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2012
Baltazar, LG, Henriques FMA, Jorne F.  2012.  Grout optimisation for old masonry consolidation, 18th-20th Decemb. Proceedings of the 4th National Congress on Construction. , Coimbra, Portugal
Baltazar, LG, Henriques FMA, Jorne F.  2012.  Hydraulic lime grouts for masonry injection – effects of admixtures on the fresh grout properties, 15th - 17th Octo. Proceedings of the 8th International Conference on Structural Analysis of Historical Constructions. , Wroclaw, Poland
Brás, A, Henriques FMA, Cidade MT.  2012.  - Rheological behaviour of hydraulic lime-based grouts. Shear-time and temperature dependence. Mechanics of Time-Dependent Materials. DOI 10.1007/s11043-012-9202-0
Brecher, C, Breitbach T, Müller S, Mayer MP, Odenthal B, Schlick C, Herfs W.  2012.  3D Assembly Group Analysis for Cognitive Automation. Journal of Robotics. 2012(1):1-18. AbstractWebsite

A concept that allows the cognitive automation of robotic assembly processes is introduced. An assembly cell comprised of two robots was designed to verify the concept. For the purpose of validation a customer-defined part group consisting of Hubelino bricks is assembled. One of the key aspects for this process is the verification of the assembly group. Hence a software component was designed that utilizes the Microsoft Kinect to perceive both depth and color data in the assembly area. This information is used to determine the current state of the assembly group and is compared to a CAD model for validation purposes. In order to efficiently resolve erroneous situations, the results are interactively accessible to a human expert. The implications for an industrial application are demonstrated by transferring the developed concepts to an assembly scenario for switch-cabinet systems.

Kuz, S, Heinicke A, Schwichtenhövel D, Mayer MP, Schlick C.  2012.  The Effect of Anthropomorphic Movements of Assembly Robots on Human Prediction. Advances in Ergonomics in Manufacturing. (Karwowski, W., Trzcielinski, S., Eds.).:263-271., Boca Raton, FL: CRC Press Abstract

From a user centered point of view an important basic requirement to enable human-robot cooperation is to achieve conformity with operator's expectations of robot behavior. Therefore, this study focuses on the question, whether anthropomorphic robot movement trajectories can lead to an improved anticipation of the robot's behavior. Based on a virtual simulation environment a robotized assembly cell consisting of the assembly robot and the actual workplace was considered. In order to be able to simulate anthropomorphic movements, the human wrist trajectories of defined pick and place movements were obtained using an infrared motion capture system. The captured data were used to navigate the virtual assembly robot. Within the experiment anthropomorphic and robotic trajectories were distinguished. During the experiment, the main task of the participants was to predict the movement's destination as quickly as possible. Thus, the corresponding reaction value was analyzed to investigate the influence of anthropomorphic robot movements on human prediction in industrial environments.

Miller, A. Z., Hernández-Mariné, M., Jurado, V., Dionísio, A., Barquinha, Fortunato, Afonso, M. J., Chaminé, H. I., Saiz-Jimenez C.  2012.  Enigmatic reticulated filaments in subsurface granite. Environmental Microbiology Reports. 4(6):596–603.
Muller, C, Marcou G, Horvath D, Aires-de-Sousa J, Varnek A.  2012.  Models for Identification of Erroneous Atom-to-Atom Mapping of Reactions Performed by Automated Algorithms. J. Chem. Inf. Model. 52(12):3116-3122.Website
Brás, A, Henriques FMA.  2012.  Natural hydraulic lime based grouts- the selection of grout injection parameters for masonry consolidation. Construction & Building Materials. 26:135-144.
Fournier, G, Hinderer H, Schmid D, Seign R, Baumann M.  2012.  The new mobility paradigm: Transformation of value chain and business models. Enterprise and Work Innovation Studies. 8:9-40. AbstractWebsite

Four categories of innovations have been identified by Freeman and Perez: incremental innovations, radical innovations, new technological systems (systemic innovations), and technological revolutions or new techno-economic paradigms. New techno-economic paradigms represent changes in technological systems that are so far-reaching in their effects that they have a major influence on the behaviour of the entire economy. Scarcity of oil and external costs like global warming are the key arguments and the main drivers of the change of the current paradigm. They will affect especially the mobility of individuals and the interlinked business models. Novel business models within newly created markets will raise e.g. extended mobility services, activities aiming at the infrastructure, new opportunities in the field of energy transmission and supply and even new strategies of recycling, reusing or reducing the use of resources in order to address global scarcity issues. Especially for the established players of the automotive industry like original equipment manufacturers (OEMs) or 1st and 2nd tier suppliers this implicates opportunities and risks at the same time. But also new players will get the chance to create and enter new markets with new or extended products or services and lead the new value chain. This paper compiles and evaluates current approaches and business models of selected OEMs together with upcoming players. Additionally their positions within the existing value chain are being analyzed and classified. Bringing together the identified drivers of changes with current trends within the automotive industry the authors also show new concepts of extended business models, e.g. the idea of an ecosystem, that have the potential to cause an additional shift of power within the global mobility value chain.

Baltazar, LG, Henriques FMA, Jorne F.  2012.  Optimisation of flow behaviour and stability of superplasticized fresh hydraulic lime grouts through design of experiments. Construction & Building Materials . 35:838-845.
Maia, MJ, Moiteiro AI, Horstink L, Farelo M, Antunes R.  2012.  {Análise de um processo decisório controverso: a co-incineração em Souselas [Analysis of a controversial decision process: the co-incineration at Souselas]}. , Number 10/2012: Universidade Nova de Lisboa, IET/CICS.NOVA-Interdisciplinary Centre on Social Sciences, Faculty of Science and Technology Abstract

The scientific controversy generated around the destiny given to the fraction of hazardous industrial waste produced in Portugal and how the country dealt with this situation was the stand out point in Souselas case. Here, the dominant aspect of the analysis focused on the implementation of a solution for the treatment of hazardous industrial waste. These wastes result from industrial processes contain or are contaminated, by substances that, at certain concentrations, represent a risk to human health or to the environment. Their treatment can be done using co-incineration in existing cement factories. Having in mind the environment analysis of a controversial process, through the statements made by the different actors involved, the case of Souselas was our object of study. Initially, the actors involved in the process were identified and characterized, in terms of position, interests and / or concerns. This analysis has strengthened with the gathering of documentary elements of analysis. In a second phase the historical process was prepared. Only then, the conditions to make an interpretation of what really happened in the process were gathered, then , it was possible to identify which parts were successful and unsuccessful, and to interpret “why” these successes and failures occurred. Thus, after the identification of key variables and leverage points, a causal diagram and a schematic simulation of the behaviour of reference in case Souselas was designed. We conclude that the process of Souselas was a significant milestone with regard to social organization and spontaneous local actors in situations of opposition to central government decisions with local impact. It was also a turning point in governance according to the model of representative democracy, whose technocratic and elitist character is called into question. The Souselas case emphasized itself as a microcosm on the conflict of interests that we find at a global level heightened since the 90s and that

Costa, C, Pinheiro C, Henriques I, Laia CAT.  2012.  Electrochromic Properties of Inkjet Printed Vanadium Oxide Gel on Flexible Polyethylene Terephthalate/Indium Tin Oxide Electrodes. Acs Applied Materials & Interfaces. 4:5266-5275., Number 10 AbstractWebsite
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Costa, C, Pinheiro C, Henriques I, Laia CAT.  2012.  Inkjet Printing of Sol-Gel Synthesized Hydrated Tungsten Oxide Nanoparticles for Flexible Electrochromic Devices. Acs Applied Materials & Interfaces. 4:1330-1340., Number 3 AbstractWebsite
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Pimenta, J, Dias FMV, Marques CC, Baptista MC, Vasques MI, Horta AEM, Barbas JP, Soares R, Mesquita P, Cabrita E, Fontes C, Prates JA, Pereira RM.  2012.  The Prion-like Protein Doppel Enhances Ovine Spermatozoa Fertilizing Ability. Reproduction in Domestic Animals. 47:196-202. Abstract

The function of prion-like protein Doppel was suggested to be related to male fertility. In this study, the importance of ovine Doppel polypeptide on spermatozoa capacitation and fertilization was evaluated. After refolding, recombinant Doppel (rDpl) was supplemented with different concentrations (40, 80 or 190 ng/ml) to ovine spermatozoa during the capacitation process. In experiment 1, post-thawed ovine spermatozoa were incubated with different concentrations of rDpl during 1 h for swim-up, and changes in sperm motility, concentration, vigour, viability and capacitation were monitored (10 replicates). In experiment 2, the fertilization ability of post-swim-up spermatozoa incubated as above was tested through heterologous fertilization of bovine in vitro matured oocytes (n = 423, three replicates). Regardless of dosage, rDpl improved (p = 0.03) spermatozoa viability. Sperm individual motility and vigour were the highest (p = 0.04) for the group receiving 190 ng/ml rDpl. Sperm supplemented with the highest doses of rDpl achieved higher (p = 0.02) fertilization rates (56.0 +/- 3.0%) than control (39.1 +/- 2.2%) and 40 ng/ml rDpl (39.8 +/- 2.7%). Preliminary data suggest that Doppel protein may enhance in vitro spermatozoa fertilizing ability.

Pereira, AS, Timoteo CG, Guilherme M, Folgosa F, Naik SG, Duarte AG, Huynh BH, Tavares P.  2012.  Spectroscopic Evidence for and Characterization of a Trinuclear Ferroxidase Center in Bacterial Ferritin from Desulfovibrio vulgaris Hildenborough. Journal Of The American Chemical Society. {134}:{10822-10832}., Number {26} Abstract

Ferritins are ubiquitous and can be found in practically all organisms that utilize Fe. They are composed of 24 subunits forming a hollow sphere with an inner cavity of similar to 80 angstrom in diameter. The main function of ferritin is to oxidize the cytotoxic Fe2+ ions and store the oxidized Fe in the inner cavity. It has been established that the initial step of rapid oxidation of Fe2+ (ferroxidation) by H-type ferritins, found in vertebrates, occurs at a diiron binding center, termed the ferroxidase center. In bacterial ferritins, however, X-ray crystallographic evidence and amino acid sequence analysis revealed a trinuclear Fe binding center comprising a binuclear Fe binding center (sites A and B), homologous to the ferroxidase center of H-type ferritin, and an adjacent mononuclear Fe binding site (site C). In an effort to obtain further evidence supporting the presence of a trinuclear Fe binding center in bacterial ferritins and to gain information on the states of the iron bound to the trinuclear center, bacterial ferritin from Desulfovibrio vulgaris (DvFtn) and its E130A variant was loaded with substoichiometric amounts of Fe2+, and the products were characterized by Mossbauer and EPR spectroscopy. Four distinct Fe species were identified: a paramagnetic diferrous species, a diamagnetic diferrous species, a mixed valence Fe2+Fe3+ species, and a mononuclear Fe2+ species. The latter three species were detected in the wild-type DvFtn, while the paramagnetic diferrous species was detected in the E130A variant. These observations can be rationally explained by the presence of a trinuclear Fe binding center, and the four Fe species can be properly assigned to the three Fe binding sites. Further, our spectroscopic data suggest that (1) the fully occupied trinuclear center supports an all ferrous state, (2) sites B and C are bridged by a mu-OH group forming a diiron subcenter within the trinuclear center, and (3) this subcenter can afford both a mixed valence Fe2+Fe3+ state and a diferrous state. Mechanistic insights provided by these new findings are discussed and a minimal mechanistic scheme involving O-O bond cleavage is proposed.

2011
Timoteo, CG, Pereira AS, Martins CE, Naik SG, Duarte AG, Moura JJ, Tavares P, Huynh BH, Moura I.  2011.  Low-spin heme b(3) in the catalytic center of nitric oxide reductase from Pseudomonas nautica, May 24. Biochemistry. 50:4251-62., Number 20 AbstractWebsite

Respiratory nitric oxide reductase (NOR) was purified from membrane extract of Pseudomonas (Ps.) nautica cells to homogeneity as judged by polyacrylamide gel electrophoresis. The purified protein is a heterodimer with subunits of molecular masses of 54 and 18 kDa. The gene encoding both subunits was cloned and sequenced. The amino acid sequence shows strong homology with enzymes of the cNOR class. Iron/heme determinations show that one heme c is present in the small subunit (NORC) and that approximately two heme b and one non-heme iron are associated with the large subunit (NORB), in agreement with the available data for enzymes of the cNOR class. Mossbauer characterization of the as-purified, ascorbate-reduced, and dithionite-reduced enzyme confirms the presence of three heme groups (the catalytic heme b(3) and the electron transfer heme b and heme c) and one redox-active non-heme Fe (Fe(B)). Consistent with results obtained for other cNORs, heme c and heme b in Ps. nautica cNOR were found to be low-spin while Fe(B) was found to be high-spin. Unexpectedly, as opposed to the presumed high-spin state for heme b(3), the Mossbauer data demonstrate unambiguously that heme b(3) is, in fact, low-spin in both ferric and ferrous states, suggesting that heme b(3) is six-coordinated regardless of its oxidation state. EPR spectroscopic measurements of the as-purified enzyme show resonances at the g approximately 6 and g approximately 2-3 regions very similar to those reported previously for other cNORs. The signals at g = 3.60, 2.99, 2.26, and 1.43 are attributed to the two charge-transfer low-spin ferric heme c and heme b. Previously, resonances at the g approximately 6 region were assigned to a small quantity of uncoupled high-spin Fe(III) heme b(3). This assignment is now questionable because heme b(3) is low-spin. On the basis of our spectroscopic data, we argue that the g = 6.34 signal is likely arising from a spin-spin coupled binuclear center comprising the low-spin Fe(III) heme b(3) and the high-spin Fe(B)(III). Activity assays performed under various reducing conditions indicate that heme b(3) has to be reduced for the enzyme to be active. But, from an energetic point of view, the formation of a ferrous heme-NO as an initial reaction intermediate for NO reduction is disfavored because heme [FeNO](7) is a stable product. We suspect that the presence of a sixth ligand in the Fe(II)-heme b(3) may weaken its affinity for NO and thus promotes, in the first catalytic step, binding of NO at the Fe(B)(II) site. The function of heme b(3) would then be to orient the Fe(B)-bound NO molecules for the formation of the N-N bond and to provide reducing equivalents for NO reduction.

Mathies, G, Blok H, Disselhorst JA, Gast P, van der Meer H, Miedema DM, Almeida RM, Moura JJ, Hagen WR, Groenen EJ.  2011.  Continuous-wave EPR at 275GHz: application to high-spin Fe(3+) systems, May. J Magn Reson. 210:126-32., Number 1 AbstractWebsite

The 275GHz electron-paramagnetic-resonance spectrometer we reported on in 2004 has been equipped with a new probe head, which contains a cavity especially designed for operation in continuous-wave mode. The sensitivity and signal stability that is achieved with this new probe head is illustrated with 275GHz continuous-wave spectra of a 1mM frozen solution of the complex Fe(III)-ethylenediamine tetra-acetic acid and of 10mM frozen solutions of the protein rubredoxin, which contains Fe(3+) in its active site, from three different organisms. The high quality of the spectra of the rubredoxins allows the determination of the zero-field-splitting parameters with an accuracy of 0.5GHz. The success of our approach results partially from the enhanced absolute sensitivity, which can be reached using a single-mode cavity. At least as important is the signal stability that we were able to achieve with the new probe head.

Hédoux, A, Guinet Y, Derollez P, Dudognon E, Correia NT.  2011.  Raman spectroscopy of racemic ibuprofen: Evidence of molecular disorder in phase II. International Journal of Pharmaceutics. 421:42-52.
Goncalves A., Costa C., Pereira S., Correia N., M.M. S, Barbosa P.C., L.C. R, Henriques I., R. M, Fortunato E..  2011.  Study of electrochromic devices with nanocomposites polymethacrylate hydroxyethylene resin based electrolyte. Polym. Adv. Technol.. 23:791–795.
Henriques, MX, Rodrigues T, Carido M, Ferreira L, Filipe SR.  2011.  Synthesis of capsular polysaccharide at the division septum of Streptococcus pneumoniae is dependent on a bacterial tyrosine kinase. Mol. Microbiol. 82:515-534.
Dias, AMGC, Hussain A, Marcos AS, Roque ACA.  2011.  A biotechnological perspective on the application of iron oxide magnetic colloids modified with polysaccharides. Biotechnology Advances. 29:142–155., Number 1 AbstractWebsite

Iron oxide magnetic nanoparticles {(MNPs)} alone are suitable for a broad spectrum of applications, but the low stability and heterogeneous size distribution in aqueous medium represent major setbacks. These setbacks can however be reduced or diminished through the coating of {MNPs} with various polymers, especially biopolymers such as polysaccharides. Polysaccharides are biocompatible, non-toxic and renewable; in addition, they possess chemical groups that permit further functionalization of the {MNPs.} Multifunctional entities can be created through decoration with specific molecules e.g. proteins, peptides, drugs, antibodies, biomimetic ligands, transfection agents, cells, and other ligands. This development opens a whole range of applications for iron oxide nanoparticles. In this review the properties of magnetic structures composed of {MNPs} and several polysaccharides {(Agarose}, Alginate, Carrageenan, Chitosan, Dextran, Heparin, Gum Arabic, Pullulan and Starch) will be discussed, in view of their recent and future biomedical and biotechnological applications.

Mahro, M, Coelho C, Trincao J, Rodrigues D, Terao M, Garattini E, Saggu M, Lendzian F, Hildebrandt P, Romao MJ, Leimkuehler S.  2011.  Characterization and Crystallization of Mouse Aldehyde Oxidase 3: From Mouse Liver to Escherichia coli Heterologous Protein Expression. Drug Metabolism and Disposition. 39:1939-1945., Number 10 AbstractWebsite
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Timoteo, CG, Pereira AS, Martins CE, Naik SG, Duarte AG, Moura JJG, Tavares P, Huynh BH, Moura I.  2011.  Low-Spin Heme b(3) in the Catalytic Center of Nitric Oxide Reductase from Pseudomonas nautica. Biochemistry. {50}:{4251-4262}., Number {20} Abstract

Respiratory nitric oxide reductase (NOR) was purified from membrane extract of Pseudomonas (Ps.) nautica cells to homogeneity as judged by polyacrylamide gel electrophoresis. The purified protein is a heterodimer with subunits of molecular masses of 54 and 18 kDa. The gene encoding both subunits was cloned and sequenced. The amino acid sequence shows strong homology with enzymes of the cNOR class. Iron/heme determinations show that one heme c is present in the small subunit (NORC) and that approximately two heme b and one non-heme iron are associated with the large subunit (NORB), in agreement with the available data for enzymes of the cNOR class. Mossbauer characterization of the as-purified, ascorbate-reduced, and dithionite-reduced enzyme confirms the presence of three heme groups (the catalytic heme b(3) and the electron transfer heme b and heme c) and one redox-active non-heme Fe (Fe-B). Consistent with results obtained for other cNORs, heme c and heme b in Ps. nautica cNOR were found to be low-spin while FeB was found to be high-spin. Unexpectedly, as opposed to the presumed high-spin state for heme b(3), the Mossbauer data demonstrate unambiguously that heme b(3) is, in fact, low-spin in both ferric and ferrous states, suggesting that heme b(3) is six-coordinated regardless of its oxidation state. EPR spectroscopic measurements of the as-purified enzyme show resonances at the g similar to 6 and g similar to 2-3 regions very similar to those reported previously for other cNORs. The signals at g = 3.60, 2.99, 2.26, and 1.43 are attributed to the two charge-transfer low-spin ferric heme c and heme b. Previously, resonances at the g similar to 6 region were assigned to a small quantity of uncoupled high-spin Fe-III heme b(3). This assignment is now questionable because heme b(3) is low-spin. On the basis of our spectroscopic data, we argue that the g = 6.34 signal is likely arising from a spin spin coupled binuclear center comprising the low-spin Fe-III heme b(3) and the high-spin Fe-B(III). Activity assays performed under various reducing conditions indicate that heme b(3) has to be reduced for the enzyme to be active. But, from an energetic point of view, the formation of a ferrous heme-NO as an initial reaction intermediate for NO reduction is disfavored because heme [FeNO](7) is a stable product. We suspect that the presence of a sixth ligand in the Fe-II-heme b(3) may weaken its affinity for NO and thus promotes, in the first catalytic step, binding of NO at the Fe-B(II) site. The function of heme b(3) would then be to orient the Fe-B-bound NO molecules for the formation of the N-N bond and to provide reducing equivalents for NO reduction.

Pereira, P, Helena Fino M, Coito F, Ventim-Neves M.  2011.  RF integrated inductor modeling and its application to optimization-based design. Analog Integrated Circuits and Signal Processing. :1–9.: Springer Abstract

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