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The effectiveness of different wear indicators in quantifying wear on railway wheels of freight wagons

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Railway Engineering Science 2024年第3期32卷 307-323页

作者： Philipe augusto de Paula Pacheco M.Magelli Matheus Valente Lopes pedro Henrique Alves Correa N.Zampieri N.Bosso Auteliano Antunes dos Santos Federal Institute of the Southeast of Minas Gerais(IF Sudeste MG) Técnico PanamáStreet 45Santos DumontMG 36246-311Brazil Railway Laboratory(Lafer) Universidade Estadual de Campinas(UNICAMP)Mendeleyev Street 200CampinasSP 13083-872Brazil Department of Mechanical and Aerospace Engineering Politecnico Di TorinoC.so Duca degli Abruzzi 2410129 TurinItaly

Railway infrastructure relies on the dynamic interaction between wheels and rails;thus,assessing wheel wear is a critical aspect of maintenance and *** paper focuses on the wheel-rail wear indicator T-gamma(Tγ).Amidst its use,it becomes apparent that Tγ,while valuable,fails to provide a comprehensive reflection of the actual material removal and actual contact format,which means that using only Tγas a target for optimization of profiles is not *** this work,three different freight wagons are evaluated:a meter-gauge and a broad-gauge heavy haul vehicles from South American railways,and a standard-gauge freight vehicle operated in Europe,with different axle loads and dissimilar new wheel/rail *** vehicles are subjected to comprehensive multibody simulations on various *** simulations aimed to elucidate the intricate relationship between different wear indicators:Tγ,wear index,material removal,and maximum wear depth,under diverse curves,non-compensated lateral accelerations(A_(nc)),and *** findings showed a correlation of 0.96 between Tγand wear depth and 0.82 between wear index and material removed for the outer *** the results,the Tγis better than the wear index to be used when analyzing wear depth while the wear index is more suited to foresee the material *** results also show the low influence of A_(nc)on wear index and Tγ.By considering these factors together,the study aims to improve the understanding of wheel-rail wear by selecting the best wear analysis approaches based on the effectiveness of each parameter.

关键词： Wear index Wear volume Wear modeling Dynamic simulation

Employing electrochemically derived pH gradients for Lab-on-PCB protein preconcentration devices

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Microsystems & Nanoengineering 2024年第1期10卷 79-87页

作者： Grace Maxted pedro Estrela Despina Moschou Department of Electronic and Electrical Engineering University of BathBath BA27AYUK Centre for Bioengineering and Biomedical Technologies(CBio) University of BathBath BA27AYUK

Protein preconcentration is an essential sample preparation step for analysis in which the targeted proteins exist in low concentrations,such as bodily fluids,water,or ***,very few practical implementations of miniaturized protein preconcentration devices have been demonstrated in practice,and even fewer have been integrated with other microanalytical *** approaches rely heavily on additional chemicals and reagents and introduce complexity to the overall *** this paper,we propose a novel miniaturized isoelectric focusing-based protein preconcentration screening device based on electrochemically derived pH gradients rather than existing chemical reagent *** this way,we reduce the need for additional chemical reagents to zero while enabling device incorporation in a seamlessly integrated full protein analysis microsystem via Lab-on-PCB *** apply our previously presented Lab-on-PCB approach to quantitatively control the pH of a solution in the vicinity of planar electrodes using electrochemical acid generation through redox-active self-assembled *** presented device comprises a printed circuit board with an array of gold electrodes that were functionalized with 4-aminothiophenol;this formed a self-assembled monolayer that was electropolymerized to improve its electrochemical *** preconcentration was performed in two *** first was open and needed the use of a holder to suspend a well of fluid above the electrodes;the second used microfluidic channels to enclose small volumes of *** here are the resulting data for protein preconcentration in both these forms,with a quantitative concentration factor shown for the open form and qualitative proof shown for the microfluidic.

关键词： electrochemical proof qualitative

Conformational dynamics as an intrinsic determinant of prion protein misfolding and neurotoxicity

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Neural Regeneration Research 2024年第10期19卷 2095-2096页

作者： Alessandro Cembran pedro Fernandez-Funez Department of Chemistry and Biochemistry University of Minnesota DuluthDuluthMNUSA Department of Biomedical Sciences University of Minnesota Medical SchoolDuluth CampusDuluthMNUSA

The prion protein(PrP) is the key molecular and pathological mediator of prion diseases,a heterogeneous group of brain disorders with fatal *** diseases are rare but deserve special attention because of their unique f... 详细信息

关键词： folding intrinsic dynamics

Effect of the Coulomb and dielectric forces on the onset of Rayleigh-Bénard convection

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Acta Mechanica Sinica 2024年第6期40卷 64-77页

作者： Zhonglin Du pedro A.Vázquez Jian Wu School of Energy Science and Engineering Harbin Institute of TechnologyHarbin150001China Heilongjiang Key Laboratory of Micro-and Nano-scale Fluid Flow and Heat Transfer Harbin150001China Departamento de Física Aplicada III ETSIIUniversidad de SevillaSevilla41092Spain

In this paper,the effect of Coulomb and dielectric forces on the onset of Rayleigh-Bénard convection(RBC)in a dielectric liquid layer contained between two parallel electrode plates has been numerically *** different operating conditions have been considered in electrohydrodynamic(EHD)conduction:ohmic and saturation,and variations in the physical properties of the dielectric fluid with *** electric equations and the state equations based on the Boussinesq approximation are integrated in the framework of OpenFOAM buoyantBoussinesqPimpleFoam *** results show that in the ohmic regime,the combined effect of Coulomb and dielectric forces promotes the onset of RBC flow,while in the saturation state,the inhibition of RBC flow by Coulomb force is more *** value of the critical Rayleigh number Ra decreases with increasing electric Reynolds number ReE in the ohmic regime,whereas in the saturation state,the critical Ra increases with increasing *** the saturation regime,the flow field always has a steady flow in the range of parameters ***,the onset of the RBC flow promoted by the dielectric force is more pronounced in the ohmic *** to the presence of the dielectric force,the flow field exhibits periodic oscillatory flow at low electric Reynolds numbers for the range of parameters considered.

关键词： EHD conduction Dielectric force Rayleigh-Bénard convection OpenFOAM

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

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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

New pharmacological tools:the use of diterpenes to promote adult hippocampal neurogenesis

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Neural Regeneration Research 2024年第8期19卷 1629-1630页

作者： Ricardo Gomez-Oliva pedro Nunez-Abades Carmen Castro Department of Biomedicine Biotechnology and Public HealthDivision of PhysiologyUniversity of CadizCadizSpain Biomedical Research and Innovation Institute of Cadiz(INiBICA) CadizSpain Department of Physiology University of SevilleSevilleSpain

Tissue regeneration maintains homeostasis and preserves the functional features of each ***,not all tissues show a strong repairing *** is the case of the central nervous *** is now well established that the generation of new functional neurons from stem cells in the adult brain occurs in specific regions of the brain of different species such as rodents,birds,primates,and humans(Eriksson et al.,1998).

关键词： capacity maintain preserve

Physico-chemical characterization of acid base disorders in patients with COVID-19:A cohort study

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World Journal of Nephrology 2024年第2期13卷 16-23页

作者： Sergio Pinto de Souza Juliana R Caldas Marcelo Barreto Lopes Marcelo augusto Duarte Silveira Fernanda Oliveira Coelho Igor Oliveira Queiroz pedro Domingues Cury Rogério da Hora Passos Department of Nephrology Hospital São RafaelSalvadorBA 41253190Brazil Department of Nephrology D’Or Institute for Research and Education(IDOR)SalvadorBA 41253190Brazil Faculty of Medicine Escola Bahiana de Medicina e Saúde Pública-EBMSPSalvadorBA 40290000Brazil Department of Intensive Care D’Or Institute for Research and Education(IDOR)SalvadorBA 41253190Brazil Hospital São Rafael D’Or Institute for Research and Education(IDOR)SalvadorBA 41253190Brazil Department of Intensive Care Unit Hospital Israelita Albert EinsteinSao PauloSP 05652900Brazil

BACKGROUND Acid-base imbalance has been poorly described in patients with coronavirus disease 2019(COVID-19).Study by the quantitative acid-base approach may be able to account for minor changes in ion distribution that may have been over-looked using traditional acid-base analysis *** a cohort of critically ill COVID-19 patients,we looked for an association between metabolic acidosis surrogates and worse clinical outcomes,such as mortality,renal dialysis,and length of hospital *** To describe the acid-base disorders of critically ill COVID-19 patients using Stewart’s approach,associating its variables with poor *** This study pertained to a retrospective cohort comprised of adult patients who experienced an intensive care unit stay exceeding 4 days and who were diagnosed with severe acute respiratory syndrome coronavirus 2 infection through a positive polymerase chain reaction analysis of a nasal swab and typical pulmonary involvement observed in chest computed tomography *** and clinical data were obtained from electronic *** variables were compared using Fisher’s exact *** data were presented as median and interquartile *** Mann-Whitney U test was used for *** In total,211 patients were *** mortality rate was 13.7%.Overall,149 patients(70.6%)presented with alkalosis,28 patients(13.3%)had acidosis,and the remaining 34 patients(16.2%)had a normal arterial pondus *** those presenting with acidosis,most had a low apparent strong ion difference(SID)(20 patients,9.5%).Within the group with alkalosis,128 patients(61.0%)had respiratory *** non-survivors were older,had more comorbidities,and had higher Charlson’s and simplified acute physiology score *** did not find severe acid-base imbalance in this *** analyzed Stewart’s variables(effective SID,apparent SID,and strong ion gap and the effect of albumin,lactate,phosphorus,and chloride)were not d

关键词： COVID-19 Physicochemical approach Acid-base status Critically ill patients Acute respiratory syndrome

Targeting epidermal growth factor receptor signaling to facilitate cortical injury repair?

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Neural Regeneration Research 2024年第5期19卷 935-936页

作者： Ricardo Gómez-Oliva pedro Nunez-Abades Carmen Castro Área de Fisiología Facultad de Medicina Universidad de CádizCadizSpain Instituto de Investigación e Innovación en Biomedicina de Cádiz CadizSpain Departamento de Fisiología Facultad de FarmaciaUniversidad de SevillaSevilleSpain

The existence of neural stem cells(NSC)in specific areas of the adult mammalian brain leads to the generation of new neurons involved in homeostatic *** is the case of the NSC of the subventricular zone(SVZ)that produces olfactory bulb(OB)*** neurons integrate into circuits to modulate sensory information and participate in olfactory processing(Bragado Alonso et al.,2019).A series of hierarchical events need to take place to produce OB neurons from NSC of the ***,the activation of quiescent NSC is necessary to produce intermediate transit amplifying progenitors(TAP),which will generate *** latter are cells that maintain a proliferative phenotype while in an immature ***,once they initiate migration toward the OB,they progressively undergo their differentiation into neurons(Kjell et al.,2020).

关键词： ventricular maintain

Percutaneous decannulation of extracorporeal membrane oxygenation using MANTA device:A real-world single-center experience

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World Journal of Cardiology 2024年第10期16卷 574-579页

作者： Ioannis Milioglou Alice Qian pedro Rafael Vieira de Oliveira Salerno Gabriel Tensol Rodrigues Pereira Luis augusto Palma Dallan Kelsey E Gray Michael Morrison Yasir Abu-Omar Mohammad Eldiasty Cristian Baeza Department of Cardiology University Hospitals Cleveland Medical CenterClevelandOH 44106United States Department of Surgery University Hospitals Cleveland Medical Center and Case Western Reserve University School of MedicineClevelandOH 44106United States

BACKGROUND The MANTA vascular closure device(VCD)represents a novel approach to achieving hemostasis after large-bore femoral access *** clinical studies have evaluated the efficacy of the MANTA device across a range of patient populations undergoing different ***,there is still a paucity of data available concerning the use of MANTA devices in aiding the decannulation of venoarterial extracorporeal membrane oxygenation(VAECMO).AIM To present our single-center experience of utilizing the MANTA VCD in patients undergoing this *** This single-center study included all patients undergoing percutaneous decannulation of femoral VA-ECMO using the MANTA plug-based VCD between January 2021 and October 2023 at University Hospitals Cleveland Medical *** criteria were adult patients who required prolonged(>24 hours)hemodynamic support with *** included all-cause mortality,hemostasis,bleeding,limb ischemia,and site *** This is a retrospective cohort study of 19 patients with a mean age of 56.8 *** of them were males with a mean body mass index of *** most common extracorporeal membrane oxygenation indication was acute coronary syndrome complicated by cardiogenic shock at 36.8%.The mean length of intensive care unit stay for these patients was 18.8±8.42 *** out of 19 patients survived to *** MANTA device was successfully deployed in 19 patients,with 10 procedures conducted at the bedside and 9 in an operating room *** hemostasis was achieved within 5 minutes of MANTA deployment in 17 out of 19 *** 2 patients manual compression after Manta deployment was required to achieve adequate ***,acute lower extremity ischemia was noted in two patients,necessitating endovascular *** infections were reported at the site of MANTA *** Overall,based on our experience and that of other centers,the MANTA VCD

关键词： Extracorporeal membrane oxygenation MANTA Decannulation Hemostasis Ischemia