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2014
Marinheiro, J., O. Mateus, A. Alaoui, F. Amani, M. Nami, and C. Ribeiro. "New Quaternary fossil sites from the Middle Atlas of Morocco." Comunicações Geológicas. 101, Especial I (2014): 485-488. Abstractmarinheiro_et_al_2014_new_quaternary_fossil_sites_from_the_middle_atlas_of_morocco.pdf

The paleontological richness of Morocco has been scientifically known since at least the early 20th century. The region of the Middle Atlas, more specifically the Boulemane area, has been however only sparsely studied since the 1960s when it provided vertebrate fossils from the Middle Jurassic. In September 2013, a Moroccan-Portuguese expedition to the village of Taghrout, Boulemane, made excavations in a Pleistocene fossil site that once was a small high-altitude sedimentary basin, uncharted in previous geological maps. The excavations yielded bone material from large mammals, the most common findings are elephants ascribed to Elephas, but artiodactyls, turtles, and in-situ Acheulean tools were also collected. This represents a new and important paleontological and archeological site. In addition to the discoveries of Taghrout, the expedition also retrieved Quaternary vertebrate material from a nearby cave and found new Jurassic localities, with arcosaur bones and dinosaur footprints, in El Mers.

Maiti, Biplab K., Luisa B. Maia, Kuntal Pal, Bholanath Pakhira, Teresa Aviles, Isabel Moura, Sofia R. Pauleta, Jose L. Nunez, Alberto C. Rizzi, Carlos D. Brondino, Sabyasachi Sarkar, and Jose J. G. Moura. "One electron reduced square planar bis(benzene-1,2-dithiolato) copper dianionic complex and redox switch by O2/HO-." Inorganic Chemistry. 53 (2014): 12799-12808. AbstractWebsite
Simões, J. T., L. C. Neves, Nunes A. Antão, and Costa N. M. da Guerra. "Pro- babilisti analysis of bearing apa ity of shallow foundations using three-dimensional limit analyses." International Journal of Computational Methods. 11.2 (2014).
Boavida, Nuno, António Moniz, and Manuel Laranja. "Towards an assessment of the Portuguese e-mobility case; The Mobi-E." Technology assessment and policy areas of great transitions. Eds. T. Michalek, L. Hebakova, L. Hennen, C. Scherz, L. Nierling, and J. Hahn. Prague: Technology Centre ASCR, 2014. 263-269.
Gao, Chao, Yan Liu, Hongtao Zhang, Yibing Zhang, Michiko N. Fukuda, Angelina S. Palma, Radoslaw P. Kozak, Robert A. Childs, Motohiro Nonaka, Zhen Li, Don L. Siegel, Peter Hanfland, Donna M. Peehl, Wengang Chai, Mark I. Greene, and Ten Feizi. "Carbohydrate Sequence of the Prostate Cancer-associated Antigen F77 Assigned by a Mucin O-Glycome Designer Array." Journal of Biological Chemistry. 289 (2014): 16462-16477. Abstract
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Soares, Paula I. P., Ana MR Alves, Laura CJ Pereira, Joana T. Coutinho, Isabel M. M. Ferreira, Carlos M. M. Novo, and João PMR Borges. "Effects of surfactants on the magnetic properties of iron oxide colloids." Journal of Colloid and Interface Science. 419 (2014): 46-51. Abstract
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Mendes, Ana, Daniel Aelenei, Ana Luisa Papoila, Pedro Carreiro-Martins, Livia Aguiar, Cristiana Pereira, Paula Neves, Susana Azevedo, Manuela Cano, Carmo Proenca, and others. "Environmental and Ventilation Assessment in Child Day Care Centers in Porto: The Envirh Project." Journal of Toxicology and Environmental Health, Part A. 77 (2014): 931-943. Abstract

Children attending day care centers (CDCC) have been reported to be more prone to infectious diseases when compared with those cared for at home, and are exposed to conditions that may increase the risk of allergies and asthma. Several studies revealed that consequences of poor ventilation conditions include high levels of carbon dioxide (CO2) and many other indoor pollutants commonly detected in schools. Nine child day care centers were selected randomly to participate in this study. Fifty-two classrooms were assessed for chemical, biological, physical, and allergen parameters in spring and winter seasons in these nine CDCC located in Porto, Portugal. Outdoor measurements were also conducted for comparison. Our results indicated that (i) particulate matter (PM10) median levels were above the national reference levels, both by classroom type and by season; (ii) TVOC kindergarten peak values may raise some concern; (iii) CO2 was present at high median and maximum levels during spring and winter assessment in both nurseries and kindergartens classrooms; (iv) total bacteria concentrations were 57- and 52-fold higher in the nursery and kindergarten than outdoors, respectively, for the spring season; (v) winter and spring median predicted mean vote (PMV) indices were between "neutral" (0) and "slightly cool" (? -1) in the thermal sensation scale for comfort situations (-2 to 2) for both types of classrooms; (vi) there were significant differences for both PMV and predicted percentage of dissatisfied (PPD) indices by season; and (vii) CO2, total bacteria, and gram-negative bacteria were associated with low airflow rates. These data will help to evaluate the effectiveness of current building operation practices in child day care centers regarding indoor air quality and respiratory health.

Nico, C. a, R. a Fernandes, M. P. F. a Graça, M. b Elisa, B. A. b Sava, R. C. C. c Monteiro, L. a Rino, and T. a Monteiro. "Eu3+ luminescence in aluminophosphate glasses." Journal of Luminescence. 145 (2014): 582-587. AbstractWebsite

With a 4f6 electronic configuration, europium ions in the trivalent charge state are known to be efficient activators in wide band gap matrices. Embedded in the aluminophosphate (Li2O-BaO-Al 2O3-La2O3-P2O 5) glasses the optically activated Eu3+ ions lead to intense room temperature orange/red luminescence with 16-23 Cd/m2 by using ultraviolet pumping. The as-prepared and heat treated europium doped glasses for temperatures below and above Tg were studied by room temperature Raman spectroscopy, absorption, photoluminescence excitation, temperature dependent and time dependent photoluminescence. When the samples are excited by 325 nm wavelength photons, an enhancement of the red luminescence intensity by ca. one order of magnitude was found to occur for temperatures between 14 K and 350 K, for all the doped glasses. On the other hand, by using resonant excitation on the 5L6 Eu3+ excited state (λexc 390 nm) the ion emission intensity was found to be nearly constant for temperatures up to 500 K. For higher temperatures a steeper decrease of the luminescence intensity occurs due to non-radiative competitive channels described by activation energies of ca. 235 meV and 450 meV by using 325 and 390 nm wavelength photons as excitation, respectively. The lifetime of the 5D0 level in these glasses is ca. 2.93 ms. A discussion of the thermal population and de-excitation mechanisms is performed. © 2013 Elsevier B.V.

Araújo, Andreia, Carlos Caro, Manuel J. Mendes, Daniela Nunes, Elvira Fortunato, Ricardo Franco, Hugo Águas, and Rodrigo Martins. "Highly efficient nanoplasmonic SERS on cardboard packaging substrates." Nanotechnology. 25 (2014): 415202. Abstract
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Marinheiro, J., O. Mateus, A. Alaoui, F. Amani, M. Nami, and C. Ribeiro. "New Quaternary fossil sites from the Middle Atlas of Morocco." Comunica\\c cões Geológicas. 101, Especial I (2014): 485-488. Abstract

The paleontological richness of Morocco has been scientifically known since at least the early 20th century. The region of the Middle Atlas, more specifically the Boulemane area, has been however only sparsely studied since the 1960s when it provided vertebrate fossils from the Middle Jurassic. In September 2013, a Moroccan-Portuguese expedition to the village of Taghrout, Boulemane, made excavations in a Pleistocene fossil site that once was a small high-altitude sedimentary basin, uncharted in previous geological maps. The excavations yielded bone material from large mammals, the most common findings are elephants ascribed to Elephas, but artiodactyls, turtles, and in-situ Acheulean tools were also collected. This represents a new and important paleontological and archeological site. In addition to the discoveries of Taghrout, the expedition also retrieved Quaternary vertebrate material from a nearby cave and found new Jurassic localities, with arcosaur bones and dinosaur footprints, in El Mers.

Marinheiro, J., O. Mateus, A. Alaoui, F. Amani, M. Nami, and C. Ribeiro. "New Quaternary fossil sites from the Middle Atlas of Morocco." Comunicações Geológicas. 101 (2014): 485-488. Abstract
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Marinheiro, J., O. Mateus, A. Alaoui, F. Amani, M. Nami, and C. Ribeiro. "New quaternary fossil sites from the middle atlas of morocco,Novas jazidas fossilíferas do Quaternário do Médio-Atlas de Marrocos." Comunicacoes Geologicas. 101 (2014): 485-488. Abstract
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Núñez, C., M. Diniz, A. A. Dos Santos, J. L. Capelo, and C. Lodeiro. "New rhodamine dimer probes for mercury detection via color changes and enhancement of the fluorescence emission: Fast recognition in cellulose supported devices." Dyes and Pigments. 101 (2014): 156-163. AbstractWebsite
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Madeira, D., L. Narciso, H. N. Cabral, M. S. Diniz, and C. Vinagre. "Role of thermal niche in the cellular response to thermal stress: Lipid peroxidation and HSP70 expression in coastal crabs." Ecological Indicators. 36 (2014): 601-606. AbstractWebsite
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Otrelo-Cardoso, Ana Rita, Rashmi R. Nair, Marcia A. S. Correia, Maria G. Rivas, and Teresa Santos-Silva. "TupA: A Tungstate Binding Protein in the Periplasm of Desulfovibrio alaskensis G20." International Journal of Molecular Sciences. 15 (2014): 11783-11798. Abstract
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Araújo, A., C. Caro, MJ Mendes, D. Nunes, E. Fortunato, R. Franco, H. Águas, and R. Martins. "{Highly efficient nanoplasmonic SERS on cardboard packaging substrates}." Nanotechnology. 25 (2014). Abstract

© 2014 IOP Publishing Ltd. This work reports on highly efficient surface enhanced Raman spectroscopy (SERS) constructed on low-cost, fully recyclable and highly reproducible cardboard plates, which are commonly used as disposable packaging material. The active optical component is based on plasmonic silver nanoparticle structures separated from the metal surface of the cardboard by a nanoscale dielectric gap. The SERS response of the silver (Ag) nanoparticles of various shapes and sizes were systematically investigated, and a Raman enhancement factor higher than 106for rhodamine 6G detection was achieved. The spectral matching of the plasmonic resonance for maximum Raman enhancement with the optimal local electric field enhancement produced by 60 nm-sized Ag NPs predicted by the electromagnetic simulations reinforces the outstanding results achieved. Furthermore, the nanoplasmonic SERS substrate exhibited high reproducibility and stability. The SERS signals showed that the intensity variation was less than 5{%}, and the SERS performance could be maintained for up to at least 6 months.

Silva, Joana M., Ana Rita C. Duarte, Catarina A. Custódio, Praveen Sher, Ana I. Neto, António C. M. Pinho, Jaime Fonseca, Rui L. Reis, and João F. Mano. "{Nanostructured Hollow Tubes Based on Chitosan and Alginate Multilayers}." Advanced Healthcare Materials. 3 (2014): 433-440. Abstract

The design and production of structures with nanometer-sized polymer films based on layer-by-layer (LbL) are of particular interest for tissue engineering since they allow the precise control of physical and biochemical cues of implantable devices. In this work, a method is developed for the preparation of nanostructured hollow multilayers tubes combining LbL and template leaching. The aim is to produce hollow tubes based on polyelectrolyte multilayer films with tuned physical-chemical properties and study their effects on cell behavior. The final tubular structures are characterized by differential scanning calorimetry (DSC), Fourier transform infrared spectroscopy (FTIR), microscopy, swelling, and mechanical tests, including dynamic mechanical analysis (DMA) in physiological simulated conditions. It is found that more robust films could be produced upon chemical cross-linking with genipin. In particular, the mechanical properties confirms the viscoelastic properties and a storage and young modulus about two times higher. The water uptake decreases from about 390{%} to 110{%} after the cross-linking. The biological performance is assessed in terms of cell adhesion, viability, and proliferation. The results obtained with the cross-linked tubes demonstrate that these are more suitable structures for cell adhesion and spreading. The results suggest the potential of these structures to boost the development of innovative tubular structures for tissue engineering approaches.

2013
Nunes de Carvalho, C., P. Parreira, G. Lavareda, P. Brogueira, and A. Amaral. "P-type CuxS thin films: Integration in a thin film transistor structure." THIN SOLID FILMS. 543 (2013): 3-6. Abstract

CuxS thin films, 80 nm thick, are deposited by vacuum thermal evaporation of sulfur-rich powder mixture, Cu2S:S (50:50 wt.%) with no intentional heating of the substrate. The process of deposition occurs at very low deposition rates (0.1-0.3 nm/s) to avoid the formation of Cu or S-rich films. The evolution of CuxS films surface properties (morphology/roughness) under post deposition mild annealing in air at 270 degrees C and their integration in a thin film transistor (TFT) are the main objectives of this study. Accordingly, Scanning Electron Microscopy studies show CuxS films with different surface morphologies, depending on the post deposition annealing conditions. For the shortest annealing time, the CuxS films look to be constructed of grains with large dimension at the surface (approximately 100 nm) and consequently, irregular shape. For the longest annealing time, films with a fine-grained surface are found, with some randomly distributed large particles bound to this fine-grained surface. Atomic Force Microscopy results indicate an increase of the root-mean-square roughness of CuxS surface with annealing time, from 13.6 up to 37.4 nm, for 255 and 345 s, respectively. The preliminary integration of CuxS films in a TFT bottom-gate type structure allowed the study of the feasibility and compatibility of this material with the remaining stages of a TFT fabrication as well as the determination of the p-type characteristic of the CuxS material. (c) 2013 Elsevier B.V. All rights reserved.

Nunes de Carvalho, C., P. Parreira, G. Lavareda, P. Brogueira, and A. Amaral. "P-type CuxS thin films: Integration in a thin film transistor structure." THIN SOLID FILMS. 543 (2013): 3-6. Abstract

CuxS thin films, 80 nm thick, are deposited by vacuum thermal evaporation of sulfur-rich powder mixture, Cu2S:S (50:50 wt.%) with no intentional heating of the substrate. The process of deposition occurs at very low deposition rates (0.1-0.3 nm/s) to avoid the formation of Cu or S-rich films. The evolution of CuxS films surface properties (morphology/roughness) under post deposition mild annealing in air at 270 degrees C and their integration in a thin film transistor (TFT) are the main objectives of this study. Accordingly, Scanning Electron Microscopy studies show CuxS films with different surface morphologies, depending on the post deposition annealing conditions. For the shortest annealing time, the CuxS films look to be constructed of grains with large dimension at the surface (approximately 100 nm) and consequently, irregular shape. For the longest annealing time, films with a fine-grained surface are found, with some randomly distributed large particles bound to this fine-grained surface. Atomic Force Microscopy results indicate an increase of the root-mean-square roughness of CuxS surface with annealing time, from 13.6 up to 37.4 nm, for 255 and 345 s, respectively. The preliminary integration of CuxS films in a TFT bottom-gate type structure allowed the study of the feasibility and compatibility of this material with the remaining stages of a TFT fabrication as well as the determination of the p-type characteristic of the CuxS material. (c) 2013 Elsevier B.V. All rights reserved.

Lavareda, G., A. de Calheiros Velozo, C. Nunes de Carvalho, and A. Amaral. "p/n junction depth control using amorphous silicon as a low temperature dopant source." THIN SOLID FILMS. 543 (2013): 122-124. Abstract

Phosphorus-doped amorphous silicon thin films, deposited at low temperatures by Plasma Enhanced Chemical Vapour Deposition were used as a dopant source on p-type c-Si substrates. A careful step of dehydrogenation was done in order to maintain the a-Si thin-film integrity. Subsequently, a fine-controlled drive-in of dopant, from the amorphous layer to the crystalline wafer was done, to form the p/n junction, using different time periods and temperatures. Dopant profiling in c-Si wafers as well as dopant concentration in a-Si: H films prior to diffusion, both measured by Secondary Ion Mass Spectrometry, are presented. Junction depths obtained are in the range of 98 nm to 2.4 mu m and surface concentrations are in the range of 1.1 x 10(21) to 4.3 x 10(20) at/cm(3). A dual diffusion mechanism explains the ``kink-and-tail{''} shape found for dopant profile. (C) 2013 Elsevier B.V. All rights reserved.

Lavareda, G., A. de Calheiros Velozo, C. Nunes de Carvalho, and A. Amaral. "p/n junction depth control using amorphous silicon as a low temperature dopant source." THIN SOLID FILMS. 543 (2013): 122-124. Abstract

Phosphorus-doped amorphous silicon thin films, deposited at low temperatures by Plasma Enhanced Chemical Vapour Deposition were used as a dopant source on p-type c-Si substrates. A careful step of dehydrogenation was done in order to maintain the a-Si thin-film integrity. Subsequently, a fine-controlled drive-in of dopant, from the amorphous layer to the crystalline wafer was done, to form the p/n junction, using different time periods and temperatures. Dopant profiling in c-Si wafers as well as dopant concentration in a-Si: H films prior to diffusion, both measured by Secondary Ion Mass Spectrometry, are presented. Junction depths obtained are in the range of 98 nm to 2.4 mu m and surface concentrations are in the range of 1.1 x 10(21) to 4.3 x 10(20) at/cm(3). A dual diffusion mechanism explains the ``kink-and-tail{''} shape found for dopant profile. (C) 2013 Elsevier B.V. All rights reserved.

de Calheiros Velozo, A., G. Lavareda, C. Nunes de Carvalho, and A. Amaral. "Thermal dehydrogenation of amorphous silicon: A time-evolution study." THIN SOLID FILMS. 543 (2013): 48-50. Abstract

A model is proposed to describe the decrease of H content in hydrogenated amorphous silicon (a-Si: H), during annealing at a fixed temperature. H content has been measured in several a-Si: H samples ( grown by plasma enhanced chemical vapor deposition) after being submitted to different annealing times at 400 degrees C. Obtained data has been fitted to the proposed model and initial diffusion coefficients of 3.2 x 10(-14) cm(2)/s for intrinsic films and 4.2 x 10(-14) cm(2)/s for n-type films were obtained. Reversely, H content evolution can be predicted during a thermal treatment if diffusion coefficients are previously known. (C) 2013 Elsevier B.V. All rights reserved.

de Calheiros Velozo, A., G. Lavareda, C. Nunes de Carvalho, and A. Amaral. "Thermal dehydrogenation of amorphous silicon: A time-evolution study." THIN SOLID FILMS. 543 (2013): 48-50. Abstract

A model is proposed to describe the decrease of H content in hydrogenated amorphous silicon (a-Si: H), during annealing at a fixed temperature. H content has been measured in several a-Si: H samples ( grown by plasma enhanced chemical vapor deposition) after being submitted to different annealing times at 400 degrees C. Obtained data has been fitted to the proposed model and initial diffusion coefficients of 3.2 x 10(-14) cm(2)/s for intrinsic films and 4.2 x 10(-14) cm(2)/s for n-type films were obtained. Reversely, H content evolution can be predicted during a thermal treatment if diffusion coefficients are previously known. (C) 2013 Elsevier B.V. All rights reserved.

R. Póvoa, Lourenço N., N. Horta, R. Santos-Tavares, and J. Goes Single-Stage Amplifiers with Gain Enhancement and Improved Energy-Efficiency using Voltage-Combiners. 21st IFIP/IEEE International Conference on Very Large Scale Integration (VLSI-SoC). Istanbul, Turkey: IFIP/IEEE, 2013.