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Communications in Theoretical Physics 2024年第4期76卷 22-31页

作者： Yusry o El-Dib Department of Mathematics Faculty of EducationAin Shams UniversityRoxyCairoEgypt

The time-delayed fractal Van der Pol–Helmholtz–Duffing(VPHD)oscillator is the subject of this paper,which explores its mechanisms and highlights its stability *** time-delayed technologies are currently garnering significant attention,the focus of this research remains crucially relevant.A non-perturbative approach is employed to refine and set the stage for the system under *** innovative methodologies introduced yield an equivalent linear differential equation,mirroring the inherent nonlinearities of the ***,the incorporation of quadratic nonlinearity into the frequency formula represents a cutting-edge *** analytical solution's validity is corroborated using a numerical *** conditions are ascertained through the residual Galerkin ***,it is observed that the delay parameter,in the context of the fractal system,reverses its stabilizing influence,impacting both the amplitude of delayed velocity and the *** analytical solution's precision is underscored by its close alignment with numerical ***,the study reveals that fractal characteristics emulate damping *** its applicability across diverse nonlinear dynamical systems,this non-perturbative approach emerges as a promising avenue for future research.

关键词： Van der Pol-Helmholtz-Duffing oscillator fractal space time-delay non-perturbative approach stability analysis El-Dib's frequency formula

Sensing nanoscale electromagnetic forces when the heat is on

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national Science Review 2024年第7期11卷 64-65页

作者： Eric o.Potma Department of Chemistry University of California

In scanning probe microscopy(SPM),a sharp tip scans across a sample to produce an image with nanometer-scale resolution or better. SPM contrast is derived from the physical interplay between the tip and the sample. A special class of SPM techniques measures forces when the tip–sample junction is illuminated by an external light source. Photo-induced forces can be sensitive to the optical properties of the sample, thus enabling nanoscale imaging with spectroscopic,material-specific contrast.

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Clinical and demographic features of patients undergoing videocapsule endoscopy management:A descriptive study

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World Journal of gastrointestinal Endoscopy 2024年第7期16卷 424-431页

作者： María C Mejía Luis G Piñeros Luis M Pombo Laura A León Jenny A Velásquez Aníbal A Teherán Karen P Ayala Research Center Fundación Universitaria Juan N.CorpasBogotá111321Colombia Fundación Universitaria Juan n.Corpas Bogotá111321Colombia Department of gastroenterology Universidad Militar Nueva GranadaBogotá111711Colombia Department of gastroenterology Hospital Universitario Clínica San RafaelBogotá111711Colombia

BACKGRoUnD Video-capsule endoscopy(VCE)is an efficient tool that has proven to be highly useful in approaching several gastrointestinal *** was implemented in Colombia in 2003,however current characterization of patients undergoing VCE in Colombia is limited,and mainly comes from two investigations conducted before the SARS-CoV-2 pandemic *** To describe the characteristics of patients undergoing VCEs and establish the main indications,findings,technical limitations,and other outstanding *** A descriptive study was carried out using data from reports of VCE(PillCam SB3 system)use in a gastroenterology Unit in Bogotá,Colombia between September 2019 and January *** and clinical variables such as indication for the VCE,gastric and small bowel transit times(GTT,SBTT),endoscopic preparation quality,and limitations were described[n(%),median(IQR)].RESULTS A total of 133 VCE reports were *** were in men with a median age of 70 *** majority had good preparation(96.2%),and there were technical limitations in 15.8%of *** main indications were unexplained anemia(91%)or occult bleeding(23.3%).The median GTT and SBTT were 14 and 30 minutes,*** frequencies of bleeding stigma(3.79%)and active bleeding(9.09%)were low,and the most frequent abnormal findings were red spots(28.3%),erosions(17.6%),and vascular ectasias(12.5%).ConCLUSIon VCE showed high-level *** main indication was unexplained *** bleeding was the most frequent *** with artificial intelligence,VCE can improve diagnostic precision and targeted therapeutic interventions.

关键词： Endoscopy Video-capsule endoscopy Capsule endoscopy gastrointestinal diseases observational study gastrointestinal bleeding

Resilience to structural and molecular changes in excitatory synapses in the hippocampus contributes to cognitive function recovery in Tg2576 mice

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neural Regeneration Research 2024年第9期19卷 2068-2074页

作者： Carolina Aguado Sara Badesso JoséMartínez-Hernández Alejandro Martín-Belmonte Rocío Alfaro-Ruiz Miriam Fernández Ana Esther Moreno-Martínez Mar Cuadrado-Tejedor Ana García-osta Rafael Luján Synaptic Structure Laboratory Instituto de Investigación en Discapacidades Neurológicas(IDINE)Department of Medical SciencesFacultad de MedicinaUniversidad de Castilla-La ManchaCampus BiosanitarioAlbaceteSpain Gene Therapy for neurological Disease Program Center for Applied Medical Research(CIMA)University of NavarraInstituto de Investigación Sanitaria de Navarra(IdiSNA)PamplonaSpain Pharmacology Unit Department of Pathology and Experimental TherapeuticsFaculty of Medicine and Health SciencesInstitute of NeurosciencesUniversity of BarcelonaBarcelonaSpain neuropharmacology and Pain Group Neuroscience ProgramInstitut d’InvestigacióBiomèdica de BellvitgeIDIBELLL’Hospitalet de LlobregatSpain Department of Pathology Anatomy and PhysiologySchool of MedicineUniversity of NavarraPamplonaSpain UniversitéGrenoble Alpes Grenoble Institut des NeurosciencesGrenobleFrance

Plaques of amyloid-β(Aβ)and neurofibrillary tangles are the main pathological characteristics of Alzheimer’s disease(AD).However,some older adult people with AD pathological hallmarks can retain cognitive *** the factors that lead to this cognitive resilience to AD offers promising prospects for identifying new therapeutic *** hypothesis focuses on the contribution of resilience to changes in excitatory synapses at the structural and molecular levels,which may underlie healthy cognitive performance in aged AD *** the Morris Water Maze test,we selected resilient(asymptomatic)and cognitively impaired aged Tg2576 *** the enzyme-linked immunosorbent assay showed similar levels of Aβ42 in both experimental groups,western blot analysis revealed differences in tau pathology in the pre-synaptic supernatant *** further investigate the density of synapses in the hippocampus of 16-18 month-old Tg2576 mice,we employed stereological and electron microscopic *** findings indicated a decrease in the density of excitatory synapses in the stratum radiatum of the hippocampal CA1 in cognitively impaired Tg2576 mice compared with age-matched resilient Tg2576 and non-transgenic ***,through quantitative immunoelectron microscopy in the hippocampus of impaired and resilient Tg2576 transgenic AD mice,we uncovered differences in the subcellular localization of glutamate ***,the density of GluA1,GluA2/3,and mGlu5 in spines and dendritic shafts of CA1 pyramidal cells in impaired Tg2576 mice was significantly reduced compared with age-matched resilient Tg2576 and non-transgenic ***,the density of GluA2/3 in resilient Tg2576 mice was significantly increased in spines but not in dendritic shafts compared with impaired Tg2576 and non-transgenic *** subcellular findings strongly support the hypothesis that dendritic spine plasticity and synaptic machinery in the hippocampus play cr

关键词： aging Alzheimer´s disease cognitive hippocampus immunoelectron microscopy resilience synapse

From BIM model to 3D construction printing:A framework proposal

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Frontiers of Architectural Research 2024年第4期13卷 912-927页

作者： Rodrigo García-Alvarado Pedro Soza Ginnia Moroni Fernando Pedreros Martín Avendaño Pablo Banda Cristian Berríos Depto.Diseño y Teoría de La Arquitectura Universidad Del Bío-BíoConcepciónChile Depto.Arquitectura Universidad de ChileSantiagoChile Facultad de Ingeniería Arquitectura y DiseñoUniversidad San SebastiánConcepciónChile Facultad de Arquitectura Arte y DiseñoUniversidad Diego PortalesSantiagoChile

The growth of 3D construction printing needs appropriate integration into the planning and execution phases of building *** this aim,the Architecture,Engineering,and Construction sector(AEC)has been increasingly adopting building information modeling(BIM)systems to synchronize design and construction *** study proposes a technical workflow to manage 3D construction printing into BIM models,evaluating various procedures according to construction element *** on mature software platforms,the research details the data transfer process using a case study of a single-story *** case delves into design procedures for constructing walls of varied shapes,adjustments in width,joints,openings,textures,fillings,and the insertion of reinforcements and services while also discussing requirements of other building *** steps for managing design information and controlling printing machines are *** study’s outcome presents a comprehensive information flow,encompassing model segmentation,geometric data transfer,adjustments of details,and the generation of printing ***,it is offered a discussion that underlines the importance of a synergistic digital information flow that merges both design and execution phases,promoting construction efficiency and the embrace of innovative *** contribution of the paper focuses on technical design strategies for 3D construction printing,but also on suggesting an integrated process.

关键词： 3D construction printing Additive manufacturing Architectural design BIM

Unifying concepts in methanogenic,aerobic,and anammox sludge granulation

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Environmental Science and Ecotechnology 2024年第1期17卷 17-30页

作者： Simon Mills Anna Christine Trego Marco Prevedello Jo De Vrieze Vincent o’Flaherty Piet n.L.Lens Gavin Collins Microbial Communities Laboratory School of Biological and Chemical SciencesNational University of Ireland GalwayUniversity RoadGalwayH91 TK33Ireland Microbial Ecology Laboratory School of Biological and Chemical Sciences University of GalwayUniversity RoadGalwayH91 TK33Ireland Center for Microbial Ecology and Technology(CMET) Ghent UniversityCoupure Links 653B-9000GentBelgium University of Galway University RoadGalwayH91 TK33Ireland

The retention of dense and well-functioning microbial biomass is crucial for effective pollutant removal in several biological wastewater treatment *** solids retention is often achieved through aggregation of microbial communities into dense,spherical aggregates known as granules,which were initially discovered in the *** granules have since been widely applied in upflow anaerobic digesters for waste-to-energy ***,granular biomass has been applied in aerobic wastewater treatment and anaerobic ammonium oxidation(anammox)*** mechanisms underpinning the formation of methanogenic,aerobic,and anammox granules are the subject of ongoing *** each granule type has been extensively studied in isolation,there has been a lack of comparative studies among these granulation *** is likely that there are some unifying concepts that are shared by all three sludge *** these unifying concepts could allow a unified theory of granulation to be ***,we review the granulation mechanisms of methanogenic,aerobic,and anammox granular sludge,highlighting several common concepts,such as the role of extracellular polymeric substances,cations,and operational parameters like upflow velocity and shear *** have then identified some unique features of each granule type,such as different internal structures,microbial compositions,and quorum sensing ***,we propose that future research should prioritize aspects of microbial ecology,such as community assembly or interspecies interactions in individual granules during their formation and growth.

关键词： Granule Granulation Anaerobic digestion Anammox Aerobic granule

Chebyshev polynomial-based Ritz method for thermal buckling and free vibration behaviors of metal foam beams

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Applied Mathematics and Mechanics(English Edition) 2024年第5期45卷 891-910页

作者： n.D.nGUYEn T.n.nGUYEn Faculty of Civil Engineering Ho Chi Minh City University of Technology and EducationHo Chi Minh City 71309Viet Nam Faculty of Engineering and Technology Kien Giang UniversityChau Thanh 92000Viet Nam

This study presents the Chebyshev polynomials-based Ritz method to examine the thermal buckling and free vibration characteristics of metal foam *** analyses include three models for porosity distribution and two scenarios for thermal *** material properties are assessed under two conditions,i.e.,temperature dependence and temperature *** theoretical framework for the beams is based on the higher-order shear deformation theory,which incorporates shear deformations with higher-order *** governing equations are established from the Lagrange equations,and the beam displacement fields are approximated by the Chebyshev *** simulations are performed to evaluate the effects of thermal load,slenderness,boundary condition(BC),and porosity distribution on the buckling and vibration behaviors of metal foam *** findings highlight the significant influence of temperature-dependent(TD)material properties on metal foam beams'buckling and vibration responses.

关键词： Ritz method Chebyshev function buckling vibration metal foam beam higher-order beam theory(HoBT)

DnA metabarcoding reveals seasonal changes in diet composition across four arthropod-eating lizard species(Phrynosomatidae:Sceloporus)

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Integrative Zoology 2024年第3期19卷 480-495页

作者： Mauricio HERnÁnDEZ Stephanie HEREIRA-PACHECo Antton ALBERDI Aníbal H.DÍAZ DE LA VEGA-PÉREZ Arturo ESTRADA-ToRRES Sergio AnConA Yendi E.nAVARRo-noYA Doctorado en Ciencias Biológicas Centro Tlaxcala de Biología de la ConductaUniversidad Autónoma de TlaxcalaTlaxcalaMexico Estación Científica La Malinche Centro Tlaxcala de Biología de la ConductaUniversidad Autónoma de TlaxcalaTlaxcalaMexico Center for Evolutionary Hologenomics The Globe InstituteUniversity of CopenhagenCopenhagenDenmark Consejo nacional de Ciencia y Tecnología-Centro Tlaxcala de Biología de la Conducta Universidad Autónoma de TlaxcalaTlaxcalaMexico Departamento de Ecología Evolutiva Instituto de EcologíaUniversidad Nacional Autónoma de MéxicoMexico CityMexico Laboratorio de Interacciones Bióticas Centro de Investigación en Ciencias BiológicasUniversidad Autónoma de TlaxcalaSan Felipe IxtacuixtlaTlaxcalaMexico

Diet composition and its ecological drivers are rarely investigated in coexisting closely related *** used a molecular approach to characterize the seasonal variation in diet composition in four spiny lizard species inhabiting a mountainous *** metabarcoding revealed that the lizards Sceloporus aeneus,***,***,and *** mostly consumed arthropods of the orders Hemiptera,Araneae,Hymenoptera,and *** terrestrial lizards *** and *** mostly predated ants and spiders,whereas the arboreal–saxicolous *** and saxicolous *** largely consumed grasshoppers and *** taxonomic and phylogenetic diversity of the prey was higher during the dry season than the rainy season,likely because reduced prey availability in the dry season forced lizards to diversify their diets to meet their nutritional *** and phylogenetic composition varied seasonally depending on the species,but only dietary composition varied with *** dietary turnover was greater in *** than in ***,suggesting site-specific seasonal variability in prey availability;no other differences among species were ***,which lives at the highest altitude in our study site,displayed interseasonal variation in diet *** differences were correlated with the species’feeding strategies and elevational distribution,which likely contributed to the coexistence of these lizard species in the studied geographic area and beyond.

关键词： arthropod-eating lizards diet breadth environmental barcoding mountainous ecosystem seasonal dietary shifts

Sociodemographic determinants associated with breastfeeding in term infants with low birth weight in Latin American countries

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World Journal of Clinical Pediatrics 2024年第1期13卷 141-149页

作者： Carlos Javier Avendaño-Vásquez Magda Liliana Villamizar-osorio Claudia Jazmin niño-Peñaranda Judith Medellín-olaya nadia Carolina Reina-Gamba School of nursing Antonio Nariño UniversityBogotá111511Colombia School of nursing Universidad Cooperativa de ColombiaBucaramanga 102536Colombia School of nursing Universidad Nacional de ColombiaColombia 111511Colombia

BACKGRoUnD A progressive decrease in exclusive breastfeeding(BF)is observed in Latin America and the Caribbean compared with global *** possibility of being breastfed and continuing BF for>6 months is lower in low birth weight than in healthy-weight *** To identify factors associated with BF maintenance and promotion,with particular attention to low-and middle-income countries,by studying geographic,socioeconomic,and individual or neonatal health *** A scoping review was conducted in 2018 using the conceptual model of social determinants of health published by the Commission on Equity and Health Inequalities in the United *** extracted data with common characteristics were synthesized and categorized into two main themes:(1)Sociodemographic factors and proximal determinants involved in the initiation and maintenance of BF in low-birth-weight term infants in Latin America;and(2)individual characteristics related to the self-efficacy capacity for BF maintenance and adherence in low-birth-weight term *** This study identified maternal age,educational level,maternal economic capacity,social stratum,exposure to BF substitutes,access to BF information,and quality of health services as mediators for maintaining *** Individual self-efficacy factors that enable BF adherence in at-risk populations should be analyzed for better health outcomes.

关键词： Breastfeeding Low birth weight Latin America Self-efficacy Social determinants of health

High-repetition-rate source of nanosecond duration kA-current pulses driven by relativistic laser pulses

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High Power Laser Science and Engineering 2024年第3期12卷 106-115页

作者： Michael Ehret Jakub Cikhardt Philip Wykeham Bradford Iuliana-Mariana Vladisavlevici Tomas Burian Diego de Luis Jose Luis Henares Rubén Hernández Martín Jon Imanol Apiñaniz Roberto Lera JoséAntonio Pérez-Hernández João Jorge Santos Giancarlo Gatti Centro de Láseres Pulsados(CLPU) VillamayorSpain Czech Technical University in Prague Faculty of Electrical EngineeringPragueCzech Republic Univ.Bordeaux-CnRS-CEA Centre Lasers Intenses et Applications(CELIA)UMR 5107TalenceFrance Department of Radiation and Chemical Physics FZU-Institute of Physics of the Czech Academy of SciencesPragueCzech Republic

We report the first high-repetition-rate generation and simultaneous characterization of nanosecond-scale return currents of kA-magnitude issued by the polarization of a target irradiated with a PW-class high-repetition-rate titanium:sapphire laser system at relativistic *** present experimental results obtained with the VEGA-3 laser at intensities from5×10^(18)to 1.3×10^(20)W cm^(-2).A non-invasive inductive return-current monitor is adopted to measure the derivative of return currents of the order of kA ns-1and analysis methodology is developed to derive return *** compare the current for copper,aluminium and Kapton targets at different laser *** data show the stable production of current peaks and clear prospects for the tailoring of the pulse shape,which is promising for future applications in highenergy-density science,for example,electromagnetic interference stress tests,high-voltage pulse response measurements and charged particle beam *** compare the target discharge of the order of hundreds of nC with theoretical predictions and a good agreement is found.

关键词： current pulses electromagnetic pulse application high-power laser relativistic laser plasma