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2014
Contreras, Javier, Rodrigo Martins, Pawel Wojcik, Sergej Filonovich, Hugo Aguas, Luis Gomes, Elvira Fortunato, and Isabel Ferreira. "Color sensing ability of an amorphous silicon position sensitive detector array system." Sensors and Actuators A: Physical. 205 (2014): 26-37. Abstract
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Mateus, Octávio. "Comparison of modern and fossil Crocodylomorpha eggs and contribution to the oophylogeny of Amniota." Annual Meeting of the European Association of Vertebrate Palaeontologists. , p. 192, Regione Piemonte: European Association of Vertebrate Palaeontologists. Museo Regionale di Scienze Naturali. 2014. Abstract
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Araújo, João, Janusz Konieczny, and António Malheiro. "Conjugation in semigroups." J. Algebra. 403 (2014): 93-134. AbstractWebsite
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Russo, J., O. Mateus, A. Balbino, and M. Marzola. "Crocodylomorph eggs and eggshells from the Lourinhã Fm. (Upper Jurassic), Portugal." Comunica\\c cões Geológicas. 101, Especial I (2014): 563-566. Abstract
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Russo, J., O. Mateus, A. Balbino, and M. Marzola. "Crocodylomorph eggs and eggshells from the Lourinhã Fm. (Upper Jurassic), Portugal." Comunica\\c cões Geológicas. 101, Especial I (2014): 563-566. Abstract
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Russo, J., O. Mateus, A. Balbino, and M. Marzola. "Crocodylomorph eggs and eggshells from the Lourinhã Fm. (Upper Jurassic), Portugal." Comunica\\c cões Geológicas. 101, Especial I (2014): 563-566. Abstract

We here present fossil Crocodylomorpha eggshells from the Upper Jurassic Lourinhã Formation of Portugal, recovered from five sites: one nest from Cambelas with 13 eggs, and three partial eggs and various fragments from, Paimogo N (I), Paimogo S (II), Casal da Rola, and Peralta. All specimens but the nest were found in association with dinosaur egg material. Our research reveals that on a micro- and ultrastructural analysis, all samples present the typical characters consistent with crocodiloid eggshell morphotype, such as the shell unit shape, the organization of the eggshell layers, and the triangular blocky extinction observed with crossed nicols. We assign the material from the Lourinhã Formation to the oofamily Krokolithidae, making it the oldest crocodylomorph eggs known so far, as well as the best record for eggs of non- crocodylian crocodylomorphs. Furthermore, our study indicates that the basic structure of crocodiloid eggshells has remained stable since at least the Upper Jurassic.

Soares, R. S. a, R. C. C. a Monteiro, A. A. S. a Lopes, M. M. R. A. a Lima, B. A. b Sava, and M. b Elisa. "Crystallization and microstructure of Eu3 +-doped lithium aluminophosphate glass." Journal of Non-Crystalline Solids. 403 (2014): 9-17. AbstractWebsite

A transparent Eu3 +-doped lithium aluminophosphate glass was prepared by melt-quenching technique. The thermal behavior of the glass was investigated by differential thermal analysis (DTA), the structure was studied by X-ray diffraction (XRD) and the morphology was observed by optical polarization microscopy and scanning electron microscopy (SEM). The activation energy of glass transition and the activation energy of crystallization and Avrami exponent have been evaluated under non-isothermal conditions from the data obtained by DTA at different heating rates. DTA curves exhibited an endothermic peak associated with the glass transition and two exothermic peaks. The mean value calculated for the activation energy of glass transition was 545 kJ mol- 1. The activation energy of crystallization was   400 kJ mol- 1 for the first exothermic peak and   170 kJ mol- 1 for the second peak. The Avrami exponent was   1 for both peaks indicating surface crystallization. XRD results showed that the main crystalline phase, aluminum metaphosphate, Al(PO3)3, and aluminum phosphate, AlPO4, were formed together with lithium barium phosphate, Li 3Ba(PO3)7, during the first exothermic peak and together with barium pyrophosphate, Ba2P2O7, during the second peak. Morphological study of heat-treated glass samples revealed microstructural features that confirmed a surface crystallization process. © 2014 Elsevier B.V.

Lopes, A. A. S. a, R. C. C. a Monteiro, R. S. a Soares, M. M. R. A. a Lima, and M. H. V. b Fernandes. "Crystallization kinetics of a barium-zinc borosilicate glass by a non-isothermal method." Journal of Alloys and Compounds. 591 (2014): 268-274. AbstractWebsite

The crystallization kinetics of a glass with a molar composition 40BaO-20ZnO-30B2O3-10SiO2 was investigated. The kinetic parameters, activation energy for crystallization (Ec) and Avrami exponent (n), were evaluated under non-isothermal conditions using the results obtained by differential thermal analysis (DTA) performed at different heating rates. DTA curves exhibited two overlapping exothermic peaks associated with the crystallization of the glass. Barium borate (BaB4O 7) was the first crystalline phase to be formed and it was followed by the formation of barium zinc silicate (BaZnSiO4), as identified by XRD. For the first exothermic peak, when the fraction of crystallization (χ) increased from 0.1 to 0.9, the local activation energy (E c(χ)) decreased from 700 to 500 kJ/mol, while for the second exothermic peak, Ec(χ) slightly increased from 490 to 570 kJ/mol. For the range of 0.1 < χ < 0.9, the local Avrami exponent (n(χ)) increased from ∼1 to 1.4 for the first exothermic peak and it decreased from ∼1.7 to 1.4 for the second exothermic peak. Observation by SEM of the microstructure of sintered glass samples revealed that crystallization started at the surface of glass particles, with growth of lamellar crystallites, that together with some quasi-spherical nano-sized crystallites progressed towards the inside of the glass at the highest sintering temperatures. The change of the local activation energy with the fraction of crystallization suggested that a multi-step kinetic reaction took place during sintering and crystallization of the glass. © 2013 Elsevier B.V. All rights reserved.

Soares, R. S., R. C. C. Monteiro, M. M. R. A. Lima, and R. J. C. Silva. "Crystallization of lithium disilicate-based multicomponent glasses - Effect of silica/lithia ratio." Ceramics International. 41 (2014): 317-324. AbstractWebsite

Two glass compositions were prepared from the system SiO2-Li2O-K2O-ZrO2-P2O5 with different SiO2/Li2O ratio (2.39 and 3.39) and the crystallization behavior was investigated by differential thermal analysis (DTA), X-ray diffraction (XRD) and scanning electron microscopy (SEM). The crystallization kinetic parameters (activation energy of crystallization and Avrami exponent) were evaluated by different methods from the data obtained by DTA performed at different heating rates. For both glasses, two exothermic peaks were observed in the DTA curves, and the crystallization peak temperatures increased with SiO2/Li2O ratio. XRD analysis revealed that the first peak corresponds to the crystallization of lithium metasilicate (Li2SiO3) and the second to the formation of lithium disilicate (Li2Si2O5). After heating the glasses at a temperature above the second crystallization peak (900 °C), both Li2Si2O5 and Li2SiO3 were found in samples having the lowest SiO2/Li2O ratio, whereas no Li2SiO3 was detected in samples with the highest SiO2/Li2O ratio. For both glasses, the value obtained by different methods for the activation energy of crystallization was in the range of 225-275 kJ mol-1 for the first exothermic peak and in the range of 425-500 kJ mol-1 for the second peak. The estimated Avrami exponent was close to 1 for the first exothermic peak, indicating surface crystallization, and close to 3 for the second exothermic peak, suggesting volume crystallization. This was confirmed by the morphological study made by SEM that showed needle-like crystals in the microstructure of samples with lithium metasilicate and granular crystals in the microstructure of samples having lithium disilicate. © 2014 Elsevier Ltd and Techna Group S.r.l. All rights reserved.

Hendrickx, Christophe, Octávio Mateus, and Ricardo Araújo. "The dentition of Megalosauridae (Theropoda: Dinosauria)." {APP} (2014). AbstractWebsite
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Xavier, J., M. Oliveira, J. J. L. Morais, and M. F. S. F. de Moura. "Determining mode İI\} cohesive law of Pinus pinaster by combining the end-notched flexure test with digital image correlation." Construction and Building Materials. 71 (2014): 109-115. Abstract

Abstract This work addresses the direct identification of cohesive law of Pinus pinaster in mode II. The end-notched flexure (ENF) test is selected for mode İI\} loading. The strain energy release rate in mode İI\} (GII) is determined according to the compliance-based beam method (CBBM) by processing the global load�displacement curve, without requirements to monitor the crack length during test. The fracture test is coupled with digital image correlation (DIC) for the local measurement of the crack tip opening displacement in mode İI\} (wII). Using a direct method, the cohesive law in mode İI\} (sII�wII) is determined by differentiating the GII�wII relationship. The procedure is validated from both numerical, using finite element analyses including cohesive zone modelling, and experimental approaches. The methodology and accuracy on this reconstruction is discussed. It is concluded that the proposed data reduction scheme is suitable for assessing the cohesive law of P. pinaster in mode II.

Mateus, Octávio. "Dinosaur taphonomy in the Lourinhã Formation (Late Jurassic, Portugal)." International Meeting on Taphonomy and Fossilization. 2014. 60-61. Abstract
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Xavier, J., M. Oliveira, P. Monteiro, J. J. L. Morais, and M. F. S. F. Moura. "Direct Evaluation of Cohesive Law in Mode I of Pinus pinaster by Digital Image Correlation." Experimental Mechanics. 54 (2014): 829-840. AbstractWebsite
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Heleno, R., C. Garcia, P. Jordano, A. Traveset, J. M. Gómez, N. Blüthgen, J. Memmott, M. Moora, J. Cerdeira, S. Rodríguez-Echeverría, H. Freitas, and J. M. Olesen. "Ecological networks: Delving into the architecture of biodiversity." Biology Letters. 10 (2014). Abstract
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Mateus, Octávio. "Eggs and eggshells of crocodylomorpha from the Late Jurassic of Portugal." Journal of Vertebrate Paleontology. Program and Abstracts, 2014 (2014): 218. Abstract
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Schmeisser, Dieter, Joerg Haeberle, Pedro Barquinha, Diana Gaspar, Luis Pereira, Rodrigo Martins, and Elvira Fortunato. "Electronic structure of amorphous ZnO films." Physica Status Solidi C: Current Topics in Solid State Physics, Vol 11, No 9-10. Eds. M. Godlewski, and A. Zakrzewski. Vol. 11. Physica Status Solidi C-Current Topics in Solid State Physics, 11. 2014. 1476-1480. Abstract
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Araujo-Martins, J., Carreiro P. Martins, J. Viegas, D. Aelenei, MM Cano, JP Teixeira, P. Paixão, AL Papoila, P. Leiria-Pinto, C. Pedro, and others. "Environment and Health in Children Day Care Centres (ENVIRH)–Study rationale and protocol." Revista portuguesa de pneumologia. 20 (2014): 311-323. Abstract

Background Indoor air quality (IAQ) is considered an important determinant of human health. The association between exposure to volatile organic compounds, particulate matter, house dust mite, molds and bacteria in day care centers (DCC) is not completely clear. The aim of this project was to study these effects. Methods ? study design This study comprised two phases. Phase I included an evaluation of 45 DCCs (25 from Lisbon and 20 from Oporto, targeting 5161 children). In this phase, building characteristics, indoor CO2 and air temperature/relative humidity, were assessed. A children's respiratory health questionnaire derived from the ISAAC (International Study on Asthma and Allergies in Children) was also distributed. Phase II encompassed two evaluations and included 20 DCCs selected from phase I after a cluster analysis (11 from Lisbon and 9 from Oporto, targeting 2287 children). In this phase, data on ventilation, IAQ, thermal comfort parameters, respiratory and allergic health, airway inflammation biomarkers, respiratory virus infection patterns and parental and child stress were collected. Results In Phase I, building characteristics, occupant behavior and ventilation surrogates were collected from all DCCs. The response rate of the questionnaire was 61.7% (3186 children). Phase II included 1221 children. Association results between DCC characteristics, IAQ and health outcomes will be provided in order to support recommendations on IAQ and children's health. A building ventilation model will also be developed. Discussion This paper outlines methods that might be implemented by other investigators conducting studies on the association between respiratory health and indoor air quality at DCC.

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.

Mateus, O., R. J. Butler, S. L. Brusatte, J. H. Whiteside, and J. S. Steyer. "The first phytosaur (Diapsida, Archosauriformes) from the Late Triassic of the Iberian Peninsula." Journal of Vertebrate Paleontology. 34 (2014): 970-975. Abstract
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Mateus, O., R. J. Butler, S. L. Brusatte, J. H. Whiteside, and J. S. Steyer. "The first phytosaur (Diapsida, Archosauriformes) from the Late Triassic of the Iberian Peninsula." Journal of Vertebrate Paleontology. 34 (2014): 970-975. Abstract
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Strganac, C., LL Jacobs, M. J. Polcyn, O. Mateus, TS Myers, J. Salminen, S. R. May, R. Araújo, KM Ferguson, A. O. Gon?alves, ML Morais, AS Schulp, and T. da Silva Tavares. "Geological setting and paleoecology of the Upper Cretaceous Bench 19 Marine Vertebrate Bonebed at Bentiaba, Angola." Geologie en Mijnbouw/Netherlands Journal of Geosciences. 94 (2014): 121-136. Abstract
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Mateus, Octávio. "Gigantic jurassic predators." 52 Things You Should Know About Palaeontology. Ed. Agile Libre. Agile Libre, 2014. 56-57. Abstract
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