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2010
Santos, HM, Carreira R, Diniz MS, Rivas MG, Lodeiro C, Moura JJ, Capelo JL.  2010.  Ultrasonic multiprobe as a new tool to overcome the bottleneck of throughput in workflows for protein identification relaying on ultrasonic energy, Apr 15. Talanta. 81:55-62., Number 1-2 AbstractWebsite

We studied in this work the performance of the new ultrasonic multiprobe in terms of throughput, handling and robustness. The study was conducted using the multiprobe to speed two different proteomics workflows. The "classic" method relaying on overnight protein digestion (12h), was used as the standard procedure. This work clearly shows the importance of testing variables such as ultrasonic amplitude and ultrasonic time when adapting an ultrasonic-based treatment to a new ultrasonic device. The results here presented also shown and confirm the advantage of speed up sample treatment workflows with the aid of ultrasonic energy in combination with a 96-well plate. The methods compared were similar in terms of robustness, but the desalting free method was the fastest, requiring only 2 min/sample for completion. In addition it was also the simplest in terms of handling, since no desalting step was needed. The following standard proteins were successfully identified using the methods studied: bovine serum albumin, alpha-lactalbumin, ovalbumin, carbonic anhydrase, fructose-bisphosphate aldolase A, catalase, chymotrypsinogen A. As case study, the identification of the protein Split-Soret cytochrome c from D. desulfuricans ATCC 27774 was carried out.

Pontes, H, de Pinho PG, Fernandes E, Branco PS, Ferreira LM, Carmo H, Remiao F, Carvalho F, Bastos ML.  2010.  Metabolic interactions between ethanol and MDMA in primary cultured rat hepatocytes, APR 11. TOXICOLOGY. 270:150-157., Number 2-3 Abstract

3,4-Methylenedioxymethamphetamine (MDMA; ecstasy), a drug of abuse commonly consumed at rave parties, is often taken in a polydrug abuse scenario, ethanol being one of the most associated drugs. Both MDMA and ethanol are mainly metabolized in the liver with formation of toxic metabolites. Our working hypothesis is that ethanol can modify the metabolism of MDMA through the cytochrome P450 system, and that this effect may be further potentiated by hyperthermia, a well-known consequence of MDMA abuse. To investigate these putative interactions we used primary rat hepatocyte cultures, which were exposed to 300 mM ethanol, 1.6 mM MDMA and the combination of both, at normothermic (36.5 degrees C) and hyperthermic (40.5 degrees C) conditions. After 24 h, the levels of MDA, HMA and HMMA in the cell culture medium were quantified by GC/MS. In addition, we repeated the same experimental design preceded by 1 h incubation with 0.18 mu M ketoconazole or 150 mu M diallyl sulphide (CYP3A and CYP2E1 inhibitors, respectively), to evaluate the putative role of these isoenzymes in the observed effects. The results obtained showed that ethanol exposure increases the formation of some MDMA metabolites such as HMA (1.8 times increase) and MDA (1.5 times increase). This effect was markedly increased under hyperthermic conditions (HMA, MDA and HMMA formation increased 10,6 and 16 times, respectively) and is mediated, at least partially, by CYP3A and CYP2E1. (C) 2010 Elsevier Ireland Ltd. All rights reserved.

and F.M. Braz Fernandes, K.K. Mahesh, RJCSSMRM.  2010.  Simultaneous measurement of electrical resistivity and x-ray diffraction during R-phase formation on Ni-Ti SMA, 6-7 Apr, 2010. Smart Structural Systems Technology - 2010. , Porto, Portugal: European Science Foundation2010-simultaneous_measurement_of_electrical_resistivity_and_x-ray_diffraction_during_r-phase_formation_on_ni-ti_sma..pdf
Moniz, AB.  2010.  Anthropocentric-based robotic and autonomous systems: assessment for new organisational options, 5-6 Nov. 2009. Conference "Autonomous systems: inter-relations of technical and societal issues". , Monte de Caparica: IET Abstract

Research activities at European level on the concept of new working environments offers considerable attention to the challenges of the increased competencies of people working together with automated technologies. Since the decade of 1980 the development of approaches for the humanization of work organization, and for the development of participative organizational options induced to new proposals related to the development of complex and integrated automated systems. From such parallel conceptual development emerged the concept of “anthropocentric robotic systems” and quickly it covered also other fields of automation. More recently, the debate also covers issues related to working perception of people dealing with autonomous systems (e.g. Autonomous robotics) in tasks related to production planning, to programming and to process control. In fact, today one can understand the wider use of the anthropocentrism concept of production architectures, when understanding the new quality of these systems. In this chapter the author analyses the evolution of these issues related to governance of ICT applied to manufacturing and industrial services in research programmes strengthening very much the ‘classical’ concept of anthropocentric-based systems. It is emerging a new value of the intuitive capacities and human knowledge in the optimization and flexibilization of the manufacturing processes. While this would be a pre-condition to understand the human-robot communication needs, there is also a need to take into consideration the qualitative variables in the definition and design of robotic systems, jobs and production systems.

Gouveia, JP, Fortes P, Seixas J.  2010.  Forecasting of Residential Energy Services Demand: The Portuguese Case for 2030, 25-28 August. International Conference IAEE - 11th IAEE European Conference Energy Economy, Policies and Supply Security: Surviving the Global Economic Crisis.. , Vilnius, Lithuania: International Association of Energy Economics
Dias, L, Gouveia J, Maurício B, Fortes P, Seixas J.  2010.  The impact of Climate Change Mitigation Options on Air Pollutant Emissions in Portugal, 24 June. Semiannual ETSAP Meeting 2010. , Stockholm, Sweden: KTH Royal Institute of Technology
Rosado, LS, Santos TG, Piedade M, Ramos PM, Vilaça P.  2010.  Advanced technique for non-destructive testing of friction stir welding of metals, 2010. Measurement: Journal of the International Measurement Confederation. 43(8):1021-1030. AbstractWebsite
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Gavara, R, Laia CAT, Parola AJ, Pina F.  2010.  Formation of a leuco Spirolactone from 4-(2-Carboxyphenyl)-7-diethylamino-4 '-dimethylamino-1-benzopyrylium: Design of a Phase-Change Thermochromic System Based on a Flavylium Dye, 2010. Chemistry-a European Journal. 16:7760-7766. AbstractWebsite

A phase-change thermochromic system was designed through the reversible transformation of the 4-substituted flavylium dye 4-(2-carboxyphenyl)-7-diethylamino-4'-dimethyl-amino-1-benzopyrylium into its leuco form, in the presence of a developer (ethyldiisopropylamine) and a suitable solvent (e.g., acetonitrile, n-pentadecanonitrile). The leuco form of the flavylium-based dye is a spirolactone species whose ring opens at low temperature (below the solvent melting point) to form the blue flavylium cation. Decarboxylation of the lactone to give 4-phenyl-7-diethylamino-4'-dimethylamino-1-benzopyrylium was observed upon irradiation of the system with UV light, erasing the thermochromic effect.

Ventura, MG, Laia CAT, Parola AJ.  2010.  Formation of Eu(III) Nanoparticles on Borosilicate Sol-Gel Studied with Time-Resolved Luminescence Techniques, 2010. Journal of Physical Chemistry C. 114:18414-18422. AbstractWebsite

The formation of Eu(III) nanoparticles in borosilicate sol-gels and the glass formation heat treatment effect on those particles were studied using luminescence techniques. The presence of the particles was observed using transmission electron microscopy (TEM) images followed by analysis with energy dispersive X-ray spectroscopy (EDS). These experiments showed the presence of particles with a large quantity of europium and chlorine and only small amounts of oxygen with sizes ranging from 30 to 100 nm. Heat treatment at 400, 600, and 800 degrees C lead to glass samples in which those particles were no longer observed. Steady-state and time-resolved luminescence techniques allowed a detailed study of Eu(III) photophysics in sot-gel and glass samples. In sol-gel matrices, the (5)D(0) -> (7)F(0) transition is very weak, hinting at Eu(III) species experiencing a rather symmetric crystal field. The (5)D(0) -> (7)F(2) transition intensity is not very strong, which according to a Judd-Ofelt analysis indicates low interaction with the anions present in the sol-gel matrices. This picture reverses after heat treatment, indicating a replacement of chloride anions with oxygen as preferential ligands of Eu(III). Time-resolved luminescence shows in a more detailed way these aspects. Sol-gel samples display nonexponential kinetics, which are attributed to Eu(III) species present in the nanoparticles surface (bound to oxygen) and Eu(III) in the core of the nanoparticles (bound to chloride). Glass samples display single-exponential luminescence decays, in which the decay constant approaches the values calculated for the radiative rate constant with Judd-Ofelt analysis. It is concluded that, in sol-gel, mechanisms like electron-phonon coupling suppress the Eu(III) luminescence, which disappear as soon as the nanoparticles are disrupted after heat treatment.

Leydet, Y, Parola AJ, Pina F.  2010.  Hydroxypyridinechromene and Pyridinechalcone: Two Coupled Photochromic Systems, 2010. Chemistry-a European Journal. 16:545-555. AbstractWebsite

Substitution of the phenyl group in 2-hydroxychalcones by a 4-pyridine unit dramatically changes the network of chemical reactions of this compound: trans-chalcone-type (Ct), cis-chalcone-type (Cc), and a hemiketal (hydroxy-4-pyridinechromene) (B) and their protonated forms are formed, but the presence of a flavylium-type cation could not be detected even at very acidic pH Values. Moreover, whereas in 2-phenyl-2-benzopyrylium compounds B and Cc are generally elusive species whose kinetic processes in aqueous solutions occur oil the sub-second time-scale, in the present compound these species equilibrate on a timescale four orders of magnitude lower. Complete characterization of the equilibrium and kinetics of the reaction network could thus be achieved by (1)H NMR spectroscopy and UV/Vis spectrophotometry. ne network of chemical reactions exhibits cis-trans photoisomerization, as well as photochromism between the hemiketal and the chalcone-type species. The irradiation of Ct in MeOH/ H(2)O (1:1) at 365 nm produces B almost quantitatively through two Consecutive photochemical reactions: Ct -> Cc photoisomerization followed by Cc -> B photo ring Closure with a global quantum yield of 0.02. On the other hand, irradiation of B at 254 nm leads to it photostationary state composed by 80% Ct and 20%, B. with a quantum yield of 0.21.

Santos, TG, Vilaça P, dos Santos J, Quintino L, Rosado L.  2010.  Innovative eddy current probe for micro defects, 2010. 36th Annual Review of Progress in Quantitative Nondestructive Evaluation, QNDE. 1211:377-384., Kingston, RI Abstract
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Pinheiro, AV, Parola AJ, Baptista PV, Lima JC.  2010.  pH Effect on the Photochemistry of 4-Methylcoumarin Phosphate Esters: Caged-Phosphate Case Study, 2010. Journal of Physical Chemistry A. 114:12795-12803. AbstractWebsite

There are numerous reports of coumarin ester derivatives, in particular phosphate esters, as photocleavable cages in biological systems. Despite the comprehensive analysis of the photocleavage mechanism, studies of 4-methylcoumarin caged phosphates and/or nucleotides were always performed at constant pH. In this work. we present the study of the pH effect on the photochemistry of (7-diethylaminocoumarin-4-yl)methyl phosphate (DEACM-P). Fluorescence and photocleavage quantum yields, as well as the fluorescence decay times were measured as a function of the pH. It was found that the pH produces significant changes in the overall photochemical quantum yield of DEACM-P, and the observed changes are complementary to those obtained from the fluorescence quantum yield. Deprotonation of DEACM-HPO(4)(-) to yield DEACM -PO(4)(2-), produces a decrease in the photochemical quantum yield (from 0.0045 to 0.0003) and an increase in the fluorescence quantum yield (from 0.072 to 0.092). Moreover, from the analysis of the decay times, we have also found that hydroxyl ion is not only relevant, but it is mechanistically involved in the photoreaction of DEACM-HPO(4)(-).

Rosado, LS, Ramos PM, Piedade M, Santos TG, Vilaça P.  2010.  A reconfigurable digital signal processing system for eddy currents non-destructive testing, 2010. 2010 IEEE International Instrumentation and Measurement Technology Conference, I2MTC 2010. :1284-1289., Austin, TX Abstract
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Pereira, M, Leal CR, Parola AJ, Scheven UM.  2010.  Reversible Photorheology in Solutions of Cetyltrimethylammonium Bromide, Salicylic Acid, and trans-2,4,4 '-Trihydroxychalcone, 2010. Langmuir. 26:16715-16721. AbstractWebsite

We show photorheology in aqueous solutions of weakly entangled wormlike micelles prepared with cetyltrimethylammonium bromide (CTAB), salicylic acid (HSal), and dilute amounts of the photochromic multistate compound trans-2,4,4'-trihydroxychalcone (Ct). Different chemical species of Ct are associated with different colorations and propensities to reside within or outside CTAB micelles. A light-induced transfer between the intra- and intermicellar space is used to alter the mean length of wormlike micelles and hence the rheological properties of the fluid, studied in steady-state shear Bow and in dynamic rheological measurements. Light-induced changes of fluid rheology are reversible by a the relaxation process. at relaxation rates which depend on pH and which are consistent with photochromic reversion rates measured by UV-vis absorption spectroscopy. Parameterizing viscoelostic rheological states by their effective relaxation time tau(c) and corresponding response modulus G(c), we find the light and dark states of the system to fall onto a characteristic state curve defined by comparable experiments conducted without photosensitive components. These reference experiments were prepared with the same concentration of CTAB, but different concentrations of HSal or sodium salicylote (NaSal), and tested at different temperatures.

Branco, A, Pinheiro C, Fonseca J, Tedim J, Carneiro A, Parola AJ, Freire C, Pina F.  2010.  Solid-State Electrochromic Cells Based on M(salen) -Derived Electroactive Polymer Films, 2010. Electrochemical and Solid State Letters. 13:J114-J118. AbstractWebsite

A systematic study of the electrochromic (EC) behavior of electropolymerized poly[M(salen)] films (M = Ni, Cu, and Pd) was performed by spectroelectrochemistry. Color contrast between oxidized and reduced states, stability under square wave potential cycling, coloration efficiency, and switching rate were evaluated. Five polymers were selected to assemble solid-state EC cells in a symmetrical configuration (electrode/poly[M(salen)] film/opaque electrolyte/poly[M(salen)] film/electrode). The best EC performance was found for poly[Pd(3-Mesalen)], poly[1], with 38% of initial diffuse reflectance variation and loss of 50% after 6769 cycles. (C) 2010 The Electrochemical Society. [DOI: 10.1149/1.3457474] All rights reserved.

Barbosa, PC, Rodrigues LC, Silva MM, Smith MJ, Parola AJ, Pina F, Pinheiro C.  2010.  Solid-state electrochromic devices using pTMC/PEO blends as polymer electrolytes, 2010. Electrochimica Acta. 55:1495-1502. AbstractWebsite

Flexible, transparent and self-supporting electrolyte films based on poly(trimethylene carbonate)/poly(ethylene oxide) (p(TMC/PEO) interpenetrating networks doped with LiClO(4) were prepared by the solvent casting technique. These novel solid polymer electrolyte (SPE) systems were characterized by measurements of conductivity, cyclic voltammetry, differential scanning calorimetry and thermogravimetry. The incorporation of solid electrolytes as components of electrochromic devices can offer certain operational advantages in real-world applications. In this study, all-solid-state electrochromic cells were characterized, using Prussian blue (PB) and poly-(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT) as complementary electrochromic compounds on poly(ethyleneterphthalate) (PET) coated with indium tin oxide (ITO) as flexible electrodes. Assembled devices with PET/ITO/PB/SPE/PEDOT/ITO/PET "sandwich-like" structure were assembled and successfully cycled between light and dark blue, corresponding to the additive optical transitions for PB and PEDOT electrochromic layers. The cells required long cycle times (>600 s) to reach full color switch and have modest stability towards prolonged cycling tests. The use of short duration cycling permitted the observation of changes in the coloration-bleaching performance in cells with different electrolyte compositions. (C) 2009 Elsevier Ltd. All rights reserved.

Gomes, R, Albuquerque RQ, Pina F, Parola J, De Cola L.  2010.  Supramolecular host-guest flavylium-loaded zeolite L hybrid materials: network of reactions of encapsulated 7,4 '-dihydroxyflavylium, 2010. Photochemical & Photobiological Sciences. 9:991-995. AbstractWebsite

We report a spectroscopic study of the network of reactions of a flavylium dye encapsulated in the one-dimensional channels of zeolite L. The positively charged 7,4'-dihydroxyflavylium (AH(+)) is easily incorporated and remains stable in zeolite L channels. Once encapsulated, the flavylium exhibits a red shift in the excitation spectrum comparative to aqueous solutions. Moreover, contrary to the observed behavior in water, no excited state proton transfer takes place in the loaded crystals, corroborating the encapsulation of AH(+). The trans-chalcone (Ct) form from the same flavylium network could also be encapsulated inside the zeolite L, using toluene with 20% triethylamine as solvent and K(+) as counter ion of the negative framework of the zeolite. The encapsulation of Ct is confirmed by changes on the excitation spectrum and by a blue shift in the emission. The encapsulated Ct was shown to generate AH(+) when the Ct-loaded crystals were suspended in water, which proves that isomerization, tautomerization and dehydration reactions take place inside the zeolite L.

Pinheiro, AV, Conde J, Parola AJ, Lima JC, Baptista PV.  2010.  Use of cyclodextrins as scavengers of inhibitory photo-products in light controlled in vitro synthesis of RNA, 2010. Journal of Photochemistry and Photobiology a-Chemistry. 213:147-151. AbstractWebsite

We recently reported on the use of caged nucleotides to attain full control of enzymatic polymerization of RNA solely by light. In the absence of light no RNA formation was possible due to the efficient caging by the coumarin moiety: after irradiation, caged ATP was released with quantitative precision and RNA polymerization was resumed. As photolabile protecting group [7-(diethylamino)coumarin-4-yl]methyl] (DEACM) was used due to its high absorbance in the visible region of the spectrum, fast deprotection kinetics and absence of radical intermediates. However, the 7-diethylamino-4-hydroxymethylcoumarin photo-product (DEACM-OH) was shown to inhibit the transcription reaction for concentrations higher than 30 mu M [5]. This inhibition has been associated with poor water solubility, which is commonly dealt with via cumbersome chemical modifications of the protecting moiety. To overcome inhibition, we evaluated the use of molecular scavengers to sequester DEACM-OH formed after irradiation. Determination of association constants of coumarin with beta-cyclodextrins allowed the assessment of its capability to remove free coumarin molecules from solution. The influence of beta-cyclodextrin in transcription reaction was also assessed. Results show that beta-cyclodextrin can be successfully used as scavenger as it increases the DEACM-OH threshold concentration for inhibition, amplifying the efficiency of light controlled in vitro transcription. (C) 2010 Elsevier B.V. All rights reserved.

Araújo, T, Nunes N, Palma S, Gamboa H.  2010.  Alpha rhythm onset detector based on localized EEG sensor. Proceedings of ESBME & MEDICON 2010. , Greece
Bicho, A, Peça IN, Roque ACA, Cardoso MM.  2010.  Anti-CD8 conjugated nanoparticles to target mammalian cells expressing CD8. International Journal of Pharmaceutics. 399:80–86., Number 1-2 AbstractWebsite

This work aimed at the development of targeted drug delivery systems using nanoparticles fused with antibodies. The antibody anti-human {CD8} was coupled onto {PLGA} nanoparticles, and the ability of these particles to specifically target cells expressing {CD8} was studied. The obtained particles were found to be of spherical shape exhibiting a size between 350 and 600 nm. In vitro experiments with different cellular cultures {(TE671}, {CHO} and {HEK293)} using unmodified nanoparticles containing rhodamine have shown that particles were present on their surface within 48 h of incubation. In vitro tests using {anti-CD8} conjugated nanoparticles in {CHO} cell cultures indicated that all transfected cells which express {CD8} show these particles on their surface within 1h of incubation. These results demonstrated that, in a shorter time, the produced particles can target cells expressing {CD8} on their surface which offers the ability to reduce drug side effects. The antibody-coupled nanoparticles represent a promising approach to improve the efficacy of active targeting for lymphoblastic leukaemia therapy.

Conceição, A, Gamboa H, Palma S, Araújo T, Nunes N, Marinho D, Costa A, Silva A, Louro H.  2010.  Comparison between the standard average muscle activation with the use of snorkel and without snorkel in breaskstroke techinique. Book of Abstracts of the 7688 XIth International Symposium for Biomechanics and Medicine in Swimming. :59., Oslo
Pina, AS, Lowe CR, Roque ACA.  2010.  Comparison of Fluorescence Labelling Techniques for the Selection of Affinity Ligands from Solid-Phase Combinatorial Libraries. Separation Science and Technology. 45:2187–2193., Number 15 Abstract

This study reports the comparison of fluorimetric techniques (fluorescence microscopy and spectrofluorimetry on a 96-well format) for the on-bead screening of combinatorial libraries of affinity ligands for chromatographic separations. Two solid-phase libraries of synthetic ligands based on distinct scaffolds were synthesized by combinatorial chemistry. The libraries comprising ligands representing different hydrophobic/hydrophilic properties and sizes were tested for binding to randomly selected biomolecules (labelled with a fluorophore). Fluorescence microscopy was revealed to be a reliable and reproducible technique for the detection of lead ligands which strongly bound the target biomolecule. Results obtained by fluorescence intensity measurements in a 96-well format were less consistent, mainly due to challenges related with the accurate dispensing of the solid support.

Ferreira, L.  2010.  Construção de Edíficios Sustentáveis - Contribuição para a definição de um Processo Operativo. Faculdade de Ciências e Tecnologia. (Amado, Miguel, Ed.)., Lisbon Abstract

A presente Dissertação trata do tema da Construção Sustentável, dando especial enfoque aos Processos Operativos existentes e ao caminho a percorrer para a elaboração de um Processo Operativo enquadrado especificamente dentro dos princípios da Construção Sustentável. Através de uma revisão bibliográfica, procedeu-se ao resumo da evolução dos métodos, técnicas, materiais e fins da construção, desde o início da Humanidade até à actualidade. Apresentou-se, de seguida, o enquadramento geral da realidade nacional e internacional no que respeita à construção de edifícios sustentáveis, tendo em conta as novas premissas para a construção, os novos métodos e os novos processos associados à Construção Sustentável. Neste âmbito, foram analisadas as soluções legislativas vigentes e as propostas analíticas de diversas entidades que se debruçam sobre este tema da Construção Sustentável, enquanto vertente especializada da problemática mais abrangente intrínseca ao aperfeiçoamento e aplicação do conceito de Desenvolvimento Sustentável. Este estudo, integrando uma observação profunda do ciclo de vida do edifício e das especificidades de cada uma das fases que o integram, permitiu cumprir o já referido objectivo primordial da presente Dissertação, contribuindo para o estudo, análise e elaboração de um modelo de investigação que permita avaliar ou elaborar um Processo Operativo para a Construção Sustentável. Desta forma, a presente Dissertação representa um avanço no desenvolvimento de um Processo Operativo para a Construção Sustentável adaptado à realidade da construção em Portugal.

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