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Characterization of the Topography and Wettability of English Weed Leaves and Biomimetic Replicas

Journal of Bionic Engineering 2014年第3期11卷 346-359页

作者： Pedro Miguel Matos Pereira ana sofia moita Gabriel Amaro Monteiro Duarte Miguel Franca Prazeres IBB - Institute for Biotechnology and Bioengineering Centre for Biological and Chemical Engineering Department of Bioengineering Instituto Superior Tecnico Universidade de Lisboa Av. Rovisco Pals 1049-001 Lisboa Portugal IN+ - Center for Innovation Technology and Policy Research Instituto Superior T~cnico Universidade de Lisboa Av. Rovisco Pais 1049-001 Lisboa Portugal

The topography and wettability of the underside of English weed （Oxalis pes-caprae） leaves and of their biomimetic replicas are investigated. Polyvinyl siloxane molds were cast from the leaves and then filled with an epoxy pre-polymer to produce replicas. The particular topographical structures of leaves and replicas were evaluated by optical microscopy and Scanning Electron Microscopy （SEM） analysis. The static wettability of leaves and replicas was assessed by contact angle measurements, while the dynamic wettability was characterized by estimating contact angle hysteresis and studying the dynamic behavior of impacting water droplets. A smooth glass slip and its replica were used as control surfaces. The replica moulding method used was able to transfer the characteristic pattern of irregular 100 μm - 200 μm × 60 μm convex papillae interspersed with stomata of the original leaf to the epoxy replicas. The static contact angle of 143°± 3° and the contact angle hysteresis of 2~ indicate that the underside of the English weed leaf is close to superhydrophobic. The lower contact angles （130° ± 4°） and higher hysteresis （31°） observed for the replica when compared with the original leaves were associated to an inaccurate replication of the chemistry and structures of the three-dimensional wax projections covering the plant surface. Also, trichomes in the original leaves could not be accurately reproduced due to their flexibility and fragility. Differences in wetting behavior were also evident from droplet impact experiments, with rebound regimes prevailing in the original leaves and regimes characterized by higher adhesion and larger dissipation predominating in the replicas. Nevertheless, the morphological features of the leaf transferred to the replica were sufficient to promote a clear hydrophobic behavior of the replica when compared with the smooth epoxy reference surface.

关键词： biomimetic surfaces oxalis pes-caprae English weed replica molding wettability micro-topography

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Dynamics of Droplets of Biological Fluids on Smooth Superhydrophobic Surfaces under Electrostatic Actuation

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Journal of Bionic Engineering 2016年第2期13卷 220-234页

作者： ana sofia moita Catarina Laurencia Joana anastacio Ramos Duarte Miguel Franca Prazeres Antonio Luis Nobre Moreira IN+ - Center for Innovation Technology and Policy Research Instituto Superior Tecnico Universidade de Lisboa Av. Rovisco Pais 1049-001 Lisboa Portugal iBB - Institute for Bioengineering and Biosciences Department of Bioengineering Instituto Superior Tecnico Universidade de Lisboa Av. Rovisco Pais 1049-001 Lisboa Portugal

This study describes the dynamic behaviour of droplets of biological liquids on hydrophobic surfaces under electrostatic actuation, to devise sample handling in lab-on-chip diagnostic tools. Bovine Serum Albumin （BSA） is taken as a representative biomolecule, since it is often used in adsorption studies. Green Fluorescence Protein （GFP） is also considered, given its natural fluorescence. Several effects such as sample concentration and pH are discussed. The results show negligible effects of proteins concentration in electrowetting, although increased concentrations endorse passive adsorption mechanisms, which alter the local wettability of the substrates precluding droplet motion. Bioinspired surfaces promote the largest spreading diameter, which is beneficial for droplet motion. However, surface roughness promotes energy dissipation limiting the receding droplet motion. Hence, the most effective approach is altering the surface chemistry. The coating is applied to a surface with a mean roughness smaller than 20 nm and does not alter significantly the topography, thus leading to the so-called smooth superhydrophobic surface. This coating also reduces passive proteins adsorption, as confirmed by Confocal Microscopy （CM）, which is beneficial for droplet motion. Evaluating absorption spectra of protein solutions evidences an increase in protein concentration ascribed to droplet evaporation as confirmed by theoretical analysis and time resolved infrared visualization.

关键词： bioinspired surfaces biofluids electrostatic actuation hydrophobicity adsorption evaporation

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Application of Bioinspired Superhydrophobic Surfaces in Two-phase Heat Transfer Experiments

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Journal of Bionic Engineering 2017年第3期14卷 506-519页

作者： Emanuele Teodori ana sofia moita Miguel Moura Pedro Pontes Antonio Moreira Yuan Bai Xinlin Li Yan Liu IN+- Center for Innovation Technology and Policy Research Instituto Superior T~enico Universidade de Lisboa Av. Rovisco Pais 1049-001 Lisboa Portuga Key Laboratory of Bionic Engineering (Ministry of Education) Jilin University Changchun 130022 China

This paper addresses the potential to use Lotus leafbioinspired surfaces in applications involving heat transfer with phase change, namely pool boiling and spray impingement. Besides describing the role of bioinspired topographical features, using an innovative technique combining high-speed visualization and time-resolved infrared thermography, surface durability is also addressed. Water is used for pool boiling and for spray impingement systems （simplified as single droplet impact）, while HFE7000 is used in a pool boiling cooler for electronic components. Results show that surface durability is quickly compro- mised for water pool boiling applications, as the chemical treatment does not withstand high temperatures （T 〉 100 ℃） during long time intervals （3 h - 4 h）. For HFE7000 pool boiling （depicting lower saturation temperature - 34 ℃）, heat transfer en- hancement is governed by the topography. The regular hierarchical pattern of the bioinspired surfaces promotes the heat transfer coefficient to increase up to 22.2%, when compared to smooth surfaces, while allowing good control of the interaction mechanisms until a distance between micro-structures of 300 gm- 400 Ixm. Droplet impingement was studied for surface temperatures ranging between 60 ℃ - 100 ℃. The results do not support the use of superhydrophobic surfaces for cooling applications, but reveal great potential for other applications involving droplet impact on heated surfaces （e.g. metallurgy in- dustry）.

关键词： bioinspired surfaces surface micro-patterning two-phase heat transfer time resolved infrared thermography

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Bubble Dynamics and Heat Transfer on Biphilic Surfaces:Experiments and Numerical Simulation

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Journal of Bionic Engineering 2020年第4期17卷 809-821页

作者： Pedro Pontes Ricardo Cautela Emanuele Teodori ana sofia moita anastasios Georgoulas António Luís Nobre Moreira Moreira IN+-Center for Innovation Technology and Policy ResearchDepartment of Mechanical EngineeringInstituto Superior TécnicoUniversidade de LisboaAv.Rovisco Pais1049-001 LisboaPortugal ASML Holding N.V. De Run 65015504 DRVeldhovenThe Netherlands Department of Exact Sciences and Engineering Portuguese Military AcademyR.Gomes Freire2031169-203 LisboaPortugal Advanced Engineering Centre School of ComputingEngineering and MathematicsCockcroft BuildingLewes RoadUniversity of Brighton BN24GJUK

Wettability is known to play a major role in enhancing pool boiling heat *** this context bioinspired surfaces can bring significant advantages in pool boiling *** work addresses a numerical investigation of bubble growth and detachment on a biphilic surface pattern,namely in a superhydrophobic region surrounded by a hydrophilic *** characteristics resemble bioinspired solutions explored in our research group,mainly considering the main topographical *** numerical approach is intended to provide additional information to an experimental approach,allowing to obtain temperature,pressure and velocity fields in and around the bubble,which help to describe bubble *** model was validated based on experimental data obtained with extensive image processing of synchronized high-speed video and high-speed thermographic *** results obtained here clearly evidence that combining enhanced direct numerical simulations with high-resolution transient experimental measurements is a promising tool to describe the complex and intricate hydrodynamic and heat transfer phenomena governing pool boiling on heated biphilic surfaces.

关键词： bioinspired biphilic surfaces bubble dynamics two-phase heat transfer time resolved infrared thermography CFD model

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Design multifunctional Mg–Zr coatings regulating Mg alloy bioabsorption

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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 ***,rapid degradation and inadequate strength limit their *** overcome this,the direct current magnetron sputtering technique is employed for surface coating in Mg-based alloys using various zirconium(Zr)*** approach presents a promising strategy for simultaneously improving corrosion resistance,maintaining biocompatibility,and enhancing strength without compromising *** leveraging Mg’s inherent biodegradability,it has the potential to minimize the need for secondary surgeries,thereby reducing costs and *** 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 *** 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 ***,the hardness has significantly improved across all samples’coating,reaching the highest value of(2.2±0.3)GPa for 5 at.%*** 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.%*** 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/*** 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 consequentl

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

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Testicular prostheses-impact on quality of life and sexual function

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Asian Journal of Andrology 2024年第2期26卷 160-164页

作者： ana sofia Araujo Sara anacleto Ricardo Rodrigues Catarina Tinoco Andreia Cardoso Carlos Oliveira Ricardo Leao Department of Urology Braga's HospitalBraga 4710Portugal Faculty of Medicine Coimbra UniversityCoimbra 3000Portugal

Orchiectomy is the recommended treatment for many testicular ***,testicular prosthesis placement is not always performed for different *** this study,we aimed to evaluate patients'opinions and the impact on sexual function and quality of *** retrospective observational single-center study included patients who underwent orchiectomy between January 2014 and December 2020 at the Department of Urology,Braga's Hospital(Braga,Portugal),where testicular implants were always available and the decision to undergo the procedure was made fully independent of *** completed four questionnaires that assessed demographic data,satisfaction,self-esteem,and sexual *** the 96 patients who underwent orchidectomy,59 replied to the questionnaires,and of these patients,86.4%decided to undergo silicone-based testicular prostheses *** remaining 13.6%refused the implant based on concerns about complications(37.5%),because they felt that it was unnecessary(37.5%),or because it was not offered by the doctor(25.0%).Overall,96.1%of these patients were satisfied with the implant;however,25.5%classified it as"too firm".No statistically significant differences were found in sexual function(all P>0.05).However,it can be observed that there are more patients with prostheses presenting normal sexual activity compared to patients without prostheses(74.0%vs 50.0%),and none of them reported severe erectile dysfunction(0 vs 16.7%).Regarding self-esteem,both patients with and without prostheses present very similar average scores with no statistically significant *** present study highlights the highest level of satisfaction among patients who received testicular *** prostheses implantation is a safe procedure that does not hamper sexual function after orchiectomy.

关键词： orchiectomy patient satisfaction quality of life sexual dysfunction sexual health testicular prostheses

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Genetic variation at the p53 locus of two ecologically divergent Microtus pine voles:identification of molecular markers for species assignment

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Integrative Zoology 2022年第6期17卷 1179-1192页

作者： ana sofia QUINA João Paulo TAVANEZ Maria da Luz MATHIAS CESAM-Centro de Estudos do Ambiente e do Mar Departamento de BiologiaUniversidade de AveiroAveiroPortugal CESAM-Centro de Estudos do Ambiente e do Mar Faculdade de CiênciasUniversidade de LisboaLisboaPortugal Departamento de Biologia Animal Faculdade de CiênciasUniversidade de LisboaLisboaPortugal Global Health and Tropical Medicine(GHTM) Instituto de Higiene e Medicina Tropical(IHMT)Universidade NOVA de Lisboa(UNL)Portugal

The Lusitanian(Microtus lusitanicus)and the Mediterranean(Microtus duodecimcostatus)pine voles are recently diverged sister species endemic of the Iberian Peninsula that can be identiﬁed with ecological and morphological characters,but in areas where the 2 species co-occur,species designation may be difﬁ*** discrimination between *** and *** has not been achieved yet possibly because of their estimated re-cent split and an evolutionary history that includes inter-species geneﬂ*** our previous observations on exons 5–7 of the p53 gene,here we analyze the potential use of the p53 genomic region as a discrimination marker of these species by extending our analyses to several kb upstream and downstream of the p53 gene and charac-terizing the degree of genetic differentiation in 7 markers within this ***,we fully sequenced the P53 protein of both *** observed:(i)generally high differentiation in this region;(ii)*** showed in general higher values of nucleotide and haplotype diversities;(iii)the concatenated phylogenetic tree separates the 2 species;(iv)the 2 P53 proteins only differ in 1 amino acid;(v)4 of the markers,2 in p53,one in Atp1b2,and another in Wrap53,contain species-speciﬁc genetic variation thus allowing a reliable discrimination between specimens from both species,irrespective of sampling location or introgression *** provide ad-ditional data on the putative role of p53 in the evolution of these species and present researchers with a fast and cost-effective resource for *** and *** identiﬁcation.

关键词： ecological stress genetic variation Microtus molecular marker p53

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Validation of the Portuguese version of the social isolation scale with a sample of community-dwelling older adults

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International Journal of Nursing Sciences 2023年第2期10卷 151-157页

作者： João Tavares ana Faria Delphine Gonçalves Diana Mendes sofia Silva Liliana Sousa Health School University of AveiroAveiroPortugal Center for Health Technology and Services Research(CINTESIS@RISE) Portugal Health Sciences Research Unit:Nursing(UICISA:E) Portugal Department of Education and Psychology University of AveiroAveiroPortugal The Polytechnic Institute of Coimbra Coimbra Education SchoolCoimbraPortugal

Objectives The aim of this study was to analyze the psychometric properties(reliability and validity)of the Social Isolation Scale(SIS)in a sample of Portuguese community-dwelling older *** A transversal descriptive study was carried out with a convenience sample of 250 community-dwelling older adults(≥65 years).The survey comprised a sociodemographic questionnaire,SIS,Geriatric Depression Scale-4(GDS-4),6-item Lubben Social Network Scale(LSNS-6),a loneliness self-assessment question,and Satisfaction with Life Scale(SWLS).Construct validity(confirmatory factor analysis)and convergent validity were analyzed,and ISI internal reliability(composite reliability),external reliability(test-retest,intraclass correlation coefficient)and inter-rater reliability(Cohen’s kappa coefficient)were *** Confirmatory factor analysis showed a two-factor model with an excellent index of *** SIS showed significant correlations with LSNS-6(rs=0.47),SWLS(rs=0.26),the loneliness self-assessment question(rs=0.35),and GDS-4(rs=−0.16).SIS composite reliability was good(0.708).The inter-class correlation coefficient varied from 0.84 to *** Cohen’s kappa coefficient ranged from 0.936 to *** SIS has been shown to be a valid and reliable instrument for assessing social isolation among Portuguese community-dwelling older *** professionals,particularly nurses working in community settings,can use SIS to assess social isolation in older adults to design,implement,and evaluate interventions.

关键词： Aged Loneliness Portugal Psychometrics Social isolation

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The Influence of High Temperature Exposure on the Wear Performance of a Ni Based Alloy PTA Coating

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材料热处理学报 2004年第5期25卷 152-156页

作者： Karin Graf ana sofia C.M. d'OIiveira Mechanical Department of Universidade Federal do Parana Curitiba BrazilMechanical Department of Universidade Federal do Parana Curitiba Brazil

Degradation phenomena like wear and corrosion, may have their effects accelerated as components operate at high temperature. The aim of this work is to make an indirect evaluation of the influence of high temperature exposure on wear behavior of Ni coatings. A Ni-Cr-Mo-W alloy, was deposited with Plasma Transferred Arc (PTA) process. An indirect approach based on the Ahrrenius relationship was used to evaluated long time exposures at high temperatures. To simulate longer exposures at lower temperatures, coatings were exposed to higher temperatures for the same time interval. So coatings were soaked in an air furnace at 650°C, 1000°C and 1200°C. Metal/metal wear behavior was evaluated by pin-on-disc tests. Pins were removed from the coatings by eletrodischarge machining and rubbed against a VC31 quenched and tempered tool steel. Two sets of wear tests were run at 2m/s, for different loads (0.5, 1.0, 2.0 and 3.0Kg) and for different sliding distances (120, 720, 1080, 1440 and 1800m).Coatings characterization was done by scanning electronic microscopy and Vickers microhardness. Results showed as temperature is increased, coatings wear performance is altered, and this is associated with microstructural changes.

关键词：磨损 Ni合金 PTA 高温曝露

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Children in Disaster Risk Reduction in Portugal: Policies,Education,and (Non) Participation

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International Journal of Disaster Risk Science 2017年第3期8卷 246-257页

作者： ana Delicado ussara Rowland Susana Fonseca ana Nunes de Almeida Luísa Schmidt ana sofia Ribeiro Instituto de Ciências Sociais Universidade de Lisboa1600-189 LisbonPortugal

International agencies and scientific research have been calling for the inclusion of children in disaster preparedness and risk reduction, to hear their voices in order to address their specific needs and vulnerabilities and harness their capabilities in terms of building community resilience. This article assesses the roles ascribed to children in policy and education for disaster risk reduction in Portugal. The approach is based on a scoping methodology that encompasses document analysis and interviews with national and local stakeholders and policymakers in the disaster risk reduction field. The research is carried out within the scope of a European funded project, CUIDAR Cultures of Disaster Resilience among Children and Young People. More specifically, the article provides an overview of the discourses on the roles ascribed to children in urban disaster risk reduction(DRR). The authors maintain that although children are often taken as a target group in urban disaster prevention and management, they are seldom considered in terms of active participation in disaster risk reduction programs in the Portuguese context. Nevertheless, our analysis shows that there is a growing awareness of the relevance of active participation by children in order to create successful DRR.

关键词：孩子不参与灾难风险减小紧急情况计划葡萄牙冒险教育

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