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2016
Silva, João C., Alexandre A. Barros, Ivo M. Aroso, Dario Fassini, Tiago H. Silva, Rui L. Reis, and Ana Rita C. Duarte. "{Extraction of Collagen/Gelatin from the Marine Demosponge Chondrosia reniformis (Nardo, 1847) Using Water Acidified with Carbon Dioxide - Process Optimization}." Industrial and Engineering Chemistry Research. 55 (2016): 6922-6930. Abstract

Marine sponges are a rich source of natural bioactive compounds. One of the most abundant valuable products is collagen/gelatin, which presents an interesting alternative source for pharmaceutical and biomedical applications. We have previously proposed an innovative green technology for the extraction of collagen/gelatin from marine sponges based in water acidified with carbon dioxide. In this work, we have optimized the process operating conditions toward high yields and collagen quality as well as to reduce extraction procedure duration and energy consumption. The process extraction efficiency is higher than 50{%}, corresponding to a yield of approximately 10{%} of the sponge dry mass, obtained for mild operating conditions of 10 bar and 3 h. The extracted material was characterized by scanning electron microscopy (SEM), rheology, Fourier transformed infrared spectroscopy (FTIR), circular dichroism (CD), amino acid analysis, and SDS-PAGE. The extracts were found to be composed of highly pure mixtures of co...

Duarte, Ana Rita C., Devid Maniglio, Nuno Sousa, João F. Mano, Rui L. Reis, and Claudio Migliaresi. "{From honeycomb- to microsphere-patterned surfaces of poly(lactic acid) and a starch-poly(lactic acid) blend via the breath figure method.}." Journal of applied biomaterials {&} functional materials. 15 (2016). AbstractWebsite

BACKGROUND This study investigated the preparation of ordered patterned surfaces and/or microspheres from a natural-based polymer, using the breath figure and reverse breath figure methods. METHODS Poly(D,L-lactic acid) and starch poly(lactic acid) solutions were precipitated in different conditions - namely, polymer concentration, vapor atmosphere temperature and substrate - to evaluate the effect of these conditions on the morphology of the precipitates obtained. RESULTS The possibility of fine-tuning the properties of the final patterns simply by changing the vapor atmosphere was also demonstrated here using a range of compositions of the vapor phase. Porous films or discrete particles are formed when the differences in surface tension determine the ability of polymer solution to surround water droplets or methanol to surround polymer droplets, respectively. In vitro cytotoxicity was assessed applying a simple standard protocol to evaluate the possibility to use these materials in biomedical applications. Moreover, fluorescent microscopy images showed a good interaction of cells with the material, which were able to adhere on the patterned surfaces after 24 hours in culture. CONCLUSIONS The development of patterned surfaces using the breath figure method was tested in this work for the preparation of both poly(lactic acid) and a blend containing starch and poly(lactic acid). The potential of these films to be used in the biomedical area was confirmed by a preliminary cytotoxicity test and by morphological observation of cell adhesion.

Barros, A., S. Quraishi, M. Martins, P. Gurikov, R. Subrahmanyam, I. Smirnova, A. R. C. Duarte, and R. L. Reis. "{Hybrid Alginate-Based Cryogels for Life Science Applications}." Chemie-Ingenieur-Technik. 88 (2016). Abstract

© 2016 WILEY-VCH Verlag GmbH {&} Co. KGaA, Weinheim. This work presents a novel route toward porous scaffolds for tissue engineering and regenerative medicine (TERM) applications. Hybrid cryogels with gelatin, gellan gum, carboxymethylcellulose, and lignin were prepared by a two-step process. Textural properties of the cryogels were analyzed by SEM and micro-computed tomography. The results indicated that rapid freezing retained sample shape and yielded macroporous materials. The mechanical properties of the cryogels were characterized in compression mode. Cytotoxicity studies indicated that the hybrid-alginate cryogels did not present cytotoxicity and have the potential to be used in TERM.

Barros, A. A., I. M. Aroso, T. H. Silva, J. F. Mano, A. R. C. Duarte, and R. L. Reis. "{In vitro bioactivity studies of ceramic structures isolated from marine sponges}." Biomedical Materials (Bristol). 11 (2016). Abstract

© 2016 IOP Publishing Ltd. In this work, we focused on the potential of bioceramics from different marine sponges - namely Petrosia ficiformis, Agelas oroides and Chondrosia reniformis - for novel biomedical/industrial applications. The bioceramics from these sponges were obtained after calcination at 750 °C for 6 h in a furnace. The morphological characteristics were evaluated by scanning electron microscopy (SEM). The in vitro bioactivity of the bioceramics was evaluated in simulated body fluid (SBF) after 14 and 21 d. Observation of the bioceramics by SEM after immersion in SBF solution, coupled with spectroscopic elemental analysis (EDS), showed that the surface morphology was consistent with a calcium-phosphate (Ca/P) coating, similar to hydroxyapatite crystals (HA). Evaluation of the characteristic peaks of Ca/P crystals by Fourier transform infrared spectroscopy and x-ray diffraction further confirmed the existence of HA. Cytotoxicity studies were carried out with the different ceramics and these were compared with a commercially available Bioglass ® . In vitro tests demonstrated that marine bioceramics from these sponges are non-cytotoxic and have the potential to be used as substitutes for synthetic Bioglass ® .

Lopes, A., A. Gabriel, J. Machado, P. Ribeiro, R. Gomes, João M. P. Coelho, C. O. Silva, C. P. Reis, J. P. Santos, and P. Vieira. "{Multiple Source Phototherapy in Breast Cancer: A Viability Study}." 9th International Conference on Biomedical Electronics and Devices. SCITEPRESS - Science and and Technology Publications, 2016. 247-250. Abstract
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Reifarth, R., et al. "{Nuclear astrophysics with radioactive ions at FAIR}." Vol. 665. Journal of Physics: Conference Series, 2016. 012044. Abstract
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2015
Pinho, S. T. R., P. Rodrigues, R. F. S. Andrade, H. Serra, J. S. Lopes, and M. G. M. Gomes. "Impact of tuberculosis treatment length and adherence under different transmission intensities." THEORETICAL POPULATION BIOLOGY. 104 (2015): 68-77. Abstract

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Rahangdale, H. V., D. Mitra, M. Guerra, J. P. Santos, and S. Saha. "Subshell resolved inner shell ionization cross-sections of High Z elements by electron impact." Journal of Physics: Conference Series. 635 (2015): 052001-2. AbstractWebsite
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Inácio, Micael M. G., André F. O. Almeida, Duarte M. V. Faria, Válter J. G. Lúcio, and António Pinho Ramos. "Punching of high strength concrete flat slabs without shear reinforcement." Engineering Structures. 103 (2015): 275-284. AbstractWebsite

The experimental research carried out to study the punching behavior of high strength concrete (HSC) flat slabs is reported in the present work. Three flat slab specimens were cast using HSC and another one with normal strength concrete (NSC), to be used as a reference slab. The HSC mix presented a compressive strength of about 130MPa, with a basalt coarse aggregate. The tested specimens were square with 1650mm side and 125mm thickness. The longitudinal reinforcement ratio varied between 0.94{%} and 1.48{%}. The experimental results show that the use of HSC led to a significant load capacity increase when compared with the reference model made with NSC. Furthermore, the experimental results also indicated that as the longitudinal reinforcement ratio increased, the punching capacity also increased. The results obtained in this set of experimental tests and others collected from the literature were compared with the code provisions by EC2, MC2010 and ACI 318-11.

AC, Baptista, Botas AM, Almeida AP, Nicolau AT, Falcão BP, Soares MJ, Leitão JP, Martins R, Borges JP, and Ferreira I. "Down conversion photoluminescence on PVP/Ag-nanoparticles electrospun composite fibers." Optical Materials. 39 (2015): 278-281. Abstract
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Machado, J., J. Adamczewski-Musch, A. Blanco, K. Boretzky, P. Cabanelas, L. Cartegni, Ferreira R. Marques, P. Fonte, J. Fruehauf, D. Galaviz, M. Heil, A. Henriques, G. Ickert, D. Körper, L. Lopes, M. Palka, A. Pereira, D. Rossi, H. Simon, P. Teubig, M. Traxler, P. Velho, S. Altstadt, L. Atar, T. Aumann, D. Bemmerer, C. Caesar, A. Charpy, Z. Elekes, E. Fiori, I. Gasparic, J. Gerbig, K. Göbel, T. Heftrich, M. Heine, A. Heinz, M. Holl, A. Ignatov, J. Isaak, H. Johansson, A. Kelic-Heil, C. Lederer, S. Lindberg, B. Löher, J. Marganiec, M. Martensson, T. Nilsson, V. Panin, S. Paschalis, M. Petri, R. Plag, M. Pohl, G. Rastrepina, R. Reifarth, T. P. Reinhardt, M. Röder, D. Savran, H. Scheit, P. Schrock, J. Silva, D. Stach, F. Strannerdahl, R. Thies, A. Wagner, F. Wamers, and M. Weigand. "{Performance of timing Resistive Plate Chambers with protons from 200 to 800 MeV}." Journal of Instrumentation. 10 (2015): C01043. AbstractWebsite
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Pavan, Michele, Sven R??hle, Adam Ginsburg, David A. Keller, Hannah-Noa Noa Barad, Paolo M. Sberna, Daniela Nunes, Rodrigo Martins, Assaf Y. Anderson, Arie Zaban, Elvira Fortunato, Sven Rühle, Adam Ginsburg, David A. Keller, Hannah-Noa Noa Barad, Paolo M. Sberna, Daniela Nunes, Rodrigo Martins, Assaf Y. Anderson, Arie Zaban, and Elvira Fortunato. "{TiO2/Cu2O all-oxide heterojunction solar cells produced by spray pyrolysis}." Solar Energy Materials and Solar Cells. 132 (2015): 549-556. AbstractWebsite

Here we present for the first time a TiO2/Cu2O all-oxide heterojunction solar cell entirely produced by spray pyrolysis onto fluorine doped tin oxide (FTO) covered glass substrates, using silver as a back contact. A combinatorial approach was chosen to investigate the impact of the TiO2 window layer and the Cu2O light absorber thicknesses. We observe an open circuit voltage up to 350 mV and a short circuit current density which is strongly dependent of the Cu2O thickness, reaching a maximum of {\~{}}0.4 mA/cm2. Optical investigation reveals that a thickness of 300 nm spray pyrolysis deposited Cu2O is sufficient to absorb most photons with an energy above the symmetry allowed optical transition of 2.5 eV, indicating that the low current densities are caused by strong recombination in the absorber that consists of small Cu2O grains.

Blanco, A., J. Adamczewski-Musch, K. Boretzky, P. Cabanelas, L. Cartegni, Ferreira R. Marques, P. Fonte, J. Fruehauf, D. Galaviz, M. Heil, A. Henriques, G. Ickert, D. Körper, L. Lopes, M. Palka, A. Pereira, D. Rossi, H. Simon, P. Teubig, M. Traxler, P. Velho, S. Altstadt, L. Atar, T. Aumann, D. Bemmerer, C. Caesar, A. Charpy, Z. Elekes, E. Fiori, I. Gasparic, J. Gerbig, K. Göbel, T. Heftrich, M. Heine, A. Heinz, M. Holl, A. Ignatov, J. Isaak, H. Johansson, A. Kelic-Heil, C. Lederer, S. Lindberg, B. Löher, J. Machado, J. Marganiec, M. Martensson, T. Nilsson, V. Panin, S. Paschalis, M. Petri, R. Plag, M. Pohl, G. Rastrepina, R. Reifarth, T. P. Reinhardt, M. Röder, D. Savran, H. Scheit, P. Schrock, J. Silva, D. Stach, F. Strannerdahl, R. Thies, A. Wagner, F. Wamers, and M. Weigand. "{Performance of timing resistive plate chambers with relativistic neutrons from 300 to 1500 MeV}." Journal of Instrumentation. 10 (2015): C02034. AbstractWebsite
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Morais, Ana Rita C., Joana Vaz Pinto, Daniela Nunes, Luísa B. Roseiro, Maria Conceição Oliveira, Elvira Fortunato, and Rafał Bogel-Łukasik. "{Imidazole: Prospect Solvent for Lignocellulosic Biomass Fractionation and Delignification}." ACS Sustainable Chemistry {&} Engineering (2015). AbstractWebsite
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Foth, Christian, Serjoscha W. Evers, Ben Pabst, Octávio Mateus, Alexander Flisch, Mike Patthey, and Oliver W. M. Rauhut. "New insights into the lifestyle of \\textitAllosaurus (Dinosauria: Theropoda) based on another specimen with multiple pathologies." PeerJ. 3 (2015): e940. AbstractWebsite

Adult large-bodied theropods are often found with numerous pathologies. A large, almost complete, probably adult \\textitAllosaurus specimen from the Howe Stephens Quarry, Morrison Formation (Late Kimmeridgian–Early Tithonian), Wyoming, exhibits multiple pathologies. Pathologic bones include the left dentary, two cervical vertebrae, one cervical and several dorsal ribs, the left scapula, the left humerus, the right ischium, and two left pedal phalanges. These pathologies can be classified as follows: the fifth cervical vertebra, the scapula, several ribs and the ischium are probably traumatic, and a callus on the shaft of the left pedal phalanx II-2 is probably traumatic-infectious. Traumatically fractured elements exposed to frequent movement (e.g., the scapula and the ribs) show a tendency to develop pseudarthroses instead of a callus. The pathologies in the lower jaw and a reduced extensor tubercle of the left pedal phalanx II-2 are most likely traumatic or developmental in origin. The pathologies on the fourth cervical are most likely developmental in origin or idiopathic, that on the left humerus could be traumatic, developmental, infectious or idiopathic, whereas the left pedal phalanx IV-1 is classified as idiopathic. With exception of the ischium, all as traumatic/traumatic-infectious classified pathologic elements show unambiguous evidences of healing, indicating that the respective pathologies did not cause the death of this individual. Alignment of the scapula and rib pathologies from the left side suggests that all may have been caused by a single traumatic event. The ischial fracture may have been fatal. The occurrence of multiple lesions interpreted as traumatic pathologies again underlines that large-bodied theropods experienced frequent injuries during life, indicating an active predatory lifestyle, and their survival perhaps supports a gregarious behavior for \\textitAllosaurus. Alternatively, the frequent survival of traumatic events could be also related to the presence of non-endothermic metabolic rates that allow survival based on sporadic food consumption or scavenging behavior. Signs of pathologies consistent with infections are scarce and locally restricted, indicating a successful prevention of the spread of pathogens, as it is the case in extant reptiles (including birds).

Caeiro, Frederico Almeida Gião Gonçalves, Ayana Maria Xavier Furtado Mateus, and Luís Pedro Carneiro Ramos. "Extreme value analysis of the sea levels in Venice." PROCEEDINGS OF THE INTERNATIONAL CONFERENCE OF NUMERICAL ANALYSIS AND APPLIED MATHEMATICS 2014. AIP Conference Proceedings. American Institute of Physics Inc., 2015. Abstract

The number of floods in the city of Venice has increased substantially in the last decades and can be explained bythe sea level rise and land subsidence. Using Statistics of Extremes we shall model the extreme behaviour of the sea level inVenice and quantify risk through the estimation of important parameters such as return periods of high levels.The number of floods in the city of Venice has increased substantially in the last decades and can be explained bythe sea level rise and land subsidence. Using Statistics of Extremes we shall model the extreme behaviour of the sea level inVenice and quantify risk through the estimation of important parameters such as return periods of high levels.

Ghisolfi, A., F. Condello, C. Fliedel, V. Rosa, and P. Braunstein. "Facile and Room-Temperature Activation of Csp3-Cl Bonds by Cheap and Air-Stable Nickel(II) Complexes of (N-Thioether) DPPA-Type Ligands." Organometallics. 34.11 (2015): 2255-2260. AbstractWebsite
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Foth, Christian, Serjoscha Evers, Ben Pabst, Octávio Mateus, Alexander Flisch, Mike Patthey, and Oliver W. M. Rauhut. "New insights into the lifestyle of Allosaurus (Dinosauria: Theropoda) based on another specimen with multiple pathologies." PeerJ PrePrints. 3 (2015): e824v1. Abstractfoth_et_al_2015_peerj-preprints-824.pdfWebsite

Adult large-bodied theropods are often found with numerous pathologies. A large, almost complete, probably adult Allosaurus specimen from the Howe Stephens Quarry, Morrison Formation (Late Kimmeridgian–Early Tithonian), Wyoming, shows multiple pathologies. Pathologic bones include the left dentary, two cervical vertebrae, one cervical and several dorsal ribs, the left scapula, the left humerus, right ischium, and two left pedal phalanges. These pathologies can be classified as follows: the fifth cervical vertebra, the scapula, several ribs and the ischium are traumatic, and a callus on the shaft of the left pedal phalanx II-2 is traumatic-infectious. Traumatically fractured elements exposed to frequent movement (e.g. the scapula and the ribs) show a tendency to develop pseudarthroses instead of callus healing. The pathologies in the lower jaw and a reduced flexor tubercle of the left pedal phalanx II-2 are most likely traumatic or developmental in origin. The pathologies on the fourth cervical are most likely developmental in origin or idiopathic, that on the left humerus is infectious or idiopathic, whereas left pedal phalanx IV-1 is classified as idiopathic. With exception of the ischium, all traumatic / traumatic-infectious pathologic elements show unambiguous evidences of healing, indicating that the respective pathologies did not cause the death of this individual. Alignment of the scapula and rib pathologies from the left side suggests that all may have been caused by a single traumatic event. The ischial fracture may have been fatal. The occurrence of multiple traumatic pathologies again underlines that large-bodied theropods experienced frequent injuries during life, indicating an active predatory lifestyle, and their survival perhaps supports a gregarious behavior for Allosaurus. Signs of infections are scarce and locally restricted, indicating a successful prevention of the spread of pathogens, as it is the case in extant reptiles (including birds).

Fliedel, C., V. Rosa, F. M. Alves, A. M. Martins, T. Avilés, and S. Dagorne. "P,O-Phosphinophenolate zinc(ii) species: Synthesis, structure and use in the ring-opening polymerization (ROP) of lactide, ε-caprolactone and trimethylene carbonate." Dalton Transactions. 44.27 (2015): 12376-12387. AbstractWebsite
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Avó, João, M. T. Cidade, Vincent Rodriguez, João C. Lima, and Jorge A. Parola. "Photorheological Ionic Liquids." 119.22 (2015): 6680-6685. Abstract
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Kauf, T., V. Rosa, C. Fliedel, R. Pattacini, N. Deibel, T. Avilés, B. Sarkar, and P. Braunstein. "Reactivity of TCNE and TCNQ derivatives of quinonoid zwitterions with Cu(I)." Dalton Transactions. 44.12 (2015): 5441-5450. AbstractWebsite
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Xing, Lida, Martin G. Lockley, Daniel Marty, Jianping Zhang, Yan Wang, Hendrik Klein, Richard T. McCrea, Lisa G. Buckley, Matteo Belvedere, Octávio Mateus, Gerard D. Gierliński, Laura Piñuela, Scott W. Persons, IV, Fengping Wang, Hao Ran, Hui Dai, and Xianming Xie. "An Ornithopod-Dominated Tracksite from the Lower Cretaceous Jiaguan Formation (Barremian–Albian) of Qijiang, South-Central China: New Discoveries, Ichnotaxonomy, Preservation and Palaeoecology." PLoS ONE. 10 (2015): e0141059. Abstractlida_et_al_2015_an_ornithopod-dominated_tracksite_from_the.pdfWebsite

The historically-famous Lotus Fortress site, a deep 1.5–3.0-meter-high, 200-meter-long horizonal notch high up in near-vertical sandstone cliffs comprising the Cretaceous Jiaguan Formation, has been known since the 13th Century as an impregnable defensive position. The site is also extraordinary for having multiple tetrapod track-bearing levels, of which the lower two form the floor of part of the notch, and yield very well preserved asseamblages of ornithopod, bird (avian theropod) and pterosaur tracks. Trackway counts indicate that ornithopods dominate (69%) accounting for at least 165 trackmakers, followed by bird (18%), sauropod (10%), and pterosaur (3%). Previous studies designated Lotus Fortress as the type locality of Caririchnium lotus and Wupus agilis both of which are recognized here as valid ichnotaxa. On the basis of multiple parallel trackways both are interpreted as representing the trackways of gregarious species. C. lotus is redescribed here in detail and interpreted to indicate two age cohorts representing subadults that were sometimes bipedal and larger quadrupedal adults. Two other previously described dinosaurian ichnospecies, are here reinterpreted as underprints and considered nomina dubia. Like a growing number of significant tetrapod tracksites in China the Lotus Fortress site reveals new information about the composition of tetrapod faunas from formations in which the skeletal record is sparse. In particular, the site shows the relatively high abundance of Caririchium in a region where saurischian ichnofaunas are often dominant. It is also the only site known to have yielded Wupus agilis. In combination with information from other tracksites from the Jiaguan formation and other Cretaceous formations in the region, the track record is proving increasingly impotant as a major source of information on the vertebrate faunas of the region. The Lotus Fortress site has been developed as a spectacular, geologically-, paleontologically- and a culturally-significant destination within Qijiang National Geological Park.

Ramalhete, Inês, Miguel P. Amado, and Hugo Farias. "Criteria Framework for the Conception of an Adaptive Housing Model for Sub-Saharan Region." CONFERENCE: HOUSING – A CRITICAL PERSPECTIVE Architecture_MPS. Liverpool John Moores University Liverpool: Liverpool University, 2015.