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Nonlinear forced vibration in a subcritical regime of a porous functionally graded pipe conveying fluid with a retaining clip

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Applied mathematics and mechanics(English Edition) 2025年第1期46卷 101-122页

作者： m.GHOLAmI m.EFTEKHARI Department of mechanical Engineering Shahid Bahonar University of Kerman

This study examines the nonlinear behaviors of a clamped-clamped porous pipe made of a functionally graded material(FGm) that conveys fluids and is equipped with a retaining clip, focusing on primary resonance and subcritical dynamics. The nonlinear governing equations for the FGm pipe are derived by the extended Hamilton's principle, and subsequently discretized through the application of the Galerkin *** direct method of multi-scales is then used to solve the derived equations. A thorough analysis of various parameters, including the clip stiffness, the power-law index, the porosity, and the clip location, is conducted to gain a comprehensive understanding of the system's nonlinear dynamics. Through the analysis of the first natural frequency, the study highlights the influence of the flow velocity and the clip stiffness, while the comparisons with metallic pipes emphasize the role of FGm composition. The examination of the forced response curves reveals saddle-node bifurcations and their dependence on parameters such as the detuning parameter and the power-law index, offering valuable insights into the system's nonlinear resonant behavior. Furthermore, the frequency-response curves illustrate the hardening nonlinearities influenced by factors such as the porosity and the clip stiffness, revealing nuanced effects on the system response and resonance characteristics. This comprehensive analysis enhances the understanding of nonlinear behaviors in FGm porous pipes with a retaining clip, providing key insights for practical engineering applications in system design and optimization.

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Link between caries,periodontitis,and pregnancy:The role of personalized oral hygiene

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World Journal of Clinical Cases 2025年第6期13卷 51-57页

作者： melissa martínez Nieto martha Leticia De León rodríguez Francisco Javier Alcaraz Baturoni Alma Alicia Soto Chávez Sarah monserrat Lomelímartínez Periodontics Program Department of Integrated Dentistry ClinicsCentro Universitario de Ciencias de la SaludUniversidad de GuadalajaraGuadalajara 44340Mexico Department of medical and Life Sciences Centro Universitario de la CiénegaUniversidad de GuadalajaraOcotlán 47810JaliscoMexico master of Public Health Department of Well-being and SustainableCentro Universitario del NorteUniversidad de GuadalajaraColotlán 46200Mexico

Optimal health during pregnancy is crucial for ensuring the well-being of the mother and the developing *** article is focused on the impact of oral health and the role of personalized oral hygiene management in addressing prevalent dental issues among pregnant women,with particular emphasis on periodontal disease and dental *** the high prevalence of these dental problems and their association with obstetric complications such as pre-term birth and low birth weight,many pregnant women do not receive adequate dental *** gap in care is often due to misconceptions about the safety of dental treat-ments during pregnancy and lack of awareness on the part of healthcare *** of the impacts of oral health and personalization of oral hygiene strategies such as tailored education and support,have proven effective in improving oral health in this *** reductions in the incidence of caries and periodontal disease may be achieved by adapting care to the specific needs of each patient,thereby enhancing maternal and fetal health *** of personalized oral hygiene management into maternal health pro-grams and enhancement of ongoing education for pregnant women and healthcare professionals are essential steps in the reduction of pregnancy-related risks and improvement of maternal and neonatal *** Tip:In this article,we reviewed a recent study on the effects of personalized oral hygiene management on the oral health of pregnant women,as discussed in the article by men et *** study demonstrated that personalized oral hygiene interventions significantly improved oral health outcomes during pregnancy by reducing the prevalence of dental caries and periodontal *** emphasized the importance of individualized oral care programs that integrate education and tailored support,and we highlighted their significance in enhancing maternal and fetal *** approach underscores the need for

关键词： Pregnancy Periodontal disease Periodontitis Dental caries Oral hygiene

Neurogenesis dynamics in the olfactory bulb:deciphering circuitry organization, function, and adaptive plasticity

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Neural Regeneration Research 2025年第6期20卷 1565-1581页

作者： moawiah m.Naffaa Department of Psychology and Neuroscience Duke UniversityDurhamNCUSA Department of Cell Biology Duke University School of MedicineDurhamNCUSA

Adult neurogenesis persists after birth in the subventricular zone, with new neurons migrating to the granule cell layer and glomerular layers of the olfactory bulb, where they integrate into existing circuitry as inhibitory interneurons. The generation of these new neurons in the olfactory bulb supports both structural and functional plasticity, aiding in circuit remodeling triggered by memory and learning processes. However, the presence of these neurons, coupled with the cellular diversity within the olfactory bulb, presents an ongoing challenge in understanding its network organization and function. moreover,the continuous integration of new neurons in the olfactory bulb plays a pivotal role in regulating olfactory information processing. This adaptive process responds to changes in epithelial composition and contributes to the formation of olfactory memories by modulating cellular connectivity within the olfactory bulb and interacting intricately with higher-order brain regions. The role of adult neurogenesis in olfactory bulb functions remains a topic of debate. Nevertheless, the functionality of the olfactory bulb is intricately linked to the organization of granule cells around mitral and tufted cells. This organizational pattern significantly impacts output, network behavior, and synaptic plasticity, which are crucial for olfactory perception and memory. Additionally, this organization is further shaped by axon terminals originating from cortical and subcortical regions. Despite the crucial role of olfactory bulb in brain functions and behaviors related to olfaction, these complex and highly interconnected processes have not been comprehensively studied as a whole. Therefore, this manuscript aims to discuss our current understanding and explore how neural plasticity and olfactory neurogenesis contribute to enhancing the adaptability of the olfactory system. These mechanisms are thought to support olfactory learning and memory, potentially through increased

关键词： network adaptability neurogenesis neuronal communication olfactory bulb olfactory learning olfactory memory synaptic plasticity

Fungal contamination of stored automobile-fuels in a tropical environment

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Journal of Environmental Sciences 2010年第10期22卷 1595-1601页

作者： Carlos E.rodríguez-rodríguez Evelyn rodríguez Rigoberto Blanco Ivannia Cordero Daniel Segura Research Center in Tropical Diseases and Laboratory of Research in Anaerobic Bacteriology Faculty of MicrobiologyUniversity of Costa Rica Department of Chemical Engineering School of EngineeringAutonomous University of Barcelona Research Center in Electrochemistry and Chemical Energy University of Costa Rica

Because of the lack of reports, the base levels of microbial contamination on stored fuels are unknown in tropical regions and it is unclear whether these levels have some influence on fuel quality parameters. Therefore, fungal quality in automobile fuels stored across Costa Rican territory was evaluated during two years according to the standard ASTm D6974-04. For a total of 96 samples, counts and identification of molds and yeasts were performed on regular gas, premium gas and diesel taken from the bottom and superior part of the container tanks. The highest contamination was found on the bottom of the tanks, where an aqueous phase was usually identified, showing populations over the ones present in the hydrocarbon itself （up to 108 CFU/L）. Diesel was the most contaminated fuel （up to 107 CFO/L）; however, an alteration on the physicochemical parameters was not observed in any kind of fuel. Seventy-five mold strains were isolated, Penicillium sp. being the most common genus （45.8% of the samples）, and ten yeast strains, from the genera Candida sp. and Rhodotorula sp. Four of the yeasts were able to grow on diesel as the sole carbon source, at concentrations ranging from 0.5% to 25%. Increasing the frequency of tank cleaning, adding antimicrobial agents and monitoring microbial populations are recommended strategies to improve microbial quality of stored fuels.

关键词： fuel microbial contamination biodegradation molds yeasts

Plateau archives of lithosphere dynamics,cryosphere and paleoclimate:The formation of Cretaceous desert basins in east Asia

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Geoscience Frontiers 2022年第6期13卷 170-181页

作者： Chihua Wu Juan Pedro rodríguez-López m.Santosh State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Chengdu University of TechnologyChengdu 610059China PAGODA Research Group(Plateau&Global Desert Basins Research Group) Institute of Sedimentary GeologyChengdu University of TechnologyChengdu 610059China Permafrost Laboratory Department of GeographyUniversity of SussexFalmerBrighton BN19SJUnited Kingdom School of Earth Science and Resources China University of Geosciences29 Xueyuan RoadBeijing 100083China Department of Earth Sciences University of AdelaideSA 5005Australia

Southeastern Eurasia is a global window to the Cretaceous paleoclimate and lithosphere *** contains one of the most complete and complex sedimentary records of mesozoic desert basins on planet *** this study,we perform the spatio-temporal tracking of 96 Cretaceous palaeoclimate indicators during 79 myr which reveal that the plateau paleoclimate archives from East Asia resulted from an Early to mid-Cretaceous ocean–atmosphere coupling and a shift to a preponderant role of Late Cretaceous lithosphere dynamics and tectonic forcing on high-altitude depositional systems linked to the subduction margins of the Tethys and Paleo-Pacific realms beneath the Eurasian *** crustal response to tectonic processes linked with the spatio-temporal evolution of the Tethyan and Paleo-Pacific margins defined the configuration of major sedimentary basins on this *** significant increase and decrease in the number of active sedimentary basins that occur during the Cretaceous,from 16 in the Early Cretaceous,to 28 in the mid-Cretaceous,and a decreasing to 20 sedimentary basins in the Late Cretaceous,is a direct response of lithospheric dynamics associated with the two main subduction zones(Tethys and Pacific domains).A shift in subduction style from an Early Cretaceous Paleo-Pacific Plate slab roll back to a Late Cretaceous flat-slab mode might have triggered regional plateau uplift,blocked intraplate volcanism,thus enhancing the denudation and sediment availability,and created wind corridors that led to the construction and accumulation of extensive Late Cretaceous aeolian sandy deserts(ergs)that covered mid-Cretaceous plateau *** the same time,plateau uplift associated with crustal thickening following terrane assembly in the Tethyan margin triggered altitudinal cryospheric processes in sandy desert *** of an active Cretaceous cryosphere in China include ValanginianHauterivian glacial debris flows,Early Aptian geochemical signature of melt w

关键词： Cretaceous Cryosphere Aeolian Plateau Subduction Asia

mitochondria–cGAS–STING axis is a potential therapeutic target for senescence-dependent inflammaging-associated neurodegeneration

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Neural Regeneration Research 2025年第3期20卷 805-807页

作者： Josém.Izquierdo Centro de Biología molecular Severo Ochoa(CBm) Consejo Superior de Investigaciones Científicas-Universidad Autónoma de Madrid(CSIC-UAM)MadridSpain

The word “senescence” comes from the Latin senescens, meaning “to begin to age”, and is characterized by a long-lasting but reversible block in proliferation, resulting from stress-induced cell cycle arrest of pre... 详细信息

关键词： Latin potential lasting

magnetic filtration of an iron oxide aerosol by means of magnetizable grates

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China Particuology 2007年第1期5卷 140-144页

作者： A. Alvaro J.m. rodríguez Paulo A. Augusto A.m. Estvez Department of Chemical Engineering University of Salamanca Plaza de los Caídos 1-5 37008 Salamanca Spain Department of Chemical Engineering University of Salamanca Plaza de los Caídos 1-5 37008 Salamanca Spain Department of Chemical Engineering Faculty of Engineering University of Porto Rua Dr. Roberto Frias 4200-465 Porto Portugal

The cleaning of gases with low concentrations of small ferromagnetic or paramagnetic particles is a difficult task for conventional filtration. A new alternative procedure, magnetic filtration, is used in this work. Iron oxide aerosol was generated by elutriation of iron oxide particles from a fluidized bed consisting of a mixture of Geldart-C iron oxide powder and large spherical Geldart-B sand particles. The aerosol was filtered by means of a magnetic filter which consisted of one, two or three iron grates staggered to each other. The experimental installation contained also an isokinetic sampling system and a microtrac SRA 150 Particle Analyser. A theoretical expression for filtration efficiency was deduced from a previous model taking into account the different forces acting on the iron oxide particles. Experimental filtration efficiency matches quite well calculated theoretical efficiency. It was found that an increase in particle size, in thee number of grates or in the applied magnetic field produced higher filtration efficiencies up to 100% in some cases. In all filtration experiments pressure drop through the magnetic filter was very small.

关键词： Iron oxide aerosol magnetic filtration Iron grates

Electron states and electron Raman scattering in semiconductor double cylindrical quantum well wire

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Chinese Physics B 2016年第11期25卷 453-460页

作者： m.m.nguía-rodríguez Ri Betancourt-Riera Re Betancourt-Riera R Riera J m Nieto Jalil Departamento de Investigación en Física Universidad de Sonora Apartado Postal 5-88 83190 Hermosillo Sonora México Instituto Tecnológico de Hermosillo. Avenida Tecnologico S/N Col. Sahuaro 83170 Hermosillo Sonora México Tecnológico de monterrey-Campus Sonora Norte. Bulevar Enrique mazón Lopez No. 965 83000 Hermosillo Sonora México

The differential cross section for an electron Raman scattering process in a semiconductor GaAs/AlGaAs double quantum well wire is calculated,and expressions for the electronic states are *** system is modeled by considering T = 0 K and also with a single parabolic conduction band,which is split into a subband system due to the *** gain and differential cross-section for an electron Raman scattering process are *** addition,the emission spectra for several scattering configurations are discussed,and interpretations of the singularities found in the spectra are *** electron Raman scattering studied here can be used to provide direct information about the efficiency of the lasers.

关键词： Electron cylindrical confinement conduction radius decoupling AlGaAs parabolic modeled resonant

Improved deterministic and stochastic models for simulating partial discharges in non‐conducting trees inside solid dielectrics

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High Voltage 2021年第1期6卷 82-94页

作者： Johnatan m.rodríguez‐Serna Ricardo Albarracín‐Sánchez Department of Electrical and Electronic Engineering Automatic Controland Applied PhysicsSchool of Industrial Design and Engineering(ETSIDI)Universidad Politécnica de Madrid(UPM)MadridSpain Department of Electrical Engineering Universidad de AntioquiaMedellínColombia

Electrical trees are defects originated and driven by partial discharges(PD)activity and this is the reason why their modelling and simulation are fundamental for the ageing mechanisms comprehension and diagnosis analyses of insulation systems compound by solid *** study presents a brief review of the different models implemented to simulate PD in electrical trees inside solid *** addition,an improved deterministic model as well as a stochastic model are presented,which allow predicting adequately the PD pulses distribution,in magnitudes and phase,for non‐conducting electrical trees of different shape and *** case studies were simulated and their results exhibit good agreement when compared with measurements presented in the *** is concluded that the main parameters that state the PD behaviour in trees are the inception and extinction voltage mag-nitudes,including their probability distributions,and the tree *** models can be used for prognosis analysis based on on‐line measurements.

关键词： solid conducting electrical