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2015
Nunes, D., L. Santos, P. Duarte, A. Pimentel, JV Pinto, P. Barquinha, P. A. Carvalho, E. Fortunato, and R. Martins. "Room Temperature Synthesis of Cu2O Nanospheres: Optical Properties and Thermal Behavior." Microscopy and Microanalysis. 21.01 (2015): 11. Abstract

The present work reports a simple and easy wet chemistry synthesis of cuprous oxide (Cu2O) nanospheres at room temperature without surfactants and using different precursors. Structural characterization was carried out by X-ray diffraction, transmission electron microscopy, and scanning electron microscopy coupled with focused ion beam and energy-dispersive X-ray spectroscopy. The optical band gaps were determined from diffuse reflectance spectroscopy. The photoluminescence behavior of the as-synthesized nanospheres showed significant differences depending on the precursors used. The Cu2O nanospheres were constituted by aggregates of nanocrystals, in which an on/off emission behavior of each individual nanocrystal was identified during transmission electron microscopy observations. The thermal behavior of the Cu2O nanospheres was investigated with in situ X-ray diffraction and differential scanning calorimetry experiments. Remarkable structural differences were observed for the nanospheres annealed in air, which turned into hollow spherical structures surrounded by outsized nanocrystals. FAU - Nunes, Daniela

Santos, T. C., A. R. De Oliveira, J. M. Dantas, C. A. Salgueiro, and C. M. Cordas. "Thermodynamic and kinetic characterization of PccH, a key protein in microbial electrosynthesis processes in Geobacter sulfurreducens." Biochimica et Biophysica Acta - Bioenergetics. 1847.10 (2015): 1113-1118. 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.

Vale, Tiago, Ricardo J. Dias, João A. Silva, and João M. Lourenço. "Execução concorrente e determinista de transações." Proceedings of INForum Simpósio de Informática. INForum 2015. Covilhã, Portugal 2015. Abstractinforum15-pot.pdf

Neste artigo apresentamos um protocolo de controlo de concorrência que garante que a execução concorrente de transações é equivalente à sua execução sequencial por uma ordem predefinida. Isto permite executar programas que usam transações de forma determinista. O protocolo (1) permite, pela primeira vez, a execução determinista de programas que usam memória transacional por hardware; e (2) garante a execução determinista de programas que usam memória transacional por software com um desempenho claramente superior ao estado da arte.

Petrova, K. T., S. S. Dey, and M. T. Barros. "Formation of spherical and core-shell polymeric microparticles from glycopolymers." Carbohydr. Polym. 125 (2015): 281-287. DOI: 10.1016/j.carbpol.2015.02.052.
Dias, Ricardo J., Tiago M. Vale, and João M. Lourenço. "Framework Support for the Efficient Implementation of Multi-version Algorithms." Transactional Memory. Foundations, Algorithms, Tools, and Applications. Eds. Rachid Guerraoui, and Paolo Romano. Vol. 8913. Lecture Notes in Computer Science, 8913. Springer International Publishing, 2015. 166-191. Abstracttransactional_memory-dias_vale_lourenco.pdf

Software Transactional Memory algorithms associate metadata with the memory locations accessed during a transactions lifetime. This metadata may be stored in an external table and accessed by way of a function that maps the address of each memory location with the table entry that keeps its metadata (this is the out-place or external scheme); or alternatively may be stored adjacent to the associated memory cell by wrapping them together (the in-place scheme). In transactional memory multi-version algorithms, several versions of the same memory location may exist. The efficient implementation of these algorithms requires a one-to-one correspondence between each memory location and its list of past versions, which is stored as metadata. In this chapter we address the matter of the efficient implementation of multi-version algorithms in Java by proposing and evaluating a novel in-place metadata scheme for the Deuce framework. This new scheme is based in Java Bytecode transformation techniques and its use requires no changes to the application code. Experimentation indicates that multi-versioning STM algorithms implemented using our new in-place scheme are in average 6 × faster than when implemented with the out-place scheme.

Cardoso, Tiago, João Delgado, and José Barata. "Hand gesture recognition towards enhancing accessibility." Procedia Computer Science. 67 (2015): 419-429. Abstract

Human-Computer-Interaction (HCI) is a key topic on the Accessibility area, namely in what concerns a Smart-City environment, where humans have to interact with artefacts spread all around one particular city. In the last decade HCI has experienced a significant evolution towards a desired fully natural user interface, for example in what concerns the ability to recognize a wide range of hand gestures in real-time. Some efforts have lately been made in the hardware sector in order to deploy sensors that may gather information about the human body movements, as detailed as possible. One example of this effort is the Kinect Sensor from Microsoft. Nevertheless, although these solutions provide a solution for the body movement, they lack on the details, namely the hands, given their small dimension compared to the body as a whole. In other words, the SDKs provided by the vendors of these devices usually lack on the needed details concerning hand movements that would be needed for an accurate hand gesture recognition implementation. This paper presents an extension to the Kinect SDK based on a contour analysis for the estimation of the hand position. This algorithms are then used to provide the creation of a gesture library that might be used afterwards.

Sousa, D. G., R. J. Dias, C. Ferreira, and J. M. Lourenço. "Preventing Atomicity Violations with Contracts." ArXiv e-prints (2015). Abstract1505.02951v1-dsousa.pdfWebsite

Software developers are expected to protect concurrent accesses to shared regions of memory with some mutual exclusion primitive that ensures atomicity properties to a sequence of program statements. This approach prevents data races but may fail to provide all necessary correctness properties.The composition of correlated atomic operations without further synchronization may cause atomicity violations. Atomic violations may be avoided by grouping the correlated atomic regions in a single larger atomic scope. Concurrent programs are particularly prone to atomicity violations when they use services provided by third party packages or modules, since the programmer may fail to identify which services are correlated. In this paper we propose to use contracts for concurrency, where the developer of a module writes a set of contract terms that specify which methods are correlated and must be executed in the same atomic scope. These contracts are then used to verify the correctness of the main program with respect to the usage of the module(s). If a contract is well defined and complete, and the main program respects it, then the program is safe from atomicity violations with respect to that module. We also propose a static analysis based methodology to verify contracts for concurrency that we applied to some real-world software packages. The bug we found in Tomcat 6.0 was immediately acknowledged and corrected by its development team.

Corvo, Marta C., João Sardinha, Teresa Casimiro, Graciane Marin, Marcus Seferin, Sandra Einloft, Sonia C. Menezes, Jairton Dupont, and Eurico J. Cabrita. "A rational approach to sustainable CO2-capture by imidazolium ionic liquids: tuning CO2 solubility by cation alkyl branching." Chem. Sus. Chem.. 8 (2015): 1935-1946.
Aquino, Aline S., FL Bernard, JV Borges, Luis Mafra, Felipe Dalla Vecchia, MO Vieira, R. Ligabue, VV Chaban, E. J. Cabrita, and S. Einloft. "Rationalizing the role of the anion in CO2 capture and conversion using imidazolium-based ionic liquid modified mesoporous sílica." RSC Advances. 5 (2015): 64220-64227.
Moniz, António B., and Michael Decker. "Robotics Technology Assessment: New Challenges, Implications and Risks." The Next Horizon of Technology Assessment. Prague: Technology Centre ASCR, 2015. 249-252. Abstract

Robotics technology has been applied to a wide variety of sectors and with a higher economic and social impact. In the last decades it has been one of the main elements of industrial manufacturing automation where about 1.5 million robots are currently operating, which means that 4 to 5 million workers are operating those systems. From 2014 to 2016, robot installations are estimated to increase by 6% on average per year. Besides this, in recent years the number of professional service robots has increased enormously in military and civil applications (around 130 thousand units).

Mateus, João, Miguel Domingues, and João Costa Seco Sistema de Runtime para uma Linguagem Web Reativa. INForum 2015 - Actas do 7º Simpósio de Informática. Covilhã, 2015.
Silva, João André, Tiago Vale, Ricardo Dias, Hervé Paulino, and João M. Lourenço Supporting Multiple Data Replication Models in Distributed Transactional Memory. ICDCN 2015. Goa, India: ACM, 2015. Abstract

Distributed transactional memory (DTM) presents itself as a highly expressive and programmer friendly model for con- currency control in distributed programming. Current DTM systems make use of both data distribution and replication as a way of providing scalability and fault tolerance, but both techniques have advantages and drawbacks. As such, each one is suitable for different target applications, and deployment environments. In this paper we address the support of different data replication models in DTM. To that end we propose ReDstm, a modular and non-intrusive framework for DTM, that supports multiple data replication models in a general purpose programming language (Java). We show its application in the implementation of distributed software transactional memories with different replication models, and evaluate the framework via a set of well-known benchmarks, analysing the impact of the different replication models on memory usage and transaction throughput.

Silva, João A., Tiago M. Vale, Ricardo J. Dias, Hervé Paulino, and João M. Lourenço. "Supporting Multiple Data Replication Models in Distributed Transactional Memory." Proceedings of the 2015 International Conference on Distributed Computing and Networking. ICDCN '15. Goa, India: ACM, 2015. 11:1-11:10. Abstracticdcn15-jsilva.pdf

Distributed transactional memory (DTM) presents itself as a highly expressive and programmer friendly model for concurrency control in distributed programming. Current DTM systems make use of both data distribution and replication as a way of providing scalability and fault tolerance, but both techniques have advantages and drawbacks. As such, each one is suitable for different target applications, and deployment environments. In this paper we address the support of different data replication models in DTM. To that end we propose ReDstm, a modular and non-intrusive framework for DTM, that supports multiple data replication models in a general purpose programming language (Java). We show its application in the implementation of distributed software transactional memories with different replication models, and evaluate the framework via a set of well-known benchmarks, analysing the impact of the different replication models on memory usage and transaction throughput.

Rybarczyk, Y., Seabra, J., Vernay, D., Rybarczyk, P., and Lebret M.C. "Towards an augmented assistance dog." 3rd World Conference on Information Systems and Technologies. Azores, Portugal 2015. copy.pdf
Domingues, Miguel, and João Costa Seco Type Safe Evolution of Live Systems. Workshop on Reactive and Event-based Languages & Systems (REBLS'15). Pittsburgh, 2015.rebls15.pdf
Gonçalves, L., Z. Santos, Miguel Amado, I. Craveiro, J. Cabral, Lapão L.V., A. P. Delgado, A. Correia, D. Alves, and R. Simões. "Urban Planning and Health Inequities: looking in a small-scale in a City of Cape Verde." PLOSone. 23/11/2015.DOI: 10.1371/journal.pone.0142955 (2015).
Fliedel, Christophe, Vitor Rosa, Filipa M. Alves, Ana. M. Martins, Teresa Aviles, and Samuel Dagorne. "{P,O-Phosphinophenolate zinc(II) species: synthesis, structure and use in the ring-opening polymerization (ROP) of lactide, epsilon-caprolactone and trimethylene carbonate}." {DALTON TRANSACTIONS}. {44} (2015): {12376-12387}. Abstract

{The P, O-type phosphinophenol proligands (1 center dot H, 2-PPh2-4-Me-6-Me-C6H2OH; 2 center dot H, 2-PPh2-4-Me-6-Bu-t-C6H2OH) readily react with one equiv. of ZnEt2 to afford in high yields the corresponding Zn(II)ethyl dimers of the type {[}(kappa(2)-P, O) Zn-Et](2) (3 and 4) with two mu-O-Ph bridging oxygens connecting the two Zn(II) centers, as determined by X-ray diffraction (XRD) studies in the case of 3. Based on diffusion-ordered NMR spectroscopy (DOSY), both species 3 and 4 retain their dimeric structures in solution. The alcoholysis reaction of Zn(II) alkyls 3 and 4 with BnOH led to the high yield formation of the corresponding Zn(II) benzyloxide species {[}(kappa(2)-P, O) Zn-OBn](2) (5 and 6), isolated in a pure form as colorless solids. The centrosymmetric and dimeric nature of Zn(II) alkoxides 5 and 6 in solution was deduced from DOSY NMR experiments and multinuclear NMR data. Though the heteroleptic species 5 is stable in solution, its analogue 6 is instable in CH2Cl2 solution at room temperature to slowly decompose to the corresponding homoleptic species 8 via the transient formation of (kappa(2)-P, O)(2)Zn-2(mu-OBn)(mu-kappa(1):kappa(1)-P, O) (6'). Crystallization of compound 6 led to crystals of 6', as established by XRD analysis. The reaction of ZnEt2 with two equiv. of 1 center dot H and 2 center dot H allowed access to the corresponding homoleptic species of the type {[}Zn(P, O)(2)] (7 and 8). All gathered data are consistent with compound 7 being a dinuclear species in the solid state and in solution. Data for species 8, which bears a sterically demanding P, O-ligand, are consistent with a mononuclear species in solution. The Zn(II) alkoxide species 5 and the {[}Zn(P, O)(2)]-type compounds 7 and 8 were evaluated as initiators of the ring-opening polymerization (ROP) of lactide (LA), epsilon-caprolactone (epsilon-CL) and trimethylene carbonate (TMC). Species 5 is a well-behaved ROP initiator for the homo-, co- and terpolymerization of all three monomers with the production of narrow disperse materials under living and immortal conditions. Though species 7 and 8 are ROP inactive on their own, they readily polymerize LA in the presence of a nucleophile such as BnOH to produce narrow disperse PLA, presumably via an activated-monomer ROP mechanism.}

Kauf, Thomas, Vitor Rosa, Christophe Fliedel, Roberto Pattacini, Naina Deibel, Teresa Aviles, Biprajit Sarkar, and Pierre Braunstein. "{Reactivity of TCNE and TCNQ derivatives of quinonoid zwitterions with Cu(I)}." {DALTON TRANSACTIONS}. {44} (2015): {5441-5450}. Abstract

{The reactions of TCNE- and TCNQ-functionalized (TCNE: tetracyanoethylene and TCNQ: 7,7', 8,8'-tetra-cyanoquinodimethane) zwitterionic benzoquinonemonoimines with a Cu(I)-BIAN complex (BIAN = bis-(o, o'-bisisopropylphenyl)acenaphthenequinonediimine) have been investigated and found to follow a diversity of interesting patterns. The complexes {[}Cu(BIAN)(NCMe)(L2)]BF4 (2) and {[}Cu(BIAN)(L2)(2)]BF4 (4) were obtained by reacting {[}Cu(BIAN)(NCMe) 2] BF4 (1) with one and two equivalents of L2, respectively. Following similar procedures, the complexes {[}Cu(BIAN)(NCMe)(L3)] BF4 (6) and {[}Cu(BIAN)(L3)(2)]BF4 (7) were obtained by reaction of 1 with L3. The reaction of 2 with 0.5 equiv. of 4,4'-bipyridine afforded {[}\{Cu(BIAN)-(L2)\}(2)(mu-4,4'-bipyridine)](BF4)(2) (3). The complexes were characterized by multinuclear NMR, IR and UV-Vis spectroscopic techniques, mass spectrometry, cyclic voltammetry and elemental analysis. The molecular structures of complexes 3 center dot 4CH(2)Cl(2) and 4 center dot CH2Cl2 were determined by single crystal X-ray diffraction. An unexpected coordination polymer {[}Cu(L2(-))(2)](infinity) (5) was also structurally characterized, which contains Cu(II) centres chelated by two N, O-bound ligands resulting from the monodeprotonation of L2.}

Young, M. T., S. Hua, L. Steel, D. Foffa, S. L. Brusatte, S. Thüring, O. Mateus, J. I. Ruiz-Omeñaca, P. Havlik, Y. Lepage, and M. B. De Andrade. "Addendum to ?Revision of the Late Jurassic teleosaurid genus Machimosaurus (Crocodylomorpha, Thalattosuchia)?" Royal Society Open Science. 2 (2015). Abstract
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Dias, Filipe S., Miguel N. Bugalho, Patricia M. Rodríguez-González, António Albuquerque, and Orestes J. Cerdeira. "Effects of forest certification on the ecological condition of Mediterranean streams." Journal of Applied Ecology. 52 (2015): 190-198. AbstractWebsite
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Silva, F., M. de Moura, N. Dourado, J. Xavier, F. Pereira, J. Morais, M. Dias, P. Lourenço, and F. Judas. "Fracture Characterization of Human Cortical Bone Under Mode I Loading." Journal of Biomechanical Engineering. 137 (2015): 121004. AbstractWebsite

A miniaturized version of the double cantilever beam (DCB) test is used to determine the fracture energy in human cortical bone under pure mode I loading. An equivalent crack length based data-reduction scheme is used with remarkable advantages relative to classical methods. Digital image correlation (DIC) technique is employed to determine crack opening displacement at the crack tip being correlated with the evolution of fracture energy. A method is presented to obtain the cohesive law (trapezoidal bilinear softening) mimicking the mechanical behavior observed in bone. Cohesive zone modeling (CZM) (finite-element method) was performed to validate the procedure showing excellent agreement.

Freire, D. M., M. G. Rivas, A. M. Dias, A. T. Lopes, C. Costa, T. Santos-Silva, S. Van Doorslaer, and P. J. González. "The homopentameric chlorite dismutase from Magnetospirillum sp." Journal of Inorganic Biochemistry. 151 (2015): 1-9. Abstract
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De Schutter, Amy, Hugo D. Correia, Diana M. Freire, Maria G. Rivas, Alberto Rizzi, Teresa Santos-Silva, Pablo J. Gonzalez, and Sabine Van Doorslaer. "Ligand Binding to Chlorite Dismutase from Magnetospirillum sp." Journal of Physical Chemistry B. 119 (2015): 13859-13869. Abstract
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Dias, C. J. "A method of recursive images extended to solve diffusion in multilayer materials under convective boundary conditions." International Journal of Heat and Mass Transfer. 85 (2015): 1069-1074. AbstractWebsite
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