Recursos de colección

Repositório Comum (38.362 recursos)

É um repositório para instituições de ensino e investigação produtoras de literatura científica cuja dimensão ainda não justifica a criação de um repositório próprio. Permite integrar instituições, grupos ou indivíduos na infra-estrutura do projecto, nomeadamente através das pesquisas do Portal RCAAP e da B-On.

Mostrando recursos 1 - 20 de 176

  1. Estilo de vida

    Azul, Ana Mano
    info:eu-repo/semantics/publishedVersion

  2. Estilo de vida

    Azul, Ana Mano
    info:eu-repo/semantics/publishedVersion

  3. Formação & (cons)ciência

    Azul, Ana Mano
    info:eu-repo/semantics/publishedVersion

  4. Formação & (cons)ciência

    Azul, Ana Mano
    info:eu-repo/semantics/publishedVersion

  5. Wilson’s sex fantasy questionnaire: Portuguese validation and gender differences

    Saramago, Mariana Amaral; Cardoso, Jorge Cardoso; Pimenta, Filipa; Leal, Isabel
    The main purpose of this study was to validate a Portuguese version of the Wilson’s Sex Fantasy Questionnaire. Afterwards, we assess the fantasies’ frequency based on gender differences. A community sample of 1220 Portuguese men and women completed the questionnaire with 40 items. Factor exploratory and confirmatory analysis, as well as comparative statistics for independent samples, were applied with the IBM SPSS Statistics and AMOS software (both v. 22.0, SPSS Inc., Chicago, Il., USA). The final structure with 24 items distributed amongst four factors showed overall good psychometric properties (in terms of factorial validity, reliability and sensitivity) and questionable convergent...

  6. Wilson’s sex fantasy questionnaire: Portuguese validation and gender differences

    Saramago, Mariana Amaral; Cardoso, Jorge Cardoso; Pimenta, Filipa; Leal, Isabel
    The main purpose of this study was to validate a Portuguese version of the Wilson’s Sex Fantasy Questionnaire. Afterwards, we assess the fantasies’ frequency based on gender differences. A community sample of 1220 Portuguese men and women completed the questionnaire with 40 items. Factor exploratory and confirmatory analysis, as well as comparative statistics for independent samples, were applied with the IBM SPSS Statistics and AMOS software (both v. 22.0, SPSS Inc., Chicago, Il., USA). The final structure with 24 items distributed amongst four factors showed overall good psychometric properties (in terms of factorial validity, reliability and sensitivity) and questionable convergent...

  7. Effect of bleaching teeth with hydrogen peroxide on the morphology, hydrophilicity, and mechanical and tribological properties of the enamel

    Rodrigues, F. T.; Serro, A. P.; Polido, M.; Ramalho, A.; Figueiredo-Pina, C. G.
    The tooth whitening process is intended to restore the original color of teeth. It consists of the application of oxidizing agents, including hydrogen peroxide. Although these products considerably improve the color of teeth, their effects on other properties of enamel are not fully understood. This work aimed to study the effects of hydrogen peroxide concentration on hydrophilicity, roughness, morphology, and mechanical and tribological properties of human tooth enamel. Human teeth were subjected to bleaching sessions with 6%, 15%, and 35% hydrogen peroxide to achieve a similar level of whitening. The enamel roughness and morphology were characterized by atomic force microscopy...

  8. Tribological behavior of unveneered and veneered lithium disilicate dental material

    Figueiredo-Pina, C. G.; Patas, N.; Canhoto, J.; Cláudio, R.; Olhero, S.M.; Serro, A.P.; Ferro, A.C.; Guedes, M.
    The friction and wear behaviour of a lithium disilicate dental ceramic against natural dental enamel is studied, including the effect of the presence of a fluorapatite veneering upon the tribological properties of the material. The tribological behaviour was assessed using reciprocating pin-on-plate test configuration, at pH 3 and pH 7. The surface energy of the plates was determined, as well as the zeta potential of fluorapatite, lithium disilicate and enamel particles in artificial saliva. It was found that the friction and wear behaviour of the tested enamel/plate material tribocouples is less severe in unveneered plates. Initial surface roughness of the plate...

  9. Tribological behavior of unveneered and veneered lithium disilicate dental material

    Figueiredo-Pina, C. G.; Patas, N.; Canhoto, J.; Cláudio, R.; Olhero, S.M.; Serro, A.P.; Ferro, A.C.; Guedes, M.
    The friction and wear behaviour of a lithium disilicate dental ceramic against natural dental enamel is studied, including the effect of the presence of a fluorapatite veneering upon the tribological properties of the material. The tribological behaviour was assessed using reciprocating pin-on-plate test configuration, at pH 3 and pH 7. The surface energy of the plates was determined, as well as the zeta potential of fluorapatite, lithium disilicate and enamel particles in artificial saliva. It was found that the friction and wear behaviour of the tested enamel/plate material tribocouples is less severe in unveneered plates. Initial surface roughness of the plate...

  10. Simulation of the hydrodynamic conditions of the eye to better reproduce the drug release from hydrogel contact lenses: experiments and modeling

    Pimenta, A. F. R.; Valente, A.; Pereira, J. M. C.; Pereira, J. C. F.; Filipe, H. P.; Mata, J. L. G.; Colaço, R.; Saramago, B.; Serro, A. P.
    The final publication is available at Springer via http://dx.doi.org/10.1007/s13346-016-0303-1

  11. Simulation of the hydrodynamic conditions of the eye to better reproduce the drug release from hydrogel contact lenses: experiments and modeling

    Pimenta, A. F. R.; Valente, A.; Pereira, J. M. C.; Pereira, J. C. F.; Filipe, H. P.; Mata, J. L. G.; Colaço, R.; Saramago, B.; Serro, A. P.
    The final publication is available at Springer via http://dx.doi.org/10.1007/s13346-016-0303-1

  12. Interaction of the Alzheimer Aβ(25–35) peptide segment with model membranes

    Cuco, Andreia; Serro, Ana Paula; Farinha, José Paulo; Saramago, Benilde; Silva, Amélia Gonçalves da
    Alzheimer’s disease is characterized by the presence of amyloid plaques in the brain. The main components of these plaques are the Aβ(1–40) and Aβ(1–42) peptides but the Aβ(25–35) sequence is the most frequently studied fragment because it represents a biologically active region of the longer Aβ peptides. In the present work, the interactions of Aβ(25–35) peptide with model membranes were investigated, taking into consideration the aggregation state of the peptide. Monolayers and liposomes were taken as model membranes with two lipid compositions: the equimolar ternary mixture of 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC), sphingomyelin (SM), and cholesterol (Chol) and the equimolar POPC/SM binary mixture....

  13. Interaction of the Alzheimer Aβ(25–35) peptide segment with model membranes

    Cuco, Andreia; Serro, Ana Paula; Farinha, José Paulo; Saramago, Benilde; Silva, Amélia Gonçalves da
    Alzheimer’s disease is characterized by the presence of amyloid plaques in the brain. The main components of these plaques are the Aβ(1–40) and Aβ(1–42) peptides but the Aβ(25–35) sequence is the most frequently studied fragment because it represents a biologically active region of the longer Aβ peptides. In the present work, the interactions of Aβ(25–35) peptide with model membranes were investigated, taking into consideration the aggregation state of the peptide. Monolayers and liposomes were taken as model membranes with two lipid compositions: the equimolar ternary mixture of 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC), sphingomyelin (SM), and cholesterol (Chol) and the equimolar POPC/SM binary mixture....

  14. Femtosecond laser surface texturing of titanium as a method to reduce the adhesion of Staphylococcus aureus and biofilm formation

    Cunha, Alexandre; Elie, Anne-Marie; Plawinski, Laurent; Serro, Ana Paula; Rego, Ana Maria Botelho do; Almeida, Amélia; Urdaci, Maria C.; Durrieu, Marie-Christine; Vilar, Rui Vilar
    The aim of the present work was to investigate the possibility of using femtosecond laser surface texturing as a method to reduce the colonization of Grade 2 Titanium alloy surfaces by Staphylococcus aureus and the subsequent formation of biofilm. The laser treatments were carried out with a Yb:KYW chirped-pulse-regenerative amplification laser system with a central wavelength of 1030 nm and a pulse duration of 500 fs. Two types of surface textures, consisting of laser-induced periodic surface structures (LIPSS) and nanopillars, were produced. The topography, chemical composition and phase constitution of these surfaces were investigated by atomic force microscopy, scanning electron...

  15. Femtosecond laser surface texturing of titanium as a method to reduce the adhesion of Staphylococcus aureus and biofilm formation

    Cunha, Alexandre; Elie, Anne-Marie; Plawinski, Laurent; Serro, Ana Paula; Rego, Ana Maria Botelho do; Almeida, Amélia; Urdaci, Maria C.; Durrieu, Marie-Christine; Vilar, Rui Vilar
    The aim of the present work was to investigate the possibility of using femtosecond laser surface texturing as a method to reduce the colonization of Grade 2 Titanium alloy surfaces by Staphylococcus aureus and the subsequent formation of biofilm. The laser treatments were carried out with a Yb:KYW chirped-pulse-regenerative amplification laser system with a central wavelength of 1030 nm and a pulse duration of 500 fs. Two types of surface textures, consisting of laser-induced periodic surface structures (LIPSS) and nanopillars, were produced. The topography, chemical composition and phase constitution of these surfaces were investigated by atomic force microscopy, scanning electron...

  16. Drug release from liposome coated hydrogels for soft contact lenses: the blinking and temperature effect

    Paradiso, P.; Colaço, R.; Mata, J. L. G.; Krastev, R.; Saramago, B.; Serro, A. P.
    This is the accepted version of the following article: J Biomed Mater Res B Appl Biomater. 2017 Oct;105(7):1799-1807, which has been published in final form at http://dx.doi.org/10.1002/jbm.b.33715. This article may be used for non-commercial purposes in accordance with the Wiley Self-Archiving Policy [http://olabout.wiley.com/WileyCDA/Section/id-820227.html].

  17. Drug release from liposome coated hydrogels for soft contact lenses: the blinking and temperature effect

    Paradiso, P.; Colaço, R.; Mata, J. L. G.; Krastev, R.; Saramago, B.; Serro, A. P.
    This is the accepted version of the following article: J Biomed Mater Res B Appl Biomater. 2017 Oct;105(7):1799-1807, which has been published in final form at http://dx.doi.org/10.1002/jbm.b.33715. This article may be used for non-commercial purposes in accordance with the Wiley Self-Archiving Policy [http://olabout.wiley.com/WileyCDA/Section/id-820227.html].

  18. Controlled drug release from hydrogels for contact lenses: drug partitioning and diffusion

    Pimenta, A.F.R.; Ascenso, J.; Fernandes, J.C.S.; Colaço, R.; Serro, A.P.; Saramago, B.
    Optimization of drug delivery from drug loaded contact lenses assumes understanding the drug transport mechanisms through hydrogels which relies on the knowledge of drug partition and diffusion coefficients. We chose, as model systems, two materials used in contact lens, a poly-hydroxyethylmethacrylate (pHEMA) based hydrogel and a silicone based hydrogel, and three drugs with different sizes and charges: chlorhexidine, levofloxacin and diclofenac. Equilibrium partition coefficients were determined at different ionic strength and pH, using water (pH 5.6) and PBS (pH 7.4). The measured partition coefficients were related with the polymer volume fraction in the hydrogel, through the introduction of an enhancement...

  19. Controlled drug release from hydrogels for contact lenses: drug partitioning and diffusion

    Pimenta, A.F.R.; Ascenso, J.; Fernandes, J.C.S.; Colaço, R.; Serro, A.P.; Saramago, B.
    Optimization of drug delivery from drug loaded contact lenses assumes understanding the drug transport mechanisms through hydrogels which relies on the knowledge of drug partition and diffusion coefficients. We chose, as model systems, two materials used in contact lens, a poly-hydroxyethylmethacrylate (pHEMA) based hydrogel and a silicone based hydrogel, and three drugs with different sizes and charges: chlorhexidine, levofloxacin and diclofenac. Equilibrium partition coefficients were determined at different ionic strength and pH, using water (pH 5.6) and PBS (pH 7.4). The measured partition coefficients were related with the polymer volume fraction in the hydrogel, through the introduction of an enhancement...

  20. Chitosan/alginate based multilayers to control drug release fromophthalmic lens

    Silva, Diana; Pinto, Luís F. V.; Bozukova, Dimitriya; Santos, Luís F.; Serro, Ana Paula; Saramago, Benilde
    In this study we investigated the possibility of using layer-by-layer deposition, based in natural polymers (chitosan and alginate), to control the release of different ophthalmic drugs from three types of lens materials: a silicone-based hydrogel recently proposed by our group as drug releasing soft contact lens (SCL) material and two commercially available materials: CI26Y for intraocular lens (IOLs) and Definitive 50 for SCLs. The optimised coating, consisting in one double layer of (alginate – CaCl2)/(chitosan + glyoxal) topped with a final alginate-CaCl2 layer to avoid chitosan degradation by tear fluid proteins, proved to have excellent features to control the release...

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