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On the numerical solution to the truncated discrete SPH formulation of the hydrostatic problem

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Journal of Hydrodynamics 2020年第4期32卷 699-709页

作者： Pablo Eleazar Merino-Alonso fabricio Macia Antonio Souto-Iglesias Mathematical Modeling Analysisand Simulation Applied to Engineering Research Group(M2ASAI)Universi dad politecnica de Madrid(UPM)School of marine engineering(ETSIN)MadridSpain Marine and Hydrodynamical Model Basin Research Group(CEHINAV) Universidad Politecnica de Madrid(UPM)School of Marine Engineering(ETSIN)MadridSpain

The aim of this work is to study the solution of the smoothed particle hydrodynamics(SPH)discrete formulation of the hydrostatic problem with a free *** problem,in which no time dependency is considered,takes the form of a system of linear *** particular,the problem in one dimension is *** focus is set on the convergence when both the particle spacing and the smoothing length tend to zero by keeping constant their *** of this ratio of the order of one,corresponding to a limited number of neighbors,are of practical ***,the problem in which each particle has one single neighbor at each side is *** explicit expressions of the numerical solution and the quadratic error are provided in this *** expression of the quadratic error demonstrates that the SPH solution does not converge to the exact one in general under the specified *** this case,the error converges to a residue,which is in general large compared to the norm of the exact *** cases with two and three neighbors are also *** analytical study in the case of two neighbors is performed,showing how the kernel influences the accuracy of the solution through modifying the condition number of the referred system of linear *** addition to that,a numerical investigation is carried out using several Wendland kernel *** two and three neighbors are involved it is found that the error tends in most cases to a small limiting value,different from zero,while divergent solutions are also found in the case of two neighbors with the Wendland Kernel *** cases with more neighbors are also *** general,the Wendland Kernel C2 turns out to be the worst choice,as the solution is divergent for certain values of the ratio between the particle spacing and the smoothing length,associated with an ill-conditioned matrix.

关键词： Smoothed particle hydrodynamics(SPH) convergence water-at-rest problem hydrostatic tank,free surface kernel truncation

Alpha2-adrenergic receptor activation reinstates motor deficits in rats recovering from cortical injury

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Neural Regeneration Research 2023年第4期18卷 875-880页

作者： Gabriela García-díaz Laura ERamos-Languren Carmen Parra-cid Joel Lomelí Sergio Montes Camilo Ríos Antonio Bueno-Nava Ignacio Valencia-Hernández Rigoberto González-Piña department of Pharmacology Section of Postgraduate Studies and ResearchHigh Medical SchoolInstituto Politécnico NacionalSalvador Díaz MirónAlcaldía Miguel HidalgoMexico CityMexico department of Neurobiology of Aging and Brain damage Coordination of Psychobiology and NeurosciencesFaculty of PsychologyNational Autonomous University of MexicoAv.Universidad 3040Col.Copilco UniversidadAlcaldía CoyoacánMexico CityMexico direction of Research National Institute of Rehabilitation LGIICalz.Mexico-Xochimilco 289Col.Arenal de GuadalupeAlcaldía TlalpanMexico CityMexico department of Pharmacology Multidisciplinary Academic Unit Reynosa-Aztlan ReynosaAutonomous University of Tamaulipascalle 16 y lago de ChapalaCol.AztlánTamaulipasMexico department of Neurochemistry National Institute of Neurology and Neurosurgery MVSAv.Insurgentes Sur 3877Col.La FamaAlcaldia TlalpanMexico CityMexico department of Special Education University of the AmericasPuebla 223Col.RomaAlcaldía CuauhtémocMexico CityMexico

Norepinephrine plays an important role in motor functional recovery after a brain injury caused by ferrous *** of norepinephrine release by clonidine is correlated with motor deficits after motor cortex *** aim of this study was to analyze the role ofα-adrenergic receptors in the restoration of motor deficits in recovering rats after brain *** rats were randomly assigned to the sham and injury groups and then treated with the following pharmacological agents at 3 hours before and 8 hours,3 days,and 20 days after ferrous chloride-induced cortical injury:saline,clonidine,efaroxan(a selective antagonist ofα-adrenergic receptors)and clonidine+*** sensorimotor score,the immunohistochemical staining forα-adrenergic receptors,and norepinephrine levels were *** hours post-injury,the sensorimotor score and norepinephrine levels in the locus coeruleus of the injured rats decreased,and these effects were maintained 3 days ***,20 days later,clonidine administration diminished norepinephrine levels in the pons compared with the sham *** effect was accompanied by sensorimotor *** effects were blocked by *** conclusion,an increase inα-adrenergic receptor levels was observed after *** restores motor deficits in rats recovering from cortical injury,an effect that was prevented by *** underlying mechanisms involve the stimulation of hypersensitiveα-adrenergic receptors and inhibition of norepinephrine activity in the locus *** results of this study suggest thatαreceptor agonists might restore deficits or impede rehabilitation in patients with brain injury,and therefore pharmacological therapies need to be prescribed cautiously to these patients.

关键词： alpha2-adrenoceptors ambulatory behavior clonidine cortical injury efaroxan functional recovery immunohistochemistry motor deficit norepinephrine sensorimotor score

YbF_3/SiO_2 Fillers as Radiopacifiers in a dental Adhesive Resin

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Nano-Micro Letters 2012年第3期4卷 189-196页

作者： Neftali L.V.Carreno Thiago C.S.Oliveira Evandro Piva Fernanda B.Leal Giana S.Lima Marcelo d.Moncks Cristiane W.Raubach fabricio A.Ogliari Technology development Center Engineering of MaterialFederal University of Pelotas Biomaterials development and Control Center School of DentistryFederal University of Pelotas department of Analytical and Inorganic Chemistry IQGFederal University of Pelotas

The objective of this study was to evaluate the effect of functionalizing a dental adhesive resin with YbF_3/SiO_2 fillers for use as *** of YbF_3/SiO_2 were obtained with the high-energy mechanical milling method and characterized by both physical and chemical *** characterization,the particles were sieved and silanized prior to being incorporated into an adhesive *** stability of the particle suspension was then *** light activation,the radiopacity,degree of conversion,flexural strength and elastic modulus were *** dental adhesive resins with 10 and 15 wt% of filler provided satisfactory radiopacity,while flexural strength and elastic modulus were not *** degree of conversion was statistically lower than that of the control(pd used for incorporating the tested ytterbium fluoride/silicon dioxide particles at concentrations of 10 and 15 wt% was shown to be feasible for the development of a radiopaque dental adhesive system.

关键词： Radiopacifier YbF3/SiO2 dental adhesive resin Composite

旋转输运速度场积分SPH对流扩散方程解的收敛性

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Acta Mechanica Sinica 2023年第2期39卷 61-70页

作者： Pablo Eleazar Merino-Alonso fabricio Macià Antonio Souto-Iglesias departamento de Arquitectura Constructión y Sistemas Oceánicos y NovalesUniversidad Politécnica de MadridMadridSpain departamento de Matemática e Informática Aplicadas a las Ingenierías Civil y Naval Universidad Politécnica de MadridMadridSpain

本文在刚性旋转输运速度场的特殊情况下,建立了二维平流扩散方程的积分光滑粒子流体动力学(SPH)解的收敛性.考虑了Morris等人对拉普拉斯算子的近似,在傅里叶空间中建立了SPH解与精确解的收敛性.证明了如果满足核的傅里叶变换的某个条件... 详细信息

本文在刚性旋转输运速度场的特殊情况下,建立了二维平流扩散方程的积分光滑粒子流体动力学(SPH)解的收敛性.考虑了Morris等人对拉普拉斯算子的近似,在傅里叶空间中建立了SPH解与精确解的收敛性.证明了如果满足核的傅里叶变换的某个条件,即我们称之为正条件,则收敛是有保证的.这个条件是核的傅里叶变换其径向轮廓的一阶矩为正,并通过数值验证说明了分析结果.根据L2范数和最大范数,比较了使用不同核包括SPH社区更常用的核(即Wendland核以及三次和线性样条核)获得的数值解.除此之外,提出并测试了一个病理核,该核不满足正条件,导致了非收敛结果.这一事实表明,在对流扩散方程的情况下,正条件不仅是收敛的充分条件,也是必要条件.

关键词： Smoothed particle hydrodynamics Numerical analysis diffusion Convergence Fourier analysis

A 3d Bioprinted Gut Anaerobic Model for Studying Bacteria–Host Interactions

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Research 2023年第3期6卷 697-710页

作者： Liqin Cheng Tingting Liu Qiong Liu Liming Lian Guosheng Tang Luis Santiago Mille fabricio Romero García Lars Engstrand Yu Shrike Zhang Juan du Centre for Translational Microbiome Research(CTMR) Department of MicrobiologyTumorand Cell BiologyKarolinska InstitutetStockholmSweden division of Engineering in Medicine Department of MedicineBrigham and Women’s HospitalHarvard Medical School65 Landsdowne StreetCambridgeMA 02139USA Science for Life Laboratory StockholmSweden

The role of the human intestinal tract in host–microbe interactions has been highlighted in recent *** 3-dimensional(3d)models have been developed to reproduce the physiological characteristics of the human gut and to investigate the function of the gut *** challenge for 3d models is to recapitulate the low oxygen concentrations in the intestinal ***,most earlier 3d culture systems used a membrane to physically separate bacteria from the intestinal epithelium,which has sometimes made the studies of bacteria adhering to or invading cells less *** report the establishment of a 3d gut epithelium model and cultured it at high cell viability under an anaerobic *** further cocultured intestinal bacteria including both commensal and pathogen directly with epithelial cells in the established 3d model under the anaerobic *** subsequently compared the gene expression differences of aerobic and anaerobic conditions for cell and bacterial growth via dual RNA *** study provides a physiologically relevant 3d gut epithelium model that mimics the anaerobic condition in the intestinal lumen and supplies a powerful system for future in-depth gut–microbe interactional investigations.

关键词： epithelium Host Bacteria

Single atom Cu-N-C catalysts for the electro-reduction of CO_(2) to CO assessed by rotating ring-disc electrode

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Journal of Energy Chemistry 2024年第1期88卷 169-182,I0004页

作者： S.Pérez-Rodríguez M.Gutiérrez-Roa C.Giménez-Rubio d.Ríos-Ruiz P.Arévalo-cid M.V.Martínez-Huerta A.Zitolo M.J.Lázaro d.Sebastián Instituto de Carboquímica(CSIC) Miguel Luesma Castán 450018 ZaragozaSpain Instituto de Catálisis y Petroleoquímica(CSIC) Marie Curie 228049 MadridSpain Synchrotron SOLEIL L’Orme des MerisiersDépartementale 12891190France

The electrochemical CO_(2) reduction reaction(CO_(2)RR) to controllable chemicals is considered as a promising pathway to store intermittent renewable energy. Herein, a set of catalysts based on copper-nitrogendoped carbon xerogel(Cu-N-C) are successfully developed varying the copper amount and the nature of the copper precursor, for the efficient CO_(2)RR. The electrocatalytic performance of Cu-N-C materials is assessed by a rotating ring-disc electrode(RRdE), technique still rarely explored for CO_(2)RR. For comparison, products are also characterized by online gas chromatography in a H-cell. The as-synthesized Cu-NC catalysts are found to be active and highly CO selective at low overpotentials(from -0.6 to -0.8 V ***) in 0.1 M KHCO_(3), while H_(2) from the competitive water reduction appears at larger overpotentials(-0.9 V vs. RHE). The optimum copper acetate-derived catalyst containing Cu-N_(4) moieties exhibits a CO_(2)-to-CO turnover frequency of 997 h^(-1) at -0.9 V vs. RHE with a H_(2)/CO ratio of 1.8. These results demonstrate that RRdE configuration can be used as a feasible approach for identifying electrolysis products from CO_(2)RR.

关键词： Cu-N-C Carbon xerogel Rotating ring disc electrode Carbon dioxide reduction reaction Carbon monoxide

ThMn12-Type Alloys for Permanent Magnets

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Engineering 2020年第2期6卷 141-147页

作者： G.C.Hadjipanayis A.M.Gabay A.M.Schonhobel A.Martin-cid J.M.Barandiaran d.Niarchos department of Physics and Astronomy University of DelawareNewarkDE 19716USA BCMaterials Leioa 48940Spain NCSR demokritos Agia Paraskevi 15341Greece

Iron-rich compounds with the tetragonal ThMn12-type structure have the potential to meet current demands for rare-earth-lean permanent magnets with high energy density and operating temperatures of 150-200℃.However,while it is normal for magnet technology to lag behind the development of underlying magnetic material,this gap has always been unusually large for ThMn12-type *** gap has widened further in recent years,as excellent combinations of intrinsic magnetic properties have been obtained in compounds synthesized with a smaller amount of structure-stabilizing elements(e.g.,SmFe11V or Sm0.8Zr0.2Fe9.2Co2.3Ti0.5)or with no such elements(i.e.,SmFe9.6Co2.4 thin films).The search for promising compounds continues-with increasing help coming from theoretical ***,progress in the development of magnets beyond polymer-bonded interstitially modified powders remains *** introduction of lanthanum(La)was found to stabilize low-meltingtemperature minority phases in Sm(Fe,Ti)12 alloys,thus allowing for liquid-phase sintering for the first *** high reactivity of La,however,has apparently undermined the development of coercivity(Hc).A controlled crystallization of the initially suppressed ThMn12-type phase makes"bulk"magnetic hardening possible,not only in Sm-Fe-V alloys(in which it has been known since the 1990s),but also is in La-added(Ce,Sm)(Fe,Ti)12 *** properties of the bulk-hardened alloys,however,remain *** synthesized(Sm,Zr)(Fe,Si)12 and(Sm,Zr)(Fe,Co,Ti)12 powders may become suitable for sintering into powerful fully dense magnets,although not before a higher degree of anisotropy in both alloys and a higher Hc in the latter alloy have been developed.

关键词： Permanent magnets Rare earths permanent magnets ThMn12 structure

非裔厄瓜多尔文学中的黑人性——对阿达贝托·奥尔蒂斯小说《朱云戈》的批判性跨文化分析

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非裔厄瓜多尔文学中的黑人性——对阿达贝托·奥尔蒂斯小说《朱云...

作者： Licoa Campos Adolfo fabricio 上海外国语大学

学位级别：硕士

阿达伯托·奥尔蒂斯是厄瓜多尔最伟大的作家之一,他的作品也是拉丁美洲非裔西班牙文学的杰出代表。作为黑白混血儿,他在两种文化和身份之间成长,切身体会了种族主义和阶级歧视。在写作中,他重现了厄瓜多尔的黑人性及其演变,特别是他的... 详细信息

阿达伯托·奥尔蒂斯是厄瓜多尔最伟大的作家之一,他的作品也是拉丁美洲非裔西班牙文学的杰出代表。作为黑白混血儿,他在两种文化和身份之间成长,切身体会了种族主义和阶级歧视。在写作中,他重现了厄瓜多尔的黑人性及其演变,特别是他的小说《朱云戈》。该小说获得了1942年厄瓜多尔“国家最佳小说奖”,讲述了大约三十年来非裔厄瓜多尔人的生活以及其与不同种族的关系。本文运用跨文化交际批评理论,分析了小说《朱云戈》中的权力关系如何影响跨文化交流以及非裔厄瓜多尔黑人性的建构、觉醒和解读。基于此,本文提出厄瓜多尔黑人性是一个长期的文化适应、转型和丰富的过程,是跨文化接触受到权力的种族、政治和社会结构影响的结果。本文还认为,权力差异导致了从属关系、种族歧视和社会不公,厄瓜多尔黑人性是对此的一种抵制。该论文得出的结论是,厄瓜多尔黑人性是一种极为复杂的文化建构,它来自受权力结构影响的跨文化人际交往中,原始非洲文化被修改的过程。最后本论文认为,非裔厄瓜多尔人通过保护非洲遗产,珍重并维护了他们的黑人性。

关键词：厄瓜多尔文学中的黑人性流散非州性阿达伯托·奥尔蒂斯《朱云戈》跨文化交际批评

Three-dimensional imaging of the uterus:The value of the coronal plane

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World Journal of Radiology 2015年第12期7卷 484-493页

作者： Lufee Wong Nikki White Jayshree Ramkrishna Edward Araujo Júnior Simon Meagher fabricio da Silva Costa Monash Ultrasound for Women department of Obstetrics and Gynaecology Monash Medical CentreSouthern Health department of Obstetrics Paulista School of Medicine-Federal University of Sao Paulo(EPM-UNIFESP)

Advent in three-dimensional(3d) imaging technology has seen 3d ultrasound establish itself as a useful adjunct complementary to traditional two-dimensional imaging of the female pelvis. This advantage largely arises from its ability to reconstruct the coronal plane of the uterus, which allows further delineation of many gynecological disorders. 3d imaging of the uterus is now the preferred imaging modality for assessing congenital uterine anomalies and intrauterine device localization. Newer indications include the diagnosis of adenomyosis. It can also add invaluable information to delineate other endometrial and myometrial pathology such as fibroids and endometrial polyps.

关键词： Three-dimensional ultrasound Coronal view Pelvis Uterus Uterine anomalies