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2012
Amaral, A., P. Brogueira, O. Conde, G. Lavareda, and C. Nunes de Carvalho. "Device quality InOx:Sn and InOx thin films deposited at room temperature with different rf-power densities." THIN SOLID FILMS. 526 (2012): 221-224. Abstract

The influence of tin doping on the electrical, optical, structural and morphological properties of indium oxide films produced by radio-frequency plasma enhanced reactive thermal evaporation is studied, as transport properties are expected to improve with doping. Undoped and tin doped indium oxide thin films are deposited at room temperature using both pure In rods and (95-80) % In:(5-20) % Sn alloys as evaporation sources and 19.5 mW/cm(2) and 58.6 mW/cm(2) as rf-power densities. The two most important macroscopic properties - visible transparency and electrical resistivity - are relatively independent of tin content (0-20%). Visible transmittance of about 75% and electrical resistivity around 5 x 10(-4) Omega.cm can be observed in the films. The structural features are similar for all samples. Nevertheless, the surface morphology characterization shows that the homogeneity of the films varies according to the tin content. Moreover this variation is a balance between the rf-power and the tin content in the alloy: i) films with small and compact grains are produced at 58.6 mW/cm(2) from a 5% Sn alloy or at 19.5 mW/cm(2) from a 15% Sn alloy and consequently, smooth surfaces with reduced roughness and similar grain size and shape are obtained; ii) films showing the presence of aggregates randomly distributed above a tissue formed of thinner grains and higher roughness are produced at the other deposition conditions. (C) 2012 Elsevier B. V. All rights reserved.

Amaral, A., P. Brogueira, O. Conde, G. Lavareda, and C. Nunes de Carvalho. "Device quality InOx:Sn and InOx thin films deposited at room temperature with different rf-power densities." THIN SOLID FILMS. 526 (2012): 221-224. Abstract

The influence of tin doping on the electrical, optical, structural and morphological properties of indium oxide films produced by radio-frequency plasma enhanced reactive thermal evaporation is studied, as transport properties are expected to improve with doping. Undoped and tin doped indium oxide thin films are deposited at room temperature using both pure In rods and (95-80) % In:(5-20) % Sn alloys as evaporation sources and 19.5 mW/cm(2) and 58.6 mW/cm(2) as rf-power densities. The two most important macroscopic properties - visible transparency and electrical resistivity - are relatively independent of tin content (0-20%). Visible transmittance of about 75% and electrical resistivity around 5 x 10(-4) Omega.cm can be observed in the films. The structural features are similar for all samples. Nevertheless, the surface morphology characterization shows that the homogeneity of the films varies according to the tin content. Moreover this variation is a balance between the rf-power and the tin content in the alloy: i) films with small and compact grains are produced at 58.6 mW/cm(2) from a 5% Sn alloy or at 19.5 mW/cm(2) from a 15% Sn alloy and consequently, smooth surfaces with reduced roughness and similar grain size and shape are obtained; ii) films showing the presence of aggregates randomly distributed above a tissue formed of thinner grains and higher roughness are produced at the other deposition conditions. (C) 2012 Elsevier B. V. All rights reserved.

Lavareda, G., C. Nunes de Carvalho, A. M. Ferraria, A. M. Botelho Do Rego, and A. Amaral. "p-Type Cuo(X) Thin Films by rf-Plasma Enhanced Reactive Thermal Evaporation: Influence of rf-Power Density." JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY. 12 (2012): 6754-6757. Abstract

Copper oxide is a well known p-type semiconductor material, usually obtained by thermal oxidation of copper thin-films within few minutes, at atmospheric pressure. In this paper, thin films of copper oxide that were deposited by radio-frequency plasma enhanced reactive thermal evaporation of copper at room temperature, without any post-deposition annealing treatment, are studied. The deposition of good quality p-type semiconductor oxide to be used in the fabrication of p-TFTs is the purpose of this work. The thickness of the films varies from 97 up to 160 nm. The influence of rf power density on chemical, electrical and optical properties of the films was studied. Samples present conductivity within the range of 6 x 10(-5) to 4 x 10(2) Omega(-1) cm(-1) (thermal activation energy in the interval 0.46 to 0.01 eV). The p-type conductivity of the films was confirmed by Seebeck effect in the more conductive samples. Surface composition obtained by XPS analysis was correlated with optical and electrical properties, showing that rf-power plays a main role in changes of material characteristics.

Lavareda, G., C. Nunes de Carvalho, A. M. Ferraria, A. M. Botelho Do Rego, and A. Amaral. "p-Type Cuo(X) Thin Films by rf-Plasma Enhanced Reactive Thermal Evaporation: Influence of rf-Power Density." JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY. 12 (2012): 6754-6757. Abstract

Copper oxide is a well known p-type semiconductor material, usually obtained by thermal oxidation of copper thin-films within few minutes, at atmospheric pressure. In this paper, thin films of copper oxide that were deposited by radio-frequency plasma enhanced reactive thermal evaporation of copper at room temperature, without any post-deposition annealing treatment, are studied. The deposition of good quality p-type semiconductor oxide to be used in the fabrication of p-TFTs is the purpose of this work. The thickness of the films varies from 97 up to 160 nm. The influence of rf power density on chemical, electrical and optical properties of the films was studied. Samples present conductivity within the range of 6 x 10(-5) to 4 x 10(2) Omega(-1) cm(-1) (thermal activation energy in the interval 0.46 to 0.01 eV). The p-type conductivity of the films was confirmed by Seebeck effect in the more conductive samples. Surface composition obtained by XPS analysis was correlated with optical and electrical properties, showing that rf-power plays a main role in changes of material characteristics.

Zeballos, Luis J., Maria Isabel Gomes, Ana P. Barbosa-Povoa, and Augusto Q. Novais. "Addressing the uncertain quality and quantity of returns in closed-loop supply chains." Computers & Chemical Engineering. 47 (2012): 237-247. AbstractWebsite

In this work a two-stage scenario-based modeling approach is proposed in order to simultaneously deal with the design and planning decisions in supply chain networks, where both forward and reverse flows are considered (closed-loop supply chains) subject to uncertain conditions. A mixed integer linear programming (MILP) approach is developed with the underlying objective of profit maximization. Planning takes into account raw material acquisition and processing, storage and distribution of several products flowing through the network. Uncertainty is associated to the quantity and quality of the flow of products of the reverse network, which are directly affected by customers and sorting centers, respectively. The approach considers, by means of scenarios, the simultaneous integration of two important uncertainty sources, thus presenting an important modeling advantage, i.e. that of providing a better understanding of the CLSCs. The applicability of the formulation is tested with a real sized example of a Portuguese glass company.

Ramos, Luís, Dário Ferreira, Sandra Saraiva Ferreira, Célia Nunes, and João Tiago Mexia. "Approximate Normality of Low Degree Polynomials in Normal Independent Variables." Far East Journal of Mathematical Sciences. 68.2 (2012): 287-296.Website
Salgado, R., J. P. Noronha, A. Oehmen, G. Carvalho, and M. A. M. Reis. "Biodegradation of clofibric acid and identification of its metabolites." . Hazard. Mat. . 241-242.30 (2012): 182-189.Biodegradation of Clofibric Acid and Identification of its Metabolites.pdf
Ferraz, Ricardo, Luís C. Branco, Isabel M. Marrucho, João M. M. Araújo, Luis Paulo N. Rebelo, Manuel Nunes da Ponte, Cristina Prudêncio, João Paulo Noronha, and Zeljko Petrovski. "Development of novel ionic liquids based on ampicillin." Med. Chem. Commun.. 3 (2012): 494.Development of Novel Ionic Liquids Based on Ampicillin.pdf
Queirós, Raquel B., J. P. Noronha, P. V. S. Marques, and Goreti M. F. Sales. "Emerging (bio)sensing Technology for Assessing and Monitoring Freshwater Contamination – Methods and Applications." Ecological Water Quality - Water Treatment and Reuse. InTech, 2012. 65-94.Emerging Bio Sensing Technology for Assessing and Monitoring Freshwater Contamination Methods and Applications.pdf
Bras, Joana L. A., Ana Luisa Carvalho, Aldino Viegas, Shabir Najmudin, Victor D. Alves, Jose A. M. Prates, Luis M. A. Ferreira, Maria J. Romao, Harry J. Gilbert, and Carlos M. G. A. Fontes. "Escherichia coli expression, purification, crystallization, and structure determination of bacterial cohesin-dockerin complexes." Methods in enzymology. Vol. 510. 2012. 395-415. Abstract

Cellulosomes are highly efficient nanomachines that play a fundamental role during the anaerobic deconstruction of complex plant cell wall carbohydrates. The assembly of these complex nanomachines results from the very tight binding of repetitive cohesin modules, located in a noncatalytic molecular scaffold, and dockerin domains located at the C-terminus of the enzyme components of the cellulosome. The number of enzymes found in a cellulosome varies but may reach more than 100 catalytic subunits if cellulosomes are further organized in polycellulosomes, through a second type of cohesin-dockerin interaction. Structural studies have revealed how the cohesin-dockerin interaction mediates cellulosome assembly and cell-surface attachment, while retaining the flexibility required to potentiate catalytic synergy within the complex. Methods that might be applied for the production, purification, and structure determination of cohesin-dockerin complexes are described here. Copyright 2012 Elsevier Inc. All rights reserved.

Mendes, Ana Sofia, Maria Amalia Botelho, Ana Luisa Papoila, João Viegas, Daniel Aelenei, Paixão, P. Paquete, Iolanda Caires, Susana Azevedo, Pedro Martins, J. Martins, C. Pedro, P. Neves, Nuno Neuparth, and João Teixeira. "Geria Project preliminary study on indoor air quality and health related quality of life in elderly care centers." CISE 2012, Conference. 2012. Abstract

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Cano, Manuela, Susana Nogueira, Ana Luisa Papoila, F. Aguiar, Pedro Martins, J. Marques, Iolanda Caires, J. Martins, C. Pedro, P. Paixão, J. Rosado-Pinto, Paula Leiria-Pinto, Daniel Aelenei, Ana Mendes, João Teixeira, M. C. Proença, and Nuno Neuparth. "Indoor Air Quality in Portuguese Children Day Care Centers ? ENVIRH Project." The Second International Conference on Building Energy and Environment (COBEE). 978-0-9816881-9-0; 0-9816881-9-5. 2012. Abstract

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Zajega, F., Mancas M., Ben Mandhkour R., Leroy J., Riche N., Rocca F., Rybarczyk Y., and Dutoit T. "KinAct: the attentive social game demonstration." 11th Asian Conference on Computer Vision. Daejeon, Korea 2012. copy.pdf
Pereira, Pedro, Helena Fino, Fernando Coito, and M. Ventim-Neves. "Optimization-Based Design of Nano-CMOS LC-VCOs." Doctoral Conference on Computing, Electrical and Industrial Systems, DoCEIS 2012. Eds. Luis Camarinha-Matos, Ehsan Shahamatnia, and Gonçalo Nunes. Vol. 372. IFIP Advances in Information and Communication Technology, 372. Costa de Caparica - Portugal: Springer Boston, 2012. 453-464. Abstract

This paper introduces a variability-aware methodology for the design of LC-VCOs in Nano-CMOS technologies. The complexity of the design as well as the necessity for having an environment offering the possibility for exploring design trade-offs has led to the development of design methodologies based multi-objective optimization procedures yielding the generation of Pareto-optimal surfaces. The efficiency of the process is granted by using analytical models for both passive and active devices. Although physics-based analytical expressions have been proposed for the evaluation of the lumped elements, the variability of the process parameters is usually ignored due to the difficulty to formalize it into an optimization performance index. The usually adopted methodology of considering only optimum solutions for the Pareto surface, may lead to pruning quasi-optimal solutions that may prove to be better, should their sensitivity to process parameter variation be accounted for. In this work we propose starting by generating an extended Pareto surface where both optimum and quasi-optimum solutions are considered. Finally information on the sensitivity to process parameter variations, is used for electing the best design solution.

Zeballos, L. J., M. I. Gomes, A. P. Barbosa-Povoa, and A. Q. Novais. "Optimum Design and Planning of Resilient and Uncertain Closed-Loop Supply Chains." 22nd European Symposium on Computer Aided Process Engineering. Eds. Ian David Lockhart Bogle, and Michael Fairweather. Vol. 30. Computer Aided Chemical Engineering, 30. London: Elsevier, 2012. 407-411. Abstract

The design and planning of efficient supply chains (SC) is a major challenge that increases when the return of products has to be accounted for, the so-called closed-loop supply chains (CLSC). In the present work the effect of disruptions and modifications in the operating conditions of CLSCs are investigated on the basis of a 2-stage scenario based model previously developed by the authors. Metrics derived from graph theory are used, along with more conventional economic and operational indices. A discussion on the results obtained is presented to assess how the design and planning of the CLSC respond to these challenges and how these metrics may contribute to this objective.

Pereira, Pedro, Fernando Coito, and Helena Fino. "PSO-Based Design of RF Integrated Inductor." Doctoral Conference on Computing, Electrical and Industrial Systems, DoCEIS 2012. Eds. Luis Camarinha-Matos, Ehsan Shahamatnia, and Gonçalo Nunes. Vol. 372. IFIP Advances in Information and Communication Technology, 372. Costa de Caparica - Portugal: Springer Boston, 2012. 475-482. Abstract

This paper addresses an optimization-based approach for the design of RF integrated inductors. The methodology presented deals with the complexity of the design problem by formulating it as a multi-objective optimization. The multi-modal nature of the underlying functions combined with the need to be able to explore design trade-offs leads to the use of niching methods. This allows exploring not only the best trade-off solutions lying on the Pareto-optimum surface but also the quasi-optimum solutions that would be otherwise discarded. In this paper we take advantage of the niching properties of lbest PSO algorithm using ring topology to devise a simple optimizer able to find the local-optima. For the efficiency of the process analytical models are used for the passive/active devices. In spite the use of physics-based analytical expressions for the evaluation of the lumped elements, the variability of the process parameters is ignored in the optimization stage due to the significant computational burden it involves. Thus in the final stage both the Pareto-optimum solutions and the quasi-optimum solutions are evaluated with respect to the sensitivity to process parameter variations.

Zeballos, Luis J., Maria Isabel Gomes, Ana Paula Barbosa-póvoa, and Augusto Q. Novais. "Uncertain quality and quantity of returns in a closed-loop supply chain." Foundations of Computer-aided Process Operations. Savannah, USA 2012. Abstract

In this work the design and planning of a Closed-Loop Supply Chain (CLSC) under uncertain conditions is considered and a two-stage scenario-based modeling approach is proposed in order to deal with this multi-product, multi-period problem. The network design and tactical plan are simultaneously optimized in a given time horizon, comprehending the raw material acquisition and the processing, storage and distribution of intermediates, returns and final products. Uncertainty is associated to the returns, both in terms of their quantity, which is customer dependent, and quality, which is determined at the sorting centers. Therefore, the ensuing mathematical MILP formulation considers the simultaneous integration of two important uncertainty sources, which represents an important modeling advantage, allowing a better understanding of the reverse network structure. For each probabilistic scenario, the model estimates the amount of products to be returned by customers and of returns to be remanufactured for each quality level, as well as the storage levels. Several tests based on a real sized example of a Portuguese glass company are undertaken in order to show the applicability of the developed approach. Based on these tests, the influence of the uncertain quality and quantity of returns on the design and planning of the CLSC is assessed.

Neves, Nuno, Raquel Barros, Elsa Antunes, João Calado, Elvira Fortunato, Rodrigo Martins, and Isabel Ferreira. "Aluminum doped zinc oxide sputtering targets obtained from nanostructured powders: Processing and application." Journal of the European Ceramic Society (2012). Abstract
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b Neves, N.a b, Barros Antunes Calado Fortunato Martins Ferreira R. a E. a. "Aluminum doped zinc oxide sputtering targets obtained from nanostructured powders: Processing and application." Journal of the European Ceramic Society. 32 (2012): 4381-4391. AbstractWebsite

This work reports the production of ceramic targets based on nanostructured Al-doped ZnO (AZO) powders for sputtering applications. The nanostructured powder is obtained by a new patented process based on the detonation of an emulsion containing both Zn and Al metal precursors in the final proportion of 98:2wt% (ZnO:Al 2O 3), through which the Al contains is highly uniform distributed over ZnO. Due to the nanostructured powder characteristics, the targets can be sintered at substantially lower temperatures (1150-1250°C) by conventional sintering, contributing to production costs reduction of ceramic targets and consequently the costs of photovoltaic and displays industries. Electrical resistivity values around 3.0-7.0×10 -3Ωcm have been obtained depending on final microstructure of the targets. The electro-optical properties of the films produced at room temperature with thicknesses around 360nm, besides being highly uniform exhibit a resistivity of about 1×10 -3Ωcm and a transmittance in the visible range above 90%. © 2012 Elsevier Ltd.

Soares, Paula I. P., Isabel M. M. Ferreira, Rui A. G. B. N. Igreja, Carlos M. M. Novo, and Joao P. M. R. Borges. "Application of Hyperthermia for Cancer Treatment: Recent Patents Review." Recent Patents on Anti-Cancer Drug Discovery. 7 (2012): 64-73. Abstract

Cancer is one of the main causes of death in the world and its incidence increases every day. Current treatments are insufficient and present many breaches. Hyperthermia is an old concept and since early it was established as a cancer treatment option, mainly in superficial cancers. More recently the concept of intracellular hyperthermia emerged wherein magnetic particles are concentrated at the tumor site and remotely heated using an applied magnetic field to achieve hyperthermic temperatures (42-45 degrees C). Many patents have been registered in this area since the year 2000. This review presents the most relevant information, organizing them according to the hyperthermic method used: 1) external RadioFrequency devices; 2) hyperthermic perfusion; 3) frequency enhancers; 4) apply heating to the target site using a catheter; 5) injection of magnetic and ferroelectric particles; 6) injection of magnetic nanoparticles that may carry a pharmacological active drug. The use of magnetic nanoparticles is a very promising treatment approach since it may be used for diagnostic and treatment. An ideal magnetic nanoparticle would be able to detect and diagnose the tumor, carry a pharmacological active drug to be delivered in the tumor site, apply hyperthermia through an external magnetic field and allow treatment monitoring by magnetic resonance imaging.

Cardoso, Alberto, M. T. Restivo, P. Cioga, M. Delgado, J. N. Monsanto, J. Bicker, E. Nunes, and P. Gil. "Demonstration of Online Educational Modules with Online Experiments." REV2012 - Remote Engineering & Virtual Instrumentation. n/a 2012. Abstract
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Soares, P. I. P., S. J. R. Dias, C. M. M. Novo, I. M. M. Ferreira, and J. P. Borges. "Doxorubicin vs. ladirubicin: methods for improving osteosarcoma treatment." Mini Reviews in Medicinal Chemistry. 12.12 (2012): 1239-1249. Abstract
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Vinagre, C., D. Madeira, L. Narciso, H. N. Cabral, and M. S. Diniz. "Effect of handling, confinement and crowding in HSP70 production in Pachygrapsus marmoratus, a model species for climate change experiments." Journal of Sea Research. 72 (2012): 64-68. AbstractWebsite
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