVA University of Lisbon1099-085 LisbonPortugal CESAM-Centre for Environmental and Marine Studies and Department of Biology University of Aveiro3810-193 AveiroPortugal Department of Telecommunications VSB-Technical University of OstravaOstrava 70800Czech Republic i3N-CENIMAT School of Sciences and TechnologyNOVA University of Lisbon1099-085 LisbonPortugal UnIRE ISELPolytechnic Institute of Lisbon1549-020 LisbonPortugal Department of Physics VSB-Technical University of OstravaOstrava 70800Czech Republic

The consumption of contaminated food may cause serious illnesses,and traditional methods to detect Escherichia coli are still associated with long waiting times and high costs given the necessity to transport samples to specialized *** is a need to develop new technologies that allow cheap,fast,and direct monitoring at the site of ***,in this work,we developed optical immunosensors for the selective detection of ***,based on liquid crystal technology,whose molecules can align in different manners depending on the boundary conditions (such as substrates) as well as the environment that they *** glass substrate was functionalized with *** antibody using cysteamine as an intermediate,and a vertical alignment was imposed on the liquid crystal molecules by using DMOAP during *** presence of bacteria disrupts the alignment of the liquid crystal molecules,changing the intensity of light emerging between cross polarizers,measured using a polarized optical microscope and a *** was possible to detect *** in suspensions in the concentration range from 2.8 cells/mL to 2.8×10^(9) cells∕*** was also evaluated,and the sensors were used to analyze contaminated water samples.A prototype was developed to allow faster,in-situ,and easier analysis avoiding bulky instruments.

关键词： crystal alignment analysis

Determination of critical state line(CSL)for silty-sandy iron ore tailings subjected to low-high confining pressures

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第5期16卷 1684-1695页

作者： Nilo Cesar Consoli João vítor de Azambuja Carvalho Alexia Cindy Wagner Hugo Carlos Scheuermann Filho Inácio Carvalho pedro Pazzoto Cacciari João Paulo de Sousa Silva Civil Engineering Universidade Federal do Rio Grande do SulPorto AlegreRS90035-190Brazil Exploration and Mineral Projects-Mineral Development Centre VALE S.A.Santa LuziaMG33040-900Brazil Department of Civil Geological and Mining EngineeringPolytechnique MontrealQuebecH3C 3A7Canada

The disposal of filtered tailings in high dry stacks can induce particle breakage,changing the material's behaviour during the structure's *** grading changes influence material properties at the critical state,and this is not mature for intermediate artificial soils(tailings)in a broad range of confining *** this paper,it aims to describe the behaviour of iron ore tailings in a spectrum of confining pressures broader than the reported in previous studies.A series of consolidated drained(CD)triaxial tests was carried out with confining pressures ranging from 0.075 MPa to 120 *** results show that the amount of breakage plays an essential role in the response of iron ore *** existence of curved critical state line(CSL)in both specific volume(ν)-logarithm of mean effective stress(p′)and deviatoric stress(q)-mean effective stress(p′)planes,and different responses in the deviatoric stress-axial strain-volumetric strain curves were *** inverse S-shaped equation was proposed to represent the silty-sandy tailings'behaviour up to high pressures onν-lnp′*** proposed equation provides a basis for enhancing constitutive models and considers the evolution of the grading up to severe loading *** adjustment considered three regions with different responses associated with particle breakage at different pressure levels.

关键词： Tailings Iron ore tailings dry stacking Silty-sandy material Critical state soil mechanics High confining pressures Particle breakage

On the Restricted Arc-connectivity of s-geodetic Digraphs

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Acta Mathematica Sinica,English Series 2010年第10期26卷 1865-1876页

作者： Camino BALBUENA pedro GARCía.v.zquez Departament de Matemàtica Aplicada Ⅲ Universitat Politècnica de Catalunya Departamento de Matemática Aplicada I Universidad de Sevilla E.T.S. de Arquitectura

For a strongly connected digraph D the minimum ,cardinality of an arc-cut over all arc-cuts restricted arc-connectivity λ′（D） is defined as the S satisfying that D - S has a non-trivial strong component D1 such that D - v（D1） contains an arc. Let S be a subset of vertices of D. We denote by w＋（S） the set of arcs uv with u ∈ S and v S, and by w-（S） the set of arcs uv with u S and v ∈ S. A digraph D = （v, A） is said to be λ′-optimal if λ′（D） =ξ′（D）, where ξ′（D） is the minimum arc-degree of D defined as ξ（D） = min {ξ′（xy）： xy ∈ A}, and ξ′（xy） = min（｜ω＋（{x,y}）｜, ｜w-（{x,y}）｜, ｜w＋（x） ∪ w- （y）｜, ｜w- （x） ∪ω＋（y）｜}. In this paper a sufficient condition for a s-geodetic strongly connected digraph D to be λ′-optimal is given in terms of its diameter. Furthermore we see that the h-iterated line digraph Lh（D） of a s-geodetic digraph is λ′-optimal for certain iteration h.

关键词： Restricted arc-connectivity arc-cut diameter s-geodetic digraph line digraph

Effects of Phytoremediation on Soil Contaminated with Pb and Cd in Tolerant Bacterial Populations

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Journal of Environmental Science and Engineering(A) 2024年第4期13卷 122-127页

作者： Alejandra vásquez María Montes Melissa Cervantes María Alvarado pedro García victor Aguilar Department of Environmental Engineering Institute for EngineeringUniversity of VeracruzBoca del RioVer.94294Mexico Department Chemical Engineering Faculty of Chemical SciencesUniversity of VeracruzBoca del RíoVer.94294Mexico Faculty of Environmental Engineering Popular Autonomous University of the State of PueblaBarrio de Santiago 72410PueblaPueMexico Department of Administration Open Education SystemUniversity of VeracruzBoca del RioVer.94294Mexico

Bacterial populations isolated from treated soil,artificially contaminated with lead(Pb)and cadmium(Cd)and undergoing a phytoremediation process were studied to determine their potential application in soil *** physicochemical parameters evaluated in the soil varied *** bacterial strains were selected from each polluted soil to test tolerance and growth in contaminated *** concentrations of heavy metals tested were 1,000 ppm for lead and 850 ppm for *** strains were morphologically identified through Gram *** strains showing the most significant growth in both contaminants were then selected to verify their tolerance to different concentrations of heavy *** results demonstrated that the selected bacteria have high tolerance to Pb,resisting inhibition up to 2,000 *** contrast,strains exposed to cadmium tended to slow their growth as the concentration increased.

关键词： Lead cadmium soil bacteria remediation

CONSTANS alters the circadian clock in Arabidopsis thaliana

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Molecular Plant 2024年第8期17卷 1204-1220页

作者： pedro de los Reyes Gloria Serrano-Bueno Francisco J.Romero-Campero He Gao Jose M.Romero Federico valverde Plant Development Group-Institute for Plant Biochemistry and Photosynthesis Consejo Superior de Investigaciones CientificasUniversidad de SevillaSevilleSpain Department of Computer Science and Artificial Intelligence Universidad de SevillaSevilleSpain Department of Plant Developmental Biology Max Planck Institute for Plant Breeding ResearchCologneGermany Department of Plant Biochemistry and Molecular Biology Universidad de SevillaSevilleSpain

Plants are sessile organisms that have acquired highly plastic developmental strategies to adapt to the *** these processes,the floral transition is essential to ensure reproductive success and is finelyregulated by several internal andexternal genetic *** photoperiodic pathway,which controls plant response to day length,is one of the most important pathways controlling *** Arabidopsis photoperiodic flowering,CONSTANS(CO)is the central gene activating the expression of the florigen FLOWERING LOCUS T(FT)in the leaves at the end of a long *** circadian clock strongly regulates Co ***,to date,no evidence has been reported regarding a feedbackloop from the photoperiod pathway back to the circadian *** transcriptional networks,we have identified relevant network motifs regulating the interplay between the circadian clock and the photoperiod *** expression,chromatin immunoprecipitation experiments,and phenotypic analysis allowed us to elucidate the role of Co over the circadian *** with altered cO expression showed a different internal clock period,measured by daily leaf rhythmic *** showed that co upregulates the expression of key genes related to the circadian clock,such as CCA1,LHY,PRR5,and Gl,at the end of a long day by bindingto specific sites on their ***,a high numberof PRR5-repressed target genes are upregulated by CO,and this could explain the phase transition promoted by *** CO-PRR5 complex interacts with the bZiP transcriptionfactor HY5andhelps to localize the complex in the promoters of clock *** together,our results indicate that there may be a feedback loop in which co communicates back to the circadian clock,providing seasonal information to the circadian system.

关键词： CONSTANS circadian clock photoperiod

Clinical and Demographic Profile of Women with Uterine Fibroids Living in Puerto Rico

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Open Journal of Obstetrics and Gynecology 2024年第9期14卷 1347-1362页

作者： Edwin Y. Soto-velázquez Alexander J. Jaramillo-Cañas Shania N. Aponte-Paris Gabriela v. Martínez-Marrero Irazu S. Guinan Gabrielle A. Rivera-Maldonado Alexandra Novas pedro L. Cruz-Rosa Idhaliz Flores-Caldera Maricarmen Colón-Diaz Department of Physiology and Pathology San Juan Bautista School of Medicine Caguas Puerto Rico United States Ponce Research Institute Ponce Health Sciences University Ponce Puerto Rico United States

Introduction: Uterine leiomyomas, or fibroids, are prevalent benign tumors affecting up to 70% of reproductive-age women in the United States, significantly impacting productivity and quality of life. Despite their commonality, the epidemiology and clinical patterns of leiomyomas in Puerto Rico remain inadequately researched. Methods: This study conducted a secondary data analysis using clinical, menstrual cycle characteristics, and demographic data from self-administered questionnaires of women undergoing diagnostic laparoscopy for endometriosis in Puerto Rico. Chi-square tests and t-tests analyzed categorical and continuous variables, respectively (p Results: Among 1,610 endometriosis cases, 312 included uterine fibroids. Prevalence estimates were 10.3% (40 years). Primiparous women averaged 22.14 years, with 40.71% having 2 - 3 pregnancies and 26.28% experiencing miscarriages. Symptoms included infertility (29.5%), dyspareunia (40.7%), severe pain (50%), and dysmenorrhea (75.6%). Comorbidities included ovarian cysts (52.2%) and abnormal uterine bleeding (37.8%). Conclusions: Advanced age, parity, and comorbidities like diabetes and hypertension were prevalent in our cohort. Understanding the epidemiological profile of women living in Puerto Rico with uterine fibroids is crucial for improving diagnostic awareness and enhancing patient care.

关键词： Uterine Fibroids Puerto Rico Epidemiology Dysmenorrhea Abnormal Uterine Bleeding

Solar-assisted photocatalytic water splitting using defective UiO-66 solids from modulated synthesis

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Nano Research 2024年第5期17卷 4134-4150页

作者： Celia M.Rueda-Navarro María Cabrero-Antonino Paula Escamilla valentín Díez-Cabanes Dong Fan pedro Atienzar Belén Ferrer Ignacio vayá Guillaume Maurin Herme G.Baldoví Sergio Navalón Departamento de Química Universitat Politècnica de ValènciaCamino de Vera s/nValencia 46022Spain Instituto de Ciencia Molecular(ICMOL) Universitat de ValènciaPaterna 46980Spain ICGM Univ.MontpellierCNRSENSCMMontpellier34095France Instituto de Tecnología Química(UPv-CSIC) Universitat Politècnica de ValènciaAvenida de los Naranjos s/nValencia 46022Spain

Metal-organic frameworks(MOFs)are attracting increasing interests as photocatalysts for solar-driven hydrogen production from *** paper reports on a comparative study of using either acetic acid(AA)or trifluoroacetic acid(TFA)as the representative UiO-66 organic modulators for synthesizing visible light responsive UiO-66(Zr)-X(X:NH_(2) or NO_(2))photocatalysts for water *** results show that photocatalytic hydrogen generation from a water/methanol mixture can be improved by varying the nature and amount of the modulator employed to prepare the different UiO-66(Zr)-X(X:NH_(2) or NO_(2))solid ***-66(Zr)-NH_(2) was the most active photocatalyst,followed by UiO-66(Zr)-NO_(2),both prepared with 12 equivalents of AA with respect to the organic *** UiO-66(Zr)-NH_(2) solid was more active than the parent MOF in photocatalytic overall water splitting(OWS)(H_(2) and O_(2) production of 450 and 160μmol·g^(-1),respectively,in 5 h;apparent quantum yield(AQY)at 400 nm of 0.06%)in the absence of methanol and compares favourably with analogous *** on the photocatalytic activity of the most active solids of both series was obtained by means of a series of techniques,including ultraviolet-visible(Uv-vis)diffuse reflectance,X-ray photoelectron spectroscopy(XPS),laser flash photolysis(LFP),electron spin resonance(ESR),photoluminescence and photoelectrochemical measurements together with density functional theory(DFT)*** results showed that organic acid modulators can be used to enhance the photocatalytic activity of missing linker UiO-66 defective materials in solar-powered water splitting.

关键词： heterogeneous photocatalysis metal-organic frameworks(MOFs) UiO-66 materials carboxylic acid modulators water splitting solar light