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Design multifunctional Mg–Zr coatings regulating Mg alloy bioabsorption

Journal of Magnesium and Alloys 2024年第4期12卷 1461-1478页

作者： Zohra Benzarti Sandesh Itani JoséDavid Castro Sandra Carvalho ana Sofia ramos University of Coimbra CEMMPREARISEDepartment of Mechanical EngineeringRua Luís Reis Santos3030-788CoimbraPortugal Laboratory of Multifunctional Materials and Applications(LaMMA) Department of PhysicsFaculty of Sciences of SfaxUniversity of SfaxSoukra Road km 3.5B.P.1171Sfax3000Tunisia

Magnesium(Mg)alloys are widely used for temporary bone implants due to their favorable biodegradability,cytocompatibility,hemocompatibility,and close mechanical properties to bone.However,rapid degradation and inadequate strength limit their applicability.To overcome this,the direct current magnetron sputtering technique is employed for surface coating in Mg-based alloys using various zirconium(Zr)content.This approach presents a promising strategy for simultaneously improving corrosion resistance,maintaining biocompatibility,and enhancing strength without compromising osseointegration.By leveraging Mg’s inherent biodegradability,it has the potential to minimize the need for secondary surgeries,thereby reducing costs and resources.This paper is a systematic study aimed at understanding the corrosion mechanisms of Mg–Zr coatings,denoted Mg-xZr(x=0–5 at.%).Zr-doped coatings exhibited columnar growth leading to denser and refined structures with increasing Zr content.XRD analysis confirmed the presence of the Mg(00.2)basal plane,shifting towards higher angles(1.15°)with 5 at.%Zr doping due to lattice parameter changes(i.e.,decrease and increase of“c”and“a”lattice parameters,respectively).Mg–Zr coatings exhibited“liquidphilic”behavior,while Young’s modulus retained a steady value around 80 GPa across all samples.However,the hardness has significantly improved across all samples’coating,reaching the highest value of(2.2±0.3)GPa for 5 at.%Zr.Electrochemical testing in simulated body fluid(SBF)at 37℃ revealed a significant enhancement in corrosion resistance for Mg–Zr coatings containing 1.0–3.4 at.%Zr.Compared with the 5 at.%Zr coating which exhibited a corrosion rate of 32 mm/year,these coatings displayed lower corrosion rates,ranging from 1 to 12 mm/year.This synergistic enhancement in mechanical properties and corrosion resistance,achieved with 2.0–3.4 at.%Zr,suggests potential ability for reducing stress shielding and controlled degradation performance,and consequently,promising functional biodegradable materials f

关键词： Mg-Zr coatings Magnetron sputtering Nanoindentation Corrosion resistance Bone implants

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Colorectal cancer screening:A review of current knowledge and progress in research

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World Journal of Gastrointestinal Oncology 2024年第4期16卷 1119-1133页

作者： Sara ramos Lopes Claudio Martins Inês Costa Santos Madalena Teixeira Élia Gamito ana Luisa Alves Department of Gastroenterology Centro Hospitalar de SetúbalSetúbal 2910-446Portugal

Colorectal cancer(CRC)is one of the most prevalent malignancies worldwide,being the third most commonly diagnosed malignancy and the second leading cause of cancer-related deaths globally.Despite the progress in screening,early diagnosis,and treatment,approximately 20%-25%of CRC patients still present with metastatic disease at the time of their initial diagnosis.Furthermore,the burden of disease is still expected to increase,especially in individuals younger than 50 years old,among whom early-onset CRC incidence has been increasing.Screening and early detection are pivotal to improve CRC-related outcomes.It is well established that CRC screening not only reduces incidence,but also decreases deaths from CRC.Diverse screening strategies have proven effective in decreasing both CRC incidence and mortality,though variations in efficacy have been reported across the literature.However,uncertainties persist regarding the optimal screening method,age intervals and periodicity.Moreover,adherence to CRC screening remains globally low.In recent years,emerging technologies,notably artificial intelligence,and non-invasive biomarkers,have been developed to overcome these barriers.However,controversy exists over the actual impact of some of the new discoveries on CRC-related outcomes and how to effectively integrate them into daily practice.In this review,we aim to cover the current evidence surrounding CRC screening.We will further critically assess novel approaches under investigation,in an effort to differentiate promising inno-vations from mere novelties.

关键词： Colorectal cancer Screening Review Oncology Artificial intelligence

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A geomechanics classification for the rating of railroad subgrade performance

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Railway Engineering Science 2022年第3期30卷 323-359页

作者： Antonio Gomes Correia ana ramos Department of Civil Engineering ISISEUniversity of MinhoGuimara˜esPortugal

The type of subgrade of a railroad foundation is vital to the overall performance of the track structure.With the train speed and tonnage increase,as well as environmental changes,the evaluation and influence of subgrade are even more paramount in the railroad track structure performance.A geomechanics classification for subgrade is proposed coupling the stiffness(resilient modulus)and permanent deformation behaviour evaluated by means of repeated triaxial loading tests.This classification covers from fine-to coarse-grained soils,grouped by UIC and ASTM.For this achievement,we first summarize the main models for estimating resilient modulus and permanent deformation,including the evaluation of their robustness and their sensitivity to mechanical and environmental parameters.This is followed by the procedure required to arrive at the geomechanical classification and rating,as well as a discussion of the influence of environmental factors.This work is the first attempt to obtain a new geomechanical classification that can be a useful tool in the evaluation and modelling of the foundation of railway structures.

关键词： Subgrade Resilient modulus Permanent deformation Geomechanical classification

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Histological Assessment of Bone Regeneration in the Maxilla with Homologous Bone Graft:A Feasible Option for Maxillary Bone Reconstruction

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Journal of Renewable Materials 2024年第1期12卷 131-148页

作者： Sergio Henrique Gonçalves Motta ana Paula ramos Soares Juliana Campos Hasse Fernandes Gustavo Vicentis Oliveira Fernandes Graduate Center of Faculdade Redentor CLIVORio de JaneiroBrazil Periodontics and Oral Medicine Department University of Michigan School of DentistryAnn ArborMI48109USA Centre for Interdisciplinary Research in Health(CIIS) Universidade Católica PortuguesaViseu3504-505Portugal

Bone biomaterials have been increasingly used to reconstruct maxillary atrophic ridges.Thus,the aim of this study was to evaluate bone reconstruction in the maxilla using a homologous cortico-cancellous FFB(lyophilized)graft and verify its reliability.Eight individuals were included from 2014 to 2018.The first surgery was performed to install homologous bone blocks in the maxilla.The period of the second intervention varied between 5 months and 15 days to 11 months(≈7.93 months).The biopsies were taken from the central region of the matured graft during the surgery for implant placement.All patients presented clinical and radiographic conditions for the installation of dental implants.There was a 100%of survival rate.The histological assessment showed that the homologous block bone graft was an osteoconductive biomaterial,with connective tissue present,and newly formed bone juxtaposed on its surface.There were bone trabeculae with osteocytes and active osteoblasts with connective tissue in the mineralization process;the remodeling process can be found through the reverse lines.A limited focus of necrosis with fibrosis was detected,with small resorption and areas of inflammatory infiltrate,but without clinical significance.The homologous block bone graft can be considered a feasible option to substitute the autogenous bone graft(gold standard),with predictable clinical and favorable histological results.The patients had a shorter surgical period,low morbidity,and an unlimited amount of biomaterial available at an accessible cost.

关键词： Regeneration bone graft histology homologous allogenous autogenous

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Influence of train speed and its mitigation measures in the short-and long-term performance of a ballastless transition zone

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铁道工程科学:英文版 2023年第4期31卷 309-324页

作者： ana ramos Rui Calçada António Gomes Correia Department of Civil Engineering Faculty of EngineeringUniversity of PortoCONSTRUCT-LESEPortoPortugal Department of Civil Engineering University of MinhoISISEGuimarãesPortugal

The ballastless track is nowadays the most popular railway system due to the required low number of maintenance opera-tions and costs,despite the high investment.The gradual change from ballasted to ballastless tracks has been occurring in Asia,but also in Europe,increasing the number of transition zones.The transition zones are a special area of the railway networks where there is an accelerated process of track degradation,which is a major concern of the railway infrastructure managers.Thus,the accurate prediction of the short-and long-term performance of ballastless tracks in transition zones is an important topic in the current paradigm of building/rehabilitating high-speed lines.This work purposes the development of an advanced 3D model to study the global performance of a ballastless track in an embankment-tunnel transition zone considering the influence of the train speed(220,360,500,and 600 km/h).Moreover,a mitigation measure is also adopted to reduce the stress and displacements levels of the track in the transition.A resilient mat placed in the tunnel and embank-ment aims to soften the transition.The behaviour of the track with the resilient mat is evaluated considering the influence of the train speed,with special attention regarding the critical speed.The used methodology is a novel and hybrid approach that allows including short-term and long-term performance,through the development of a powerful 3D model combined with the implementation of a calibrated empirical permanent deformation model.

关键词： Ballastless track Train speed Numerical modelling Transition zone Critical speed

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Enhancement of the benthic communities around an isolated island in the Antarctic Ocean

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Acta Oceanologica Sinica 2013年第6期32卷 47-55页

作者： José I Saiz Nuria anadón Javier Cristobo Oscar García-Alvarez Gerardo García-Castrillo Eduardo López Cruz Palacín Jesús S Troncoso ana ramos Department of Zoology and Animal Cell Biology University of the Basque CountryBilbao 48080 Spain Department of Organisms and Systems Biology (Zoology) Rodrigo Uría s/n University of OviedoOviedo 33071 Spain Spanish Institute of Oceanography Gijón Oceanographic Centre Príncipe de Asturias 70bisGijón 33212 Spain Department of Zoology and Physical Anthropology University of Santiago de CompostelaSouth Campus Santiago de Compostela 15706 Spain Cantabrian Maritime Museum San Martín de Bajamar s/nSantander 39004 Spain Department of Biology Faculty of Sciences Autonomous University of MadridMadrid 28049 Spain Department of Animal Biology University of BarcelonaAvinguda Diagonal 645 Barcelona 08028 Spain Department of Ecology and Animal Biology Marine Sciences Faculty University of VigoVigo 36310 Spain Spanish Institute of Oceanography Subida a Radio Faro 50-52Vigo 36390 Spain

Insular marine biotas are often richer in faunal diversity than those from the open sea in the same geo- graphical region. The existence of particular island effects were tested under polar conditions by compar- ing infaunal benthic assemblages on Peter I Island with those of similar latitudes in the open ocean at the Bellingshausen Sea and also from the coast of the Antarctic Peninsula. Sampling was carried out aboard the R/V Hesperides during the expedition named BENTART-2003 from 24 January to 3 March 2003. Benthic samples were collected at 18 stations ranging from 90 to 2 044 m depth, using an USNEL-type box corer （BC） dredge. Representatives of 32 higher taxa of invertebrates were found. Univariate and multivariate analyses revealed various patterns in the data. First, significant differences in polychaete abundance were detected between the stations located in the open sea and the remaining sites （island plus mainland sites）. Bivalve abundances were also distinct between island and mainland sampling sites. Sediment columns taken from the island seafloor exhibited the highest rate of bioturbation by the infauna. These findings confirm the model that islands develop distinct assemblages characterized by the enhancement of the benthic commu- nities even in cold waters. Several abiotic factors were measured simultaneously at the seafloor and along the water column to investigate faunal distribution patterns. Significant correlations were found between the benthic assemblages and a combination of two environmental variables：＂island effect＂（measured as a categorical variable） and the redox state of sediments. Richer and more complex benthic assemblages were found in Peter I Island＇s sea bottom, whereas the more depauperate bottoms remained in the open sea.

关键词： Antarctica Bellingshausen Sea benthos Peter I Island PRIMER

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Neotropical mustelids: fecal metabolome diversity and its potential for taxonomic discrimination

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Integrative Zoology 2023年第3期18卷 518-529页

作者： Lana Resende de ALMEIDA Marina Amaral ALVES ana Maria Obino MASTELLA Rafael GARRETT Maria João ramos PEREIRA Bird and Mammal Evolution Systematics and Ecology LabPrograma de Pós-Graduação em Biologia AnimalUniversidade Federal do Rio Grande do SulPorto AlegreRio Grande do SulBrazil Programa de Pós-Graduação em Biologia Animal Universidade Federal do Rio Grande do SulPorto AlegreRio Grande do SulBrazil Chemistry Institute Metabolomics Laboratory(LabMeta–LADETEC/IQ–UFRJ)Avenida Horácio MacedoFederal University of Rio de JaneiroRio de JaneiroRJBrazil Walter Mors Institute of Research on Natural Products Universidade Federal do Rio de JaneiroRio de JaneiroRJBrazil

Chemical proﬁles of non-invasive biological material,such as feces,have great potential to study elusive animals or those with low population densities.Here,we use a metabolomic approach to evaluate Neotropical mustelids as a biological model to describe the diversity of the metabolites present in fecal samples,as well as to evaluate the potential of chemical proﬁles for taxonomic discrimination.We collected fecal samples from captive individuals of 5 species of mustelids occurring in Brazil and analyzed them by liquid chromatography coupled to high-resolution mass spectrometry.Over 200 compounds have been annotated;“bile acids,alcohols and derivatives”was the most expressive class in the metabolome of all the species.We successfully discriminated 3 taxonomic groups:1—tayra(Eira barbara);2—otters(Lontra longicaudis and Pteronura brasiliensis;1);and 3—grisons(Galictis vittata and Galictis cuja).Several compounds seemed to be associated with food intake and the digestive process,while others were found for theﬁrst time in Neotropical mustelids.We concluded that mustelids show high metabolome diversity and that species-speciﬁc identiﬁcation through metabolomic proﬁles is possible,thus contributing to the development and implementation of additional non-invasive approaches in the study of mustelids.

关键词： chemical proﬁles ecology high-resolution mass spectrometry metabolomics Mustelidae

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Machine learning insights concerning inflammatory and liver-related risk comorbidities in non-communicable and viral diseases

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World Journal of Gastroenterology 2022年第44期28卷 6230-6248页

作者： J Alfredo Martínez Marta Alonso-Bernáldez Diego Martínez-Urbistondo Juan A Vargas-Nuñez ana Ramírezde Molina Alberto Dávalos Omar ramos-Lopez Precision Nutrition and Cardiometabolic Health Madrid Institute of Advanced Studies-Food InstituteMadrid 28049Spain Department of Internal Medicine Hospital Universitario HM SanchinarroMadrid 28050Spain Servicio de Medicina Interna Hospital Universitario Puerta de Hierro MajadahondaMadrid 28222MajadahondaSpain Molecular Oncology and Nutritional Genomics of Cancer Madrid Institute of Advanced Studies-Food InstituteMadrid 28049Spain Laboratory of Epigenetics of Lipid Metabolism Madrid Institute of Advanced Studies-Food InstituteMadrid 28049Spain Medicine and Psychology School Autonomous University of Baja CaliforniaTijuana 22390Baja CaliforniaMexico

The liver is a key organ involved in a wide range of functions,whose damage can lead to chronic liver disease(CLD).CLD accounts for more than two million deaths worldwide,becoming a social and economic burden for most countries.Among the different factors that can cause CLD,alcohol abuse,viruses,drug treatments,and unhealthy dietary patterns top the list.These conditions prompt and perpetuate an inflammatory environment and oxidative stress imbalance that favor the development of hepatic fibrogenesis.High stages of fibrosis can eventually lead to cirrhosis or hepatocellular carcinoma(HCC).Despite the advances achieved in this field,new approaches are needed for the prevention,diagnosis,treatment,and prognosis of CLD.In this context,the scientific community is using machine learning(ML)algorithms to integrate and process vast amounts of data with unprecedented performance.ML techniques allow the integration of anthropometric,genetic,clinical,biochemical,dietary,lifestyle and omics data,giving new insights to tackle CLD and bringing personalized medicine a step closer.This review summarizes the investigations where ML techniques have been applied to study new approaches that could be used in inflammatoryrelated,hepatitis viruses-induced,and coronavirus disease 2019-induced liver damage and enlighten the factors involved in CLD development.

关键词： Machine learning Liver inflammation Liver disease Viral diseases Comorbidity

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REVISITING THE SIMILAR PROCESS TO ENGINEER THE CONTEMPORARY SYSTEMS

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Journal of Systems Science and Systems Engineering 2010年第3期19卷 321-350页

作者： ana Luísa ramos José Vasconcelos FERREIRA Jaume BARCELó GOVCOPP-Department of Economics Management and Industrial EngineeringUniversity of Aveiro Department of Statistics and Operations Research Technical University of Catalonia

This paper addresses the present-day context of Systems Engineering, revisiting and setting up an updated framework for the SIMILAR process in order to use it to engineer the contemporary systems. The contemporary world is crowded of large interdisciplinary complex systems made of other systems, personnel, hardware, software, information, processes, and facilities. An integrated holistic approach is crucial to develop these systems and take proper account of their multifaceted nature and numerous interrelationships. As the system＇s complexity and extent grow, the number of parties involved （stakeholders and shareholders） usually also raises, bringing to the interaction a considerable amount of points of view, skills, responsibilities, and interests. The Systems Engineering approach aims to tackle the complex and interdisciplinary whole of those socio-technical systems, providing the means to enable their successful realization. Its exploitation in our modern world is assuming an increasing relevance noticeable by emergent standards, academic papers, international conferences, and post-graduate programmes in the field. This work aims to provide ＂the picture＂ of modern Systems Engineering, and to update the context of the SIMILAR process model in order to use this renewed framework to engineer the challenging contemporary systems. The emerging trends in the field are also pointed-out with particular reference to the Model-Based Systems Engineering approach.

关键词： SIMILAR process systems engineering standards MBSE

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金融素养和网络能力对中小企业财务绩效的影响：市场导向的调节作用

金融素养和网络能力对中小企业财务绩效的影响：市场导向的调节作...

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作者： Araujo ramos ana Maria 浙江工商大学

学位级别：硕士

Small and Medium Enterprises（SMEs）play a fundamental role in enhancing a country economic development and job creation.SMEs need to maintain a good financial performance in order to survive and grow in today’s changing business environment.Recognizing the fact that SMEs are managed by on individual（manager/owner）,this study examines the impact of financial literacy and networking competency possessed by SMEs managers on their firms’ financial performance with emphasis on the potential moderating role of market orientation in Chinese and Peruvian contexts.At an initial stage,exploratory interviews were conducted with some SMEs’ managers about their perception and importance of financial literacy,networking competency,and market orientation in enhancing financial performance.Survey questionnaires were used to collect data from owners/managers of SMEs and data analyzed using structural equation modelling.Research finding showed a significant positive impact financial literacy and networking competency on SMEs financial performance in China and Peru.In Chinese context,market orientation was found to strengthen the impact of financial literacy and networking competency on SMEs financial performance,whereas in Peruvian context,market orientation was found to strengthen the relationship between networking competency and financial performance of SMEs only.Guided by the research findings,a set of recommendations to policy makers and managers of SMEs are withdrawn as well as identifying future areas of research.

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