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2011
da Silva, MS, Nobrega FL, Aguiar-Ricardo A, Cabrita EJ, Casimiro T.  2011.  Development of molecularly imprinted co-polymeric devices for controlled delivery of flufenamic acid using supercritical fluid technology. The Journal of Supercritical Fluids. 58:150-157., Number 1 AbstractWebsite

This work reports the development of a novel class of affinity co-polymeric materials using supercritical fluid technology. Polymeric materials with molecular recognition to flufenamic acid, were first synthesized in supercritical carbon dioxide (scCO2) using the drug as template. Molecularly imprinted co-polymers of methacrylic acid (MAA) or N-isopropyl acrylamide (NIPAAm) crosslinked with ethylene glycol dimethacrylate (EGDMA) were synthesized using different crosslinking degrees and template:monomer ratios, at 65 °C and 21 MPa. High-pressure \{NMR\} experiments confirmed that the nature of the interactions between the drug and the functional monomers during the polymerization step are mainly hydrogen bonds. scCO2-assisted impregnation revealed that the imprinted matrices were able to uptake higher amounts of flufenamic acid. This effect was particularly evidenced in the more crosslinked matrices, with P(MAA–EGDMA) imprinted copolymers binding up to 101.5 mg drug/g polymer against only 50.5 mg/g in the non-imprinted copolymer. In vitro drug delivery experiments showed that imprinted co-polymers release the drug in a more sustained way than the corresponding non-imprinted matrices. Overall it was shown that supercritical fluid technology is a viable approach for the development of self-assembly molecular recognition polymers with potential application in controlled drug delivery systems.

2010
Moniz, AB.  2010.  Designing a Technology Assessment post-graduation programme: experiences, limits and needs, Sep. , Number 09/2010: Universidade Nova de Lisboa, IET-Research on Enterprise and Work Innovation, Faculty of Science and Technology Abstract

The post-graduation in the field of Technology Assessment (TA) is recent and that are several and different ways to be organised. Most experiences are related with the Masters diplom level (2nd cycle of graduation in high education). Just one in PhD level is explicit in the field of TA, and some other PhD courses include also TA topics in their programme structure. In this chapter we will analyse the problems related with the design of a post-graduation (MA, MSc or PhD) programme in the field of TA using as reference some international experiences. Hereby, the main conclusion seems to address labour market needs in the specialised knowledge of TA, of technology management or technology innovation. In this sense TA should be included as “minor” into post-graduation courses which may range from engineering disciplines to social sciences. As a graduation programme it can fill an expertise gap between technicians,engineers, scientists and the strategic decision makers or policy makers.

Raimundo, J, Costa PM, Vale C, Costa MH, Moura I.  2010.  DNA damage and metal accumulation in four tissues of feral Octopus vulgaris from two coastal areas in Portugal, Oct. Ecotoxicology and Environmental Safety. 73:1543-1547., Number 7 AbstractWebsite

The alkaline comet assay has been employed for the first time to estimate the basal DNA damage in the digestive gland, gills, kidney and gonads of Octopus vulgaris. Octopuses were captured in two coastal areas adjacent to the cities of Matosinhos (N) and Olhao (S), Portugal. The area of Matosinhos is influenced by discharges of the Douro River, city of Porto, industries and intensive agriculture, while Olhao is an important fisheries port. Previous works point to contrasting metal availability in the two coastal areas. Among the analysed tissues digestive gland presented the highest levels of Zn, Cu, Cd and Pb. Tissues of specimens from Matosinhos exhibited high levels of Cd and from Olhao enhanced Pb concentrations. The DNA damages in digestive gland, gills and kidney were more accentuated in specimens from Matosinhos than from Olhao, suggesting a stronger effect of contaminants. Elevated strand breakages were registered in digestive gland, recognised for its ability to store and detoxify accumulated metals. The DNA damages in kidney, gills and gonads were lower, reflecting reduced metal accumulation or efficient detoxification. The broad variability of damages in the three tissues may also mirror tissue function, specific defences to genotoxicants and cell-cycle turnover. (C) 2010 Elsevier Inc. All rights reserved.

Larguinho, M, Santos {HM }, c}alo Doria G{\c, Scholz H, Baptista {PV}, Capelo {JL }.  2010.  Development of a fast and efficient ultrasonic-based strategy for DNA fragmentation, may. Talanta. 81:881–886., Number 3: Elsevier Abstract

Several ultrasound-based platforms for DNA sample preparation were evaluated in terms of effective fragmentation of DNA (plasmid and genomic DNA)-ultrasonic probe, sonoreactor, ultrasonic bath and the newest Vialtweeter device. The sonoreactor showed the best efficiency of DNA fragmentation while simultaneously assuring no cross-contamination of samples, and was considered the best ultrasonic tool to achieve effective fragmentation of DNA at high-throughput and avoid sample overheating. Several operation variables were studied-ultrasonication time and amplitude, DNA concentration, sample volume and sample pre-treatment-that allowed optimisation of a sonoreactor-based strategy for effective DNA fragmentation. Optimal operating conditions to achieve DNA fragmentation were set to 100% ultrasonic amplitude, 100 μL sample volume, 8 min ultrasonic treatment (2 min/sample) for a DNA concentration of 100 μg mL-1. The proposed ultrasonication strategy can be easily implemented in any laboratory setup, providing fast, simple and reliable means for effective DNA sample preparation when fragmentation is critical for downstream molecular detection and diagnostics protocols.

Martins, {RFDP}, Baptista {PMRV}, Fortunato {EMC}.  2010.  Detection and quantification system of biological, matter constituted by one or more optical sensors and one or more light sources, associated process and related applications, feb. Abstract

The present invention relates to a system and process for detection and/or qualitative and quantitative identification of the biological material, such as specific sequences of nucleic acids or proteins as antibodies, present in biological samples. The system is composed by one or more light sources (1) combined with one or more integrated optical photo sensors, or not, and various electronic components (4), necessary for obtaining/processing of the signal emitted by the metal nanoprobes functionalized with a solution of biological composite, as well as also a micro-controller and a microprocessor, fixed or portable. This photosensor structure is able to detect and to quantify the colour variations produced by metal nanoprobes, being this preferentially gold, functionalized by oligonucleotides complementary to specific DNA/RNA sequences, proteins, as for instance antibodies and/or antigens related with certain disease, or other sample or solution of biological composite, that are to be investigated. The detection and quantification process is based on the response of a photosensor, singular or integrated, based on thin film technology of amorphous, nanocrystalline or microcrystalline silicon and their alloys, as well as the new active ceramic semiconductors, amorphous and not amorphous.

Affouard, F, Correia NT.  2010.  Debye Process in Ibuprofen Glass-Forming Liquid: Insights from Molecular Dynamics Simulation. The Journal of Physical Chemistry B. 114(35):11397–11402. AbstractWebsite

By means of molecular dynamics simulations, dynamical properties of racemic ibuprofen glass-forming liquid are investigated at different temperatures from 360 to 500 K. The origin of the peculiar low amplitude Debye-type relaxation observed experimentally by dielectric relaxation spectroscopy is addressed (Bras, A. R.; Noronha, J. P.; Antunes, A. M. M.; Cardoso, M. M.; Schönhals, A.; Affouard, F.; Dionisio, M.; Correia, N. T. J. Phys. Chem. B 2008, 112, 11087). Single and total dipolar autocorrelation functions are calculated. It is found that the behavior of the total dipole correlation is dominated at short and long times by the single function. It mainly originates from the antiparallel dipoles correlations in agreement with a value of the Kirkwood correlation factor slightly smaller than unity. The simulation suggests that the long time Debye-type decay of the dipole−dipole correlation is dominated by the internal cis−trans conversion of the O═C—O—H group coupled to the change of the intermolecular linear/cyclic HB structures. The overall rotation of the molecules is about 1−2 decades faster than the cis to trans transformation, so all the O═C—O—H group environments are equal on average. The effective rotational potential energy barriers of the O═C—O—H groups due to the surroundings are thus averaged and dipolar relaxation follows a simple Debye law. It is found that cyclic dimers inhibit the cis to trans conversion unlike the linear dimers and trimers which favor this conversion and stabilize the trans isomer. It is well in line with the very low amplitude of the dielectric strength associated with the Debye relaxation observed experimentally and its increase when the liquid is maintained isothermally above the melting temperature since this amplitude mainly relates to the low fraction of ibuprofen molecules in the trans conformation. A comparison is made with the Debye-type relaxation found in microstructured monohydroxy alcohols.

Araújo, T.  2010.  Desenvolvimento de um sensor de electroencefalografia localizado. FCT. , Lisboa: UNL
Sousa, M, Brás AR, Veiga HIM, Ferreira CF, Pinho MN, Correia NT, Dionísio M.  2010.  Dynamical Characterization of a Cellulose Acetate Polysaccharide. The Journal of Physical Chemistry B. 114:10939-10953.Website
Rondao, R, Seixas de Melo SJ, Bonifacio VDB, Melo MJ.  2010.  Dehydroindigo, the Forgotten Indigo and Its Contribution to the Color of Maya Blue. Journal of Physical Chemistry A. 114:1699-1708., Number 4 AbstractWebsite
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Kundu, S, Feio G, Pinto LFV, Almeida PL, Figueirinhas JL, Godinho MH.  2010.  Deuterium NMR Study of Orientational Order in Cellulosic Network Microfibers. Macromolecules. 43:5749-5755., Number 13 AbstractWebsite

Deuterium NMR was used to investigate the orientational order in a composite cellulosic formed by liquid crystalline acetoxypropylcellulose (A PC) and demented nematic 4'-penty1-4-cyanobiphenyl (5CB-4 alpha d(2)) with the per centage of 85% A PC by weight Three forms of the composite including electro spun microfibers, thin film and bulk samples were analyzed The NMR results initially suggest two distinct scenarios, one whet e the 503-alpha d(2), is confined to small droplets with dimensions smaller than the magnetic coherence length and the other where the 503-alpha d(2) molecules arc aligned with the A PC network chains Polarized optical microscopy (POW from thin film samples along with all the NMR results show the presence of 5CB-alpha d(2) droplets in the composite systems with a nematic wetting layer at the APC-5CB-alpha d(2) interface that experiences and order disorder transition driven by the polymer network N-I transition The characterization of the APC network I-N transition shows a pronounced subcritical behavior within a heterogeneity scenario

2009
Ramos, S, Duarte RO, Moura JJ, Aureliano M.  2009.  Decavanadate interactions with actin: cysteine oxidation and vanadyl formation, Oct 14. Dalton Trans. :7985-94., Number 38 AbstractWebsite

Incubation of actin with decavanadate induces cysteine oxidation and oxidovanadium(IV) formation. The studies were performed combining kinetic with spectroscopic (NMR and EPR) methodologies. Although decavanadate is converted to labile oxovanadates, the rate of deoligomerization can be very slow (half-life time of 5.4 h, at 25 degrees C, with a first order kinetics), which effectively allows decavanadate to exist for some time under experimental conditions. It was observed that decavanadate inhibits F-actin-stimulated myosin ATPase activity with an IC(50) of 0.8 microM V(10) species, whereas 50 microM of vanadate or oxidovanadium(IV) only inhibits enzyme activity up to 25%. Moreover, from these three vanadium forms, only decavanadate induces the oxidation of the so called "fast" cysteines (or exposed cysteine, Cys-374) when the enzyme is in the polymerized and active form, F-actin, with an IC(50) of 1 microM V(10) species. Decavanadate exposition to F- and G-actin (monomeric form) promotes vanadate reduction since a typical EPR oxidovanadium(IV) spectrum was observed. Upon observation that V(10) reduces to oxidovanadium(IV), it is proposed that this cation interacts with G-actin (K(d) of 7.48 +/- 1.11 microM), and with F-actin (K(d) = 43.05 +/- 5.34 microM) with 1:1 and 4:1 stoichiometries, respectively, as observed by EPR upon protein titration with oxidovanadium(IV). The interaction of oxidovanadium(IV) with the protein may occur close to the ATP binding site of actin, eventually with lysine-336 and 3 water molecules.

Martins, {RFDP}, Baptista {PMRV}, Fortunato {EMC}.  2009.  Detection and quantification system of biological matter constituted by one or more optical sensors and one or more light sources, associated process and related applications, may. Abstract

The present invention relates to a system and process for detection and/or qualitative and quantitative identification of the biological material, such as specific sequences of nucleic acids or proteins as antibodies, present in biological samples. The system is composed by one or more light sources (1) combined with one or more integrated optical photo sensors, or not, and various electronic components (4), necessary for obtaining/ processing of the signal emitted by the metal nanoprobes functionalized with a solution of biological composite, as well as also a micro-controller and a microprocessor, fixed or portable. This photosensor structure is able to detect and to quantify the colour variations produced by metal nanoprobes, being this preferentially gold, functionalized by oligonucleotides complementary to specific DNA/RNA sequences, proteins, as for instance antibodies and/or antigens related with certain disease, or other sample or solution of biological composite, that are to be investigated. The detection and quantification process is based on the response of a photosensor, singular or integrated, based on thin film technology of amorphous, nanocrystalline or microcrystalline silicon and their alloys, as well as the new active ceramic semiconductors, amorphous and not amorphous.

Temtem, M, Pompeu D, Jaraquemada G, Cabrita EJ, Casimiro T, Aguiar-Ricardo A.  2009.  Development of PMMA membranes functionalized with hydroxypropyl-beta-cyclodextrins for controlled drug delivery using a supercritical CO(2)-assisted technology, JUL 6 2009. International Journal of Pharmaceutics. 376:110-115., Number 1-2 Abstract

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Duarte, FJS, Cabrita EJ, Frenking G, Santos GA.  2009.  Density Functional Study of Proline-Catalyzed Intramolecular Baylis-Hillman Reactions, 2009. Chemistry-a European Journal. 15:1734-1746., Number 7 Abstract

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Santos, T, Vilaça P, Quintino L.  2009.  Developments in NDT for detecting imperfections in friction stir welds in aluminium alloys, 2009. Rivista Italiana della Saldatura. 61(1):65-72. AbstractWebsite
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Ribeiro, MP, Espiga A, Silva D, Baptista P, Henriques J, Ferreira C, Silva JC, Borges JP, Pires E, Chaves P, Correia IJ.  2009.  Development of a new chitosan hydrogel for wound dressing. Wound repair and regeneration. 17(6):817–824., Number 6: Blackwell Publishing Inc AbstractWebsite

Wound healing is a complex process involving an integrated response by many different cell types and growth factors in order to achieve rapid restoration of skin architecture and function. The present study evaluated the applicability of a chitosan hydrogel (CH) as a wound dressing. Scanning electron microscopy analysis was used to characterize CH morphology. Fibroblast cells isolated from rat skin were used to assess the cytotoxicity of the hydrogel. CH was able to promote cell adhesion and proliferation. Cell viability studies showed that the hydrogel and its degradation by-products are noncytotoxic. The evaluation of the applicability of CH in the treatment of dermal burns in Wistar rats was performed by induction of full-thickness transcutaneous dermal wounds. Wound healing was monitored through macroscopic and histological analysis. From macroscopic analysis, the wound beds of the animals treated with CH were considerably smaller than those of the controls. Histological analysis revealed lack of a reactive or a granulomatous inflammatory reaction in skin lesions with CH and the absence of pathological abnormalities in the organs obtained by necropsy, which supported the local and systemic histocompatibility of the biomaterial. The present results suggest that this biomaterial may aid the re-establishment of skin architecture.

Feio, G, Figueirinhas JL, Tajbakhsh AR, Terentjev EM.  2009.  Deuterium NMR study of mobility and fluctuations in nematic and isotropic elastomers. J Chem Phys. 131:074903., Number 7 AbstractWebsite

Orientational ordering in polydomain nematic and isotropic elastomers with identical polysiloxane backbone and different deuterium-labeled side groups is studied by D-NMR. In the nematic elastomer the orientational order parameter grows in a critical fashion on crossing the I-N transition implying a continuous phase transition driven by critical fluctuations of local director. The orientational (nematic) ordering occurs on the background of the polymer dynamics exhibited by the backbone, which is similar in the nematic and the analogous isotropic elastomers. The temperature dependence of NMR linewidths is compatible with a Vogel-Fulcher glassy dynamics.

2008
Barreiros, D.  2008.  Detecção e análise do Potencial Evocado P300, November. (Manuel Ortigueira, Ed.).: FCT-UNL Abstract
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Cordas, CM, Moura I, Moura JJ.  2008.  Direct electrochemical study of the multiple redox centers of hydrogenase from Desulfovibrio gigas, Nov. Bioelectrochemistry. 74:83-9., Number 1 AbstractWebsite

Direct electrochemical response was first time observed for the redox centers of Desulfovibrio gigas [NiFe]-Hase, in non-turnover conditions, by cyclic voltammetry, in solution at glassy carbon electrode. The activation of the enzyme was achieved by reduction with H(2) and by electrochemical control and electrocatalytic activity was observed. The inactivation of the [NiFe]-Hase was also attained through potential control. All electrochemical data was obtained in the absence of enzyme inhibitors. The results are discussed in the context of the proposed mechanism currently accepted for activation/inactivation of [NiFe]-Hases.

Martins, {RFDP}, Baptista {PMRV}, Fortunato {EMC}.  2008.  Detection and quantification system of biological matter constituted by one or more optical sensors and one or more light sources, associated process and related applications, mar. Abstract

The present invention relates to a system and process for detection and/or qualitative and quantitative identification of the biological material, such as specific sequences of nucleic acids or proteins as antibodies, present in biological samples. The system is composed by one or more light sources (1) combined with one or more integrated optical photo sensors, or not, and various electronic components (4), necessary for obtaining/ processing of the signal emitted by the metal nanoprobes functionalized with a solution of biological composite, as well as also a micro-controller and a microprocessor, fixed or portable. This photosensor structure is able to detect and to quantify the colour variations produced by metal nanoprobes, being this preferentially gold, functionalized by oligonucleotides complementary to specific DNA/RNA sequences, proteins, as for instance antibodies and/or antigens related with certain disease, or other sample or solution of biological composite, that are to be investigated. The detection and quantification process is based on the response of a photosensor, singular or integrated, based on thin film technology of amorphous, nanocrystalline or microcrystalline silicon and their alloys, as well as the new active ceramic semiconductors, amorphous and not amorphous.

Dos Santos, TG, Silva BS, Dos Santos Vilaça P, Quintino L, Sousa JMC.  2008.  Data fusion in non destructive testing using fuzzy logic to evaluate friction stir welding, 2008. Welding International. 22(12):826-833.: Taylor and Francis Ltd. AbstractWebsite
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Santos, T, Vilaça P, Quintino L.  2008.  Developments in NDT for detecting imperfections in friction stir welds in aluminium alloys, 2008. Welding in the World. 52(9-10):30-37. AbstractWebsite
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Palma, LB, Gil PS, Coito FV, Duarte-Ramos H.  2008.  Dealing with Complexity in Supervision Systems. Abstract

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Cardoso, M, Figueirinhas JL, Cruz C, Van-Quynh A, Ribeiro AC, Feio G, Apreutesei D, Mehl GH.  2008.  Deuterium NMR Investigation of the Influence of Molecular Structure on the Biaxial Ordering of Organosiloxane Tetrapodes Nematic Phase. Molecular Crystals and Liquid Crystals. 495:700-+. AbstractWebsite

In order to contribute to the understanding of the origin of biaxial nematic ordering in tetrapodes, a deuterium NMR study was performed on mixtures of monomers from organosiloxane tetrapodes with a deuterated nematic probe. Contrary to the tetrapode system previously studied, which exhibits a biaxial nematic phase, the results for monomers are compatible, within the experimental error, with uniaxial nematic ordering in the whole nematic range. The data are in agreement with the conjecture that the nematic biaxial behaviour is related to hindering of the mesogenic units' rotational movements, arising from interdigitation and connection to the central silicon core.

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