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The analysis of composite laminated beams using a 2D interpolating meshless technique

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Acta mechanica sinica 2018年第1期34卷 99-116页

作者： s.H.m.sadek J.Belinha m.P.L.Parente R.m.Natal jorge J.m.A.César de sá A.J.m.Ferreira Department of mechanical Engineering Faculty of EngineeringUniversity of Porto Institute of mechanical Engineering and Industrial management University of Porto

Laminated composite materials are widely implemented in several engineering constructions. For its relative light weight, these materials are suitable for aerospace, military, marine, and automotive structural applications. To obtain safe and economical structures, the modelling analysis accuracy is highly relevant. since meshless methods in the recent years achieved a remarkable progress in computational mechanics, the present work uses one of the most flexible and stable interpolation meshless technique available in the literature—the Radial Point Interpolation method(RPIm).Here, a 2 D approach is considered to numerically analyse composite laminated beams. Both the meshless formulation and the equilibrium equations ruling the studied physical phenomenon are presented with detail. several benchmark beam examples are studied and the results are compared with exact solutions available in the literature and the results obtained from a commercial finite element software. The results show the efficiency and accuracy of the proposed numeric technique.

关键词： Radial point interpolators RPIm Laminated beam meshless method

A Review of Recent Advances in Hybrid Natural Fiber Reinforced Polymer Composites

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Journal of Renewable materials 2022年第3期10卷 561-589页

作者： jorge Neto Henrique Queiroz Ricardo Aguiar Rosemere Lima Daniel Cavalcanti mariana Doina Banea Federal Centre of Technological Education in Rio de Janeiro(CEFET/RJ) Rio de JaneiroBrazil

Natural fiber reinforced polymer composites(NFRCs)have demonstrated great potential for many different applications in various industries due to their advantages compared to synthetic fiber-reinforced composites,such as low environmental impact and low ***,one of the drawbacks is that the NFRCs present relatively low mechanical properties and the absorption of humidity due to the hydrophilic characteristic of the natural *** method to increase their performance is ***,understanding the properties and potential of using multiple reinforcement’s materials to develop hybrid composites is of great *** paper provides an overview of the recent advances in hybrid natural fiber reinforced polymer ***,the main factors that affect the performance of hybrid fiber-reinforced composites were briefly *** effect of hybridization on the mechanical and thermal properties of hybrid composites reinforced with several types of natural fibers(i.e.,sisal,jute,curauá,ramie,banana,etc.)or natural fibers combined with synthetic fibers is ***,the water absorption behaviour of hybrid fiber-reinforced composites is also *** was con-cluded that the main challenges that need to be addressed in order to increase the use of natural-natural or natural-synthetic hybrid composites in industry are the poor adhesion between natural fibers and matrix,thermal stability and moisture absorption of natural *** of these challenges were addressed by recent develop-ment in fibers treatment and modification,and product innovation(hybridization).

关键词： Natural fiber composites(NFC) hybrid composites mechanical properties thermal properties water absorption

Editorial:metabolomics in chronic hepatitis C:Decoding fibrosis grading and underlying pathways

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World Journal of Hepatology 2023年第11期15卷 1170-1173页

作者： jorge Quarleri m Victoria Delpino Instituto de Investigaciones Biomédicas en Retrovirus y sida Universidad de Buenos AiresConsejo Nacional de Investigaciones Científicas y TécnicasBuenos Aires 1121Argentina

In the management of the growing population of hepatitis C virus-infected patients,a significant clinical challenge exists in determining the most effective methods for assessing liver *** prognosis and treatment of chronic hepatitis C depend,in part,on the evaluation of histological activity,specifically cell necrosis and inflammation,and the extent of liver *** parameters are traditionally obtained through a liver ***,liver biopsy presents both invasiveness and potential sampling errors,primarily due to inadequate biopsy *** circumvent these issues,several non-invasive markers have been proposed as alternatives for diagnosing liver *** imaging techniques and blood parameters as single markers or combined with clinical information are *** Editorial discusses the identification of a set of six distinctive lipid metabolites in every fibrosis grade that appear to show a pronounced propensity to create clusters among patients who share the same fibrosis grade,thereby demonstrating enhanced efficacy in distinguishing between the different grades.

关键词： Hepatitis C virus Chronic hepatitis C Liver fibrosis Biomarker Liquid biopsy

sACI Protocol: Preliminary Guidelines for the Development of Digital Health Technologies for Clinical Trials in Brazil

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E-Health Telecommunication systems and Networks 2022年第3期11卷 85-100页

作者： Lídia maria Lourençön Rodrigues Agia jorge Luiz Dias Agia Rui Pedro Charters Lopes Rijo Valdes Roberto Bollela Domingos alves Department of social medicine Ribeir&#227 o Preto medical school University of S&#227 o Paulo Ribeir&#227 o Preto Brazil Postgraduate Program in Production Engineering UNIP S&#227 o Paulo Brazil Polytechnic Institute of Leiria Leiria Portugal Department of Internal medicine Ribeir&#227 o Preto medical school University of S&#227 o Paulo Ribeir&#227 o Preto Brazil

In the last decade, evidence-based medical practice has been supported on a large scale by computerized decision support tools, aiming to reduce diagnostic and therapeutic uncertainty, complementing the actions of the health professional. With technological developments, it is now possible to consider these systems as part of clinical intervention, both for the diagnosis and treatment of diseases. The literature has described the implementation of e-health tools, that is, technological innovations in the health area such as software, applications, serious games, among others, as a strategy to improve the process and adherence to treatment. However, there is still no standardized instrument in Brazil that can be used to guide the development, from the research phase, and the implementation of these tools as a health intervention, also impacting patient outcomes. With the objective of investigating a new therapeutic and preventive form, based on intervention with a computerized system, this work proposes the creation of guidelines for the registration and implementation of e-health tools as a clinical intervention. The proposal aims to be able to assist in the reporting standardization from the development stage to the application of the e-health tool helping in the treatment of diseases, registering all the experience lived in the research and applying it in different contexts of health.

关键词： Reporting Guidelines Clinical Trials Digital Health E-Health

Non-pharmacological cognitive intervention for aging and dementia:Current perspectives

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World Journal of Clinical Cases 2013年第8期1卷 233-241页

作者： jorge alves Rosana magalh?es álvaro machado óscar F gon?alves Adriana sampaio Agavni Petrosyan Neuropsychophysiology Lab CIPsiSchool of PsychologyUniversity of Minho4710-057BragaPortugal Department of Neurology Hospital de Braga4710-243 BragaPortugal Department of Counseling and Applied Educational Psychology Bouvé College of Health SciencesNortheastern UniversityBostonMA 02115United States Department of Cognitive sciences University of California at IrvineIrvineCA 92717United States

In recent years, cognitive difficulties associated with normal aging and dementia have been receiving increased attention from both public and scientific communities. With an increase in overall lifespan, promoting healthy cognition has become a priority and a necessity for minimizing and preventing individual and societal burdens associated with cognitive dysfunctions in the elderly. The general awareness concerning the efficacy of preventive(e.g., lifestyles) and palliative treatment strategies of cognitive impairments, related to either healthy or unhealthy trajectories in cognitive aging, is continuously rising. There are several therapeutic strategies which can be broadly classified as either pharmacological or non-pharmacological/psychosocial. In face of the modest evidence for success of pharmacological treatments, especially for dementia related impairments, psychosocial interventions are progressively considered as a complementary treatment. Despite the relative spread of psychosocial interventions in clinical settings, research in this area is rather scarce with evidence for success of these therapies remaining controversial. In this work we provide an evidence based perspective on cognitive intervention(s) for healthy aging, pre-dementia(mild cognitive impairment), and dementia populations. Current evidence and future directions for improving cognitive functions in the elderly are discussed as well.

关键词： Dementia Aging Cognitive intervention Cognition Non-pharmacological therapies

Are the mechanisms involved in astrocyte and lymphocyte death during HIV infection similar?

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Neural Regeneration Research 2019年第10期14卷 1707-1708页

作者： Diego s. Ojeda Andreas Till jorge Quarleri Instituto de Investigaciones Biomedicas en Retrovirus y sIDA (INBIRs) Universidad de Buenos Aires-CONICETArgentina Institute of Reconstructive Neurobiology Life & Brain CenterUniversity of BonnBonnGermany

Acquired immune deficiency syndrome is associated with the death of CD4+ T lymphocytes. The entry of the human immunodeficiency virus (HIV) into the central nervous system leads to a broad spectrum of HIV-associated neurocognitive disorders (HAND) ranging from mild to severe dementia. Inside the central nervous system, HIV establishes infection in astrocytes - the predominant cell type in the brain, thus causing neuropathology, but the underlying mechanisms remain unknown.

关键词： Acquired immune broad spectrum remain unknown

A model for strong attenuation and dispersion of seismic P-waves in a partially saturated fractured reservoir

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science China(Physics,mechanics & Astronomy) 2010年第8期53卷 1383-1387页

作者： BRAJANOVsKI miroslav müLLER Tobias m PARRA jorge O Department of Exploration Geophysics Curtin University of Technology Geophysical Institute University of Karlsruhe southwest Research Institute

In this work we interpret the data showing unusually strong velocity dispersion of P-waves (up to 30%) and attenuation in a relatively narrow frequency range. The cross-hole and VsP data were measured in a reservoir, which is in the porous zone of the silurian Kankakee Limestone Formation formed by vertical fractures within a porous matrix saturated by oil, and gas patches. such a medium exhibits significant attenuation due to wave-induced fluid flow across the interfaces between different types of inclusions (fractures, fluid patches) and background. Other models of intrinsic attenuation (in particular squirt flow models) cannot explain the amount of observed dispersion when using realistic rock properties. In order to interpret data in a satisfactory way we develop a superposition model for fractured porous rocks accounting also for the patchy saturation effect.

关键词： attenuation dispersion Biot’s slow wave poroelasticity fractures patchy-saturation

Food allergy among mexican infants and preschoolers:prevalence and associated factors

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World Journal of Pediatrics 2023年第4期19卷 401-405页

作者： martín Bedolla-Barajas Jaime morales-Romero Rafael sánchez-magallón jorge Alejandro Valdez-soto Tonatiuh Ramses Bedolla-Pulido Carlos meza-López Allergy and Immunology Department Nuevo Hospital Civil de Guadalajara Dr.Juan I.MenchacaSalvador Quevedo y Zubieta No.740Colonia La Perla44340GuadalajaraJaliscoMéxico Institute of Public Health Universidad VeracruzanaXalapaMexico Pediatrics Department Nuevo Hospital Civil de Guadalajara Dr.Juan I.MenchacaGuadalajaraMexico

The number of people with food allergy(FA)has increased in recent decades,as has the number of foods to which they are *** of FA prevalence vary widely,likely because of different definitions,evaluated foods and geo-graphic *** developed countries,overall preva-lence estimates range from 1.9%to 7.2%[1,2].In Latin America,the prevalence of FA in children is between 1.4%and 5.3%[3-6],with important age-based variations(from 1.9%in infants to 0.4%in preschoolers)[7].FA is a complex trait in which the interplay of genetic and environmental fac-tors results in disease ***-known factors that increase atopic susceptibility include sex[8,9],age[10],and socioeconomic status[11-13].Furthermore,the asso-ciation between family history of allergies and childhood FA has been consistently reported in recent ***,a maternal history of allergic disease appears to be more strongly associated with FA than paternal history of atopy[14].

关键词： prevalence allergy allergic

A realistic topological p-n junction at the Bi2se3 （0001） surface based on planar twin boundary defects

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Nano Research 2017年第5期10卷 1784-1793页

作者： Hugo Aramberri m. Carmen munoz jorge I. Cerda Instituto de Ciencia de materiales de madrid (ICmm-CsIC) Cantoblanco Madrid 28049 Spain

We propose a realistic topological p-n junction （TPNJ） by matching two Bi2se3 （0001） slabs with opposite arrangements of planar twin boundary defects. The atomistic modeling of such a device leads to dislocation defects in the hexagonal lattice in several quintuple layers. Nevertheless, total energy calculations reveal that the interface relaxes, yielding a smooth geometrical transition that preserves the nearest-neighbors fcc-type geometry throughout these defect layers. The electronic, magnetic, and transport properties of the junction have then been calculated at the ab initio level under open boundary conditions, i.e., employing a thin-film geometry that is infinite along the electron transport direction. Indeed, a p-n junction is obtained with a built-in potential as large as 350 meV. The calculations further reveal the spin texture across the interface with unprecedented detail. As the main result, we obtain non-negligible transmission probabilities around the F point, which involve an electron spin-flip process while crossing the interface.

关键词： topological insulators p-n junctions spintronics electronic devices twin boundaries