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2011
Ortigueira, MD.  2011.  The Fractional Quantum Derivative and the Fractional Linear Scale Invariant Systems. Fractional Calculus for Scientists and Engineers. 84:123–144.: Springer-Verlag Abstract

The normal way of introducing the notion of derivative is by means of the limit of an incremental ratio that can assume three forms, depending the used translations as we saw in Chaps. 1 and 4. On the other hand, in those derivatives the limit operation is done over a set of points uniformly spaced: a linear scale was used. Here we present an alternative derivative, that is valid only for t {\ensuremath{>}} 0 or t {\ensuremath{<}} 0 and uses an exponential scale

Freitas, F, Alves VD, Torres CAV, Cruz M, Sousa I, Melo MJ, Ramos AM, Reis MAM.  2011.  Fucose-containing exopolysaccharide produced by the newly isolated Enterobacter strain A47 DSM 23139. Carbohydrate Polymers. 83:159-165., Number 1 AbstractWebsite
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2010
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
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.

"D.P.L. Silva", "R.F. Martins", BF""FM.  2010.  Finite Element Modelling of Ni-Ti Shape Memory Alloys. Materials Science Forum. 636-637:1112-1118.2010-finite_element_modelling_of_ni-ti_shape_memory_alloys.pdf
and D.P.L. Silva, MFRFFMB.  2010.  Finite element modelling of NiTi shape memory alloys. Materials Science Forum. 636-637:1112-1118.2010-finite_element_modelling_of_ni-ti_shape_memory_alloys.pdf
Matos, C, Ortigueira MD.  2010.  Fractional Filters: An Optimization Approach. Emerging Trends in Technological Innovation. 314:361–366. Abstract

The design and optimization of fractional filters is considered in this paper. Some of the classic filter architectures are presented and their performances relatively to an ideal amplitude spectrum evaluated. The fractional filters are designed using the differential evolution optimization algorithm for computing their parameters. To evaluate the performances of all the filters the quadratic error between the computed amplitude is calculated against an ideal (goal) response. The fractional filters have a better behavior, both in the pass and reject-band.

Ribeiro, T, Santos-Silva T, Alves VD, Dias FMV, Luis AS, Prates JAM, Ferreira LMA, Romao MJ, Fontes CMGA.  2010.  Family 42 carbohydrate-binding modules display multiple arabinoxylan-binding interfaces presenting different ligand affinities. Biochimica Et Biophysica Acta-Proteins and Proteomics. 1804:2054-2062., Number 10 AbstractWebsite
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Matos, C, Ortigueira MD.  2010.  Fractional Filters: An Optimization Approach. Emerging Trends in Technological Innovation. 314:361–366. Abstract

The design and optimization of fractional filters is considered in this paper. Some of the classic filter architectures are presented and their performances relatively to an ideal amplitude spectrum evaluated. The fractional filters are designed using the differential evolution optimization algorithm for computing their parameters. To evaluate the performances of all the filters the quadratic error between the computed amplitude is calculated against an ideal (goal) response. The fractional filters have a better behavior, both in the pass and reject-band.

Ortigueira, MD.  2010.  The fractional quantum derivative and its integral representations? Communications in Nonlinear Science and Numerical Simulation. 15:956–962., Number 4: Elsevier B.V. AbstractWebsite

The quantum fractional derivative is defined using formulations analogue to the common Grünwald?Letnikov derivatives. While these use a linear variable scale, the quantum derivative uses an exponential scale and is defined in R? or R?. Two integral formulations similar to the usual Liouville derivatives are deduced with the help of the Mellin transform.

2009
Moniz, AB.  2009.  Foresight studies on work in the knowledge society: a 2nd international conference at UNL, November. Enterprise and Work Innovation Studies. 5:77-81., Number 5 AbstractWebsite

The 2nd International Conference on "Foresight Studies on Work in the Knowledge Society" was organised by IET, the Research Centre on Enterprise and Work Innovation, at the Faculty of Sciences and Technology of "Universidade Nova de Lisboa" (FCT-UNL), and took place on January 26 and 27 of 2009 with the support of the European project WORKS-Work Organisation Re-structuring in the Knowledge Society (financed by the European Commission, and co-ordinated by HIVA Leuven)

Petrov, V, Gomes R, Parola AJ, Pina F.  2009.  Flash photolysis and stopped flow studies of the 2'-methoxyflavylium network in aq. acidic and alkaline solution, 2009. Dyes and Pigments. 80:149-155. AbstractWebsite

The rate and equilibrium constants of the network of chemical species involving the dye 2'-methoxyflavylium tetrafluoroborate were characterized using stopped flow and flash photolysis in both acidic and alkaline aqueous solution. The trans-chalcone is the thermodynamic stable species in acidic solutions 2 < pH < 7; irradiation of trans-chalcone at low pH leads to the corresponding coloured flavylium cation. The system reverts to its initial state in a few hours, in the dark. The kinetics of the various steps in the system were determined; flash photolysis revealed that the rate determining process of flavylium formation is the ring closure to give the corresponding hemiketal. In alkaline medium the ionized transchalcone is the stable form and clear evidence for the existence of a hemiketal species was obtained. A write-read-erase cycle can be performed with this compound. (c) 2008 Elsevier Ltd. All rights reserved.

Matos, C, Batista AG, Ortigueira MD.  2009.  FILTERS: Fractional vs Integer order. Symposium on Fractional Signals and Systems, Lisbon?09. Abstract

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Ortigueira, MD.  2009.  Fractional Derivatives and Linear Systems. Mobile Computing Research and Applications. :219-269.: Nova Science Publishers, Inc Abstract

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Leal, A, Monteiro J, Secca MF, Jordão C.  2009.  Functional brain mapping of ictal activity in gelastic epilepsy associated with hypothalamic hamartoma: A case report. Epilepsia. 50(6):1624-1631.
Matos, C, Batista AG, Ortigueira MD.  2009.  FILTERS: Fractional vs Integer order. Symposium on Fractional Signals and Systems, Lisbon?09. Abstract
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Ortigueira, MD.  2009.  Fractional Derivatives and Linear Systems. Mobile Computing Research and Applications. :219–269.: Nova Science Publishers, Inc. Abstract
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2008
Paulos, MR, Moniz AB.  2008.  Fragmentation? The future of work in Europe in a global economy: the WORKS final International Conference debate, November Enterprise and Work Innovation Studies. 4:167-169., Number 4 AbstractWebsite

WORKS final conference report

Moniz, A, Paulos MR.  2008.  Futures of automobile industry and challenges on sustainable development and mobility, May. , Number 9022: University Library of Munich, Germany Abstract

Portugal had only very few foresight exercises on the automobile sector, and the most recent one was a survey held in a project on work organisation systems in the automobile industry, its recent historical paths and the special strategies of location of companies (the WorTiS project). This involved several teams with different disciplinary backgrounds and from two Portuguese universities. The provisional main results of the first round of a Delphi survey held in Portugal on the automotive sector were already published, but a further analysis was not yet done. This foresight survey was done under the WorTiS project, developed in 2004 by IET – Research Centre on Enterprise and Work Innovation (at FCT-UNL), and financed by the Portuguese Ministry of Science and Technology. Some of this experience on foresight analysis is also been transferred to other projects, namely the WORKS project on work organisation restructuring in the knowledge society that received the support from EC and still is running. The majority of experts considered having an average of less knowledge in almost all the scenario topics presented. This means that information on the automotive industry is not spread enough among academics or experts in related fields (regional scientists, innovation economists, engineers, sociologists). Some have a good knowledge but in very specialised fields. Others have expertise on foresight, or macroeconomics, or management sciences, but feel insecure on issues related with futures of automobile sector. Nevertheless, we considered specially the topics where the experts considered themselves to have some knowledge. There were no “irrelevant” topics considered as such by the expert panel. There are also no topics that are not considered a need for co-operation. The lack of technological infrastructures was not considered as a hindered factor for the accomplishment of any scenario. The experts’ panel considered no other international competence besides US, Jap

Moniz, AB, Paulos M.  2008.  Futures of automobile industry and challenges on sustainable development and mobility, May. , Number hal-00287886: HAL Abstract

Portugal had only very few foresight exercises on the automobile sector, and the most recent one was a survey held in a project on work organisation systems in the automobile industry, its recent historical paths and the special strategies of location of companies (the WorTiS project). This involved several teams with different disciplinary backgrounds and from two Portuguese universities. The provisional main results of the first round of a Delphi survey held in Portugal on the automotive sector were already published, but a further analysis was not yet done. This foresight survey was done under the WorTiS project, developed in 2004 by IET – Research Centre on Enterprise and Work Innovation (at FCT-UNL), and financed by the Portuguese Ministry of Science and Technology. Some of this experience on foresight analysis is also been transferred to other projects, namely the WORKS project on work organisation restructuring in the knowledge society that received the support from EC and still is running. The majority of experts considered having an average of less knowledge in almost all the scenario topics presented. This means that information on the automotive industry is not spread enough among academics or experts in related fields (regional scientists, innovation economists, engineers, sociologists). Some have a good knowledge but in very specialised fields. Others have expertise on foresight, or macroeconomics, or management sciences, but feel insecure on issues related with futures of automobile sector. Nevertheless, we considered specially the topics where the experts considered themselves to have some knowledge. There were no “irrelevant” topics considered as such by the expert panel. There are also no topics that are not considered a need for co-operation. The lack of technological infrastructures was not considered as a hindered factor for the accomplishment of any scenario. The experts’ panel considered no other international competence besides US, Japan

Moniz, AB, Paulos MR.  2008.  Futures of automobile industry and challenges on sustainable development and mobility, Apr. , Number 04/2008: Universidade Nova de Lisboa, IET-Research on Enterprise and Work Innovation, Faculty of Science and Technology Abstract

Portugal had only very few foresight exercises on the automobile sector, and the most recent one was a survey held in a project on work organisation systems in the automobile industry, its recent historical paths and the special strategies of location of companies (the WorTiS project). This involved several teams with different disciplinary backgrounds and from two Portuguese universities. The provisional main results of the first round of a Delphi survey held in Portugal on the automotive sector were already published, but a further analysis was not yet done. This foresight survey was done under the WorTiS project, developed in 2004 by IET – Research Centre on Enterprise and Work Innovation (at FCT-UNL), and financed by the Portuguese Ministry of Science and Technology. Some of this experience on foresight analysis is also been transferred to other projects, namely the WORKS project on work organisation restructuring in the knowledge society that received the support from EC and still is running. The majority of experts considered having an average of less knowledge in almost all the scenario topics presented. This means that information on the automotive industry is not spread enough among academics or experts in related fields (regional scientists, innovation economists, engineers, sociologists). Some have a good knowledge but in very specialised fields. Others have expertise on foresight, or macroeconomics, or management sciences, but feel insecure on issues related with futures of automobile sector. Nevertheless, we considered specially the topics where the experts considered themselves to have some knowledge. There were no “irrelevant” topics considered as such by the expert panel. There are also no topics that are not considered a need for co-operation. The lack of technological infrastructures was not considered as a hindered factor for the accomplishment of any scenario. The experts’ panel considered no other international competence besides US, Jap

Sousa, MM, Melo MJ, Parola AJ, de Melo JSS, Catarino F, Pina F, Cook FEM, Simmonds MSJ, Lopes JA.  2008.  Flavylium chromophores as species markers for dragon's blood resins from Dracaena and Daemonorops trees, 2008. Journal of Chromatography A. 1209:153-161. AbstractWebsite

A simple and rapid liquid chromatographic method with diode-array UV-vis spectrophotometric detection has been developed for the authentication of dragon's blood resins from Dracaena and Daemonorops trees. Using this method it was discovered that the flavylium chromophores, which contribute to the red colour of these resins, differ among the species and could be used as markers to differentiate among species. A study of parameters, such as time of extraction, proportion of MeOH and pH, was undertaken to optimise the extraction of the flavyliums. This method was then used to make extracts from samples of dragon's blood resin obtained from material of known provenance. From the samples analysed 7,6-dihydroxy-5-methoxyflavylium (dracorhodin), 7,4'-dihydroxy-5-methoxyflavylium (dracoflavylium) and 7,4'-dihydroxyflavylium were selected as species markers for Daemonorops spp., Dracaena draco and Dracaena cinnabari, respectively. The chromatograms from these samples were used to build an HPLC-DAD database. The ability to discriminate among species of dragon's blood using the single marker compounds was compared with a principal components analysis of the chromatograms in the HPLC-DAD database. The results from the HPLC-DAD method based on the presence of these flavylium markers was unequivocal. The HPLC-DAD method was subsequently applied to 37 samples of dragon blood resins from the historical samples in the Economic Botany Collection, Royal Botanic Gardens, Kew. The method identified anomalies in how samples in this collection had been labelled. It is clear that the method can be used to evaluate the provenance of samples used in different areas of cultural heritage. It also could be used to monitor the trade of endangered species of dragon's blood and the species being used in complex formulations of traditional Chinese medicine. (C) 2008 Elsevier B.V. All rights reserved.

Coito, F, Ortigueira M.  2008.  Fractional Controller Design Trough Multi-Objective Optimization. 8th Portuguese Conference on Automatic Control ? CONTROLO?2008. Abstract

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Ortigueira, M.  2008.  The Fractional Quantum Derivative and the Fractional Linear Scale Invariant Systems. 3rd IFAC Workshop on Fractional Differentiation and its Applications. Abstract

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