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2014
Fliedel, Christophe, Samir Mameri, Samuel Dagorne, and Teresa Aviles. "{Controlled ring-opening polymerization of trimethylene carbonate and access to PTMC-PLA block copolymers mediated by well-defined N-heterocyclic carbene zinc alkoxides}." {APPLIED ORGANOMETALLIC CHEMISTRY}. {28} (2014): {504-511}. Abstract

{Four novel Zinc-NHC alkyl/alkoxide/chloride complexes (4, 5, 9 and 9) were readily prepared and fully characterized, including X-ray diffraction crystallography for 5 and 9. The reaction of N-methyl-N-butyl imidazolium chloride (3.HCl) with ZnEt2 (2 equiv.) afforded the corresponding {[}(CNHC)ZnCl(Et)] complex (4) via a protonolysis reaction, as deduced from NMR data. The alcoholysis of 4 with BnOH led to quantitative formation of the dinuclear Zn(II) alkoxide species {[}(CNHC)ZnCl(OBn)]2 (5), as confirmed by X-ray diffraction analysis. The NMR data are in agreement with species 5 retaining its dimeric structure in solution at room temperature. The protonolysis reaction of N-(2,6-diisopropylphenyl)-N-ethyl methyl ether imidazolium chloride (8.HCl) with ZnEt2 (2 equiv.) yielded the {[}(CNHC)ZnCl(Et)] species 9. The latter was found to be reactive with CH2Cl2 in solution and to cleanly convert to the corresponding Zn(II) dichloride {[}(CNHC)ZnCl2]2 (9), whose molecular structure was also elucidated using X-ray diffractometry. Unlike Zn(II)-NHC alkoxide species 1 and 2, which contain a NHC flanked with an additional N-functional group (i.e. thioether and ether, respectively), the Zn(II) alkoxide species 5 incorporates a monodentate NHC ligand. The Zn(II) complexes 1, 2 and 5 were tested in the ring-opening polymerization (ROP) of trimethylene carbonate (TMC). All three species are effective initiators for the controlled ROP of trimethylene carbonate, resulting in the production of narrow disperse PTMC material. Initiator 1 (incorporating a thioether moiety) was found to perform best in the ROP of TMC. Notably, the latter also readily undergoes the sequential ROP of TMC and rac-LA in the presence of a chain-transfer agent, leading to well-defined and high-molecular-weight PTMC/PLA block copolymers. Copyright (c) 2014 John Wiley & Sons, Ltd.}

Maiti, Biplab K., Teresa Aviles, Isabel Moura, Sofia R. Pauleta, and Jose J. G. Moura. "{Synthesis and characterization of {[}S2MoS2Cu(n-SPhF)](2-) (n = o, m, P) clusters: Potential F-19-NMR structural probes for Orange Protein}." {INORGANIC CHEMISTRY COMMUNICATIONS}. {45} (2014): {97-100}. Abstract

{Three fluorinated Mo-Cu-thiolate isomers,{[}Ph4Ph{[}S2MoS2Cu(n-SPhF)], {[}n-SPhF = 2-fluorothiophenol (la)], 3-fluorothiophenol (lb), and 4-fluorothiophenol (1c)] were synthesized and spectroscopically characterized. The F-19-NMR signal of the fluorine atom in the.benzene has different chemical shift for each isomer, which is highly influenced by the local environment that can be manipulated by different solvents and solutes. The fluorine-19 chemical shift is an advantageous NMR structural probe in alternative to H-1-NMR {[}B.K. Maiti, T. Aviles, M. Matzapetakis, I. Moura, S.R. Pauleta, JJ.G. Moura, Eur. J. Inorg. Chem. (2012) 4159.], that can be used to provide local information on the pocket of the metal cluster in the Orange Protein (ORP). (C) 2014 Elsevier B.V. All rights reserved.}

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 O-2/HO-}." {INORGANIC CHEMISTRY}. {53} (2014): {12799-12808}. Abstract

{The complex {[}Ph4P](2){[}Cu(bdt)(2)] (1(red)) was synthesized by the reaction of {[}Ph4P]2{[}S2MoS2CuCl] with H2bdt (bdt = benzene-1,2-dithiolate) in basic medium. 1(red) is highly susceptible toward dioxygen, affording the one electron oxidized diamagnetic compound {[}Ph4P]{[}Cu(bdt)(2)] (1(ox)). The interconversion between these two oxidation states can be switched by addition of O-2 or base (Et4NOH = tetraethylammonium hydroxide), as demonstrated by cyclic voltammetry and UV-visible and EPR spectroscopies. Thiomolybdates, in free or complex forms with copper ions, play an important role in the stability of 1(red) during its synthesis, since in its absence, 1(ox) is isolated. Both 1(red) and 1(ox) were structurally characterized by X-ray crystallography. EPR experiments showed that 1(red) is a Cu(II)-sulfur complex and revealed strong covalency on the copper-sulfur bonds. DFT calculations confirmed the spin density delocalization over the four sulfur atoms (76%) and copper (24%) atom, suggesting that 1(red) has a ``thiyl radical character{''}. Time dependent DFT calculations identified such ligand to ligand charge transfer transitions. Accordingly, 1(red) is better described by the two isoelectronic structures {[}Cu(I)(bdt(2), 4S(3-{*}))](2-) {[}Cu-II(bdt(2), 4S(4-))](2-). On thermodynamic grounds, oxidation of 1(red) (doublet state) leads to 1(ox) singlet state, {[}Cu-III(bd(t)2, 4S(4-))](1-).}

Barišić, Ankica, Vasco Amaral, Miguel Goulão, and Ademar Aguiar. "Introducing usability concerns early in the DSL development cycle: FlowSL experience report." Model-Driven Development Processes and Practices Workshop Proceedings, MD2P2 2014. Valencia, Spain 2014. Abstractflowslmodelsdraft.pdf

Domain-Specific Languages (DSLs) developers aim to narrow the gap between the level of abstraction used by domain users and the one provided by the DSL, in order to help taming the increased complexity of computer systems and real-world problems. The quality in use of a DSL is essential for its successful adoption. We illustrate how a usability evaluation process can be weaved into the development process of a concrete DSL - FlowSL - used for specifying humanitarian campaign processes lead by an international Non-Governmental Organization. FlowSL is being developed following an agile process using Model-Driven Development (MDD) tools, to cope with vague and poorly understood requirements in the beginning of the development process.

Santos, Jose Paulo, Maria Conceição Martins, Ana Maria Costa, José Pires Marques, Paul Indelicato, and Fernando Parente. "Theoretical determination of K X-ray transition energy and probability values for highly charged ions of lanthanum and cerium." The European Physical Journal D. 68 (2014): 244. AbstractWebsite
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Santos, Jose Paulo, Maria Conceição Martins, Ana Maria Costa, José Pires Marques, Paul Indelicato, and Fernando Parente. "Theoretical determination of K X-ray transition energy and probability values for highly charged ions of lanthanum and cerium." The European Physical Journal D. 68 (2014): 244. AbstractWebsite
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Habibullin, Maksim, Vladimir Pikalov, Viktor Mescheryakov, and Stanimir Valtchev. "Active power filter with common {DC} link for compensation of harmonic distortion in power grids." 2014 16th International Power Electronics and Motion Control Conference and Exposition. Institute of Electrical {&} Electronics Engineers ({IEEE}), 2014. Abstract
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Guimarães, D., J. P. Santos, M. L. Carvalho, M. S. Diniz, B. House, and V. M. Miller. "Analytical evidence of heterogeneous lead accumulation in the hypothalamic defence area and nucleus tractus solitarius." NeuroToxicology. 44 (2014): 91-97. AbstractWebsite

Lead is a potent toxicant associated with adverse cardiovascular effects and hypertension in children. Yet, few studies have determined if autonomic dysfunction associated with lead exposure involves brain regions which regulate autonomic responses. Central autonomic nuclei such as the nucleus tractus solitarius (NTS) and hypothalamic defence area (HDA) may be particularly sensitive to lead infiltration because they are adjacent to ventricles and areas with semi-permeable blood-brain-barriers. To understand if autonomic nuclei are sensitive to lead accumulation Wistar rats were exposed to lead from the gestational period and lead levels were quantified in brain regions that regulate arterial pressure: the NTS and the HDA. Energy dispersive X-ray fluorescence (EDXRF) was used to quantify total brain lead levels and revealed no differences between exposed and control tissues; measured values were close to the detection limit (2μg/g). Electrothermal atomic absorption spectrometry (ETAAS) was also used, which has a greater sensitivity, to quantify lead. There was ∼2.1μg/g lead in the NTS and ∼3.1μg/g lead in the HDA of exposed rats, and no lead in the control rats. There were greater lead levels in the HDA (∼50%) as compared with the NTS. Pathology studies revealed more prominent lead granules in the HDA as compared with the NTS. Increased microglia and astrocyte activation was also noted in the NTS of lead exposed rats as compared with the HDA. Regional differences in neuro-inflammatory responses likely contribute to heterogeneous lead accumulation, with enhanced clearance of lead in the NTS. Future studies will resolve the mechanisms underpinning tissue-specific lead accumulation.

Guimarães, D., J. P. Santos, M. L. Carvalho, M. S. Diniz, B. House, and V. M. Miller. "Analytical evidence of heterogeneous lead accumulation in the hypothalamic defence area and nucleus tractus solitarius." NeuroToxicology. 44 (2014): 91-97. AbstractWebsite

Lead is a potent toxicant associated with adverse cardiovascular effects and hypertension in children. Yet, few studies have determined if autonomic dysfunction associated with lead exposure involves brain regions which regulate autonomic responses. Central autonomic nuclei such as the nucleus tractus solitarius (NTS) and hypothalamic defence area (HDA) may be particularly sensitive to lead infiltration because they are adjacent to ventricles and areas with semi-permeable blood-brain-barriers. To understand if autonomic nuclei are sensitive to lead accumulation Wistar rats were exposed to lead from the gestational period and lead levels were quantified in brain regions that regulate arterial pressure: the NTS and the HDA. Energy dispersive X-ray fluorescence (EDXRF) was used to quantify total brain lead levels and revealed no differences between exposed and control tissues; measured values were close to the detection limit (2μg/g). Electrothermal atomic absorption spectrometry (ETAAS) was also used, which has a greater sensitivity, to quantify lead. There was ∼2.1μg/g lead in the NTS and ∼3.1μg/g lead in the HDA of exposed rats, and no lead in the control rats. There were greater lead levels in the HDA (∼50%) as compared with the NTS. Pathology studies revealed more prominent lead granules in the HDA as compared with the NTS. Increased microglia and astrocyte activation was also noted in the NTS of lead exposed rats as compared with the HDA. Regional differences in neuro-inflammatory responses likely contribute to heterogeneous lead accumulation, with enhanced clearance of lead in the NTS. Future studies will resolve the mechanisms underpinning tissue-specific lead accumulation.

Valtchev, Stanimir, Joana Almeida, Jorge P. Teixeira, and Ben J. Klaassens. "Conversion of wind-induced vibrations into electricity." 2014 {IEEE} 36th International Telecommunications Energy Conference ({INTELEC}). Institute of Electrical {&} Electronics Engineers ({IEEE}), 2014. Abstract
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Mihaylov, Kaloyan, Rumen Arnaudov, and Stanimir Valtchev. "Energy harvesting from the voltage drop in {TN}-S, {TN}-C-S and other consumer electric networks." 2014 16th International Power Electronics and Motion Control Conference and Exposition. Institute of Electrical {&} Electronics Engineers ({IEEE}), 2014. Abstract
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Merino, E. G., G. Lavareda, P. Brogueira, A. Amaral, C. Nunes de Carvalho, and PL Almeida. "InOx thin films deposited by plasma assisted evaporation: Application in light shutters." VACUUM. 107 (2014): 116-119. Abstract

An integration of undoped InOx and commercial ITO thin films into laboratory assembled light shutter devices is made. Accordingly, undoped transparent conductive InOx thin films, about 100 nm thick, are deposited by radiofrequency plasma enhanced reactive thermal evaporation (rf-PERTE) of indium teardrops with no intentional heating of the glass substrates. The process of deposition occurs at very low deposition rates (0.1–0.3 nm/s) to establish an optimized reaction between the oxygen plasma and the metal vapor. These films show the following main characteristics: transparency of 87% (wavelength, λ = 632.8 nm) and sheet resistance of 52 Ω/sq; while on commercial ITO films the transparency was of 92% and sheet resistance of 83 Ω/sq. The InOx thin film surface characterized by AFM shows a uniform grain texture with a root mean square surface roughness of Rq∼2.276 nm. In contrast, commercial ITO topography is characterized by two regions: one smoother with Rq∼0.973 nm and one with big grains (Rq∼3.617 nm). For the shutters assembled using commercial ITO, the light transmission coefficient (Tr) reaches the highest value (Trmax) of 89% and the lowest (Trmin) of 1.3% [13], while for the InOx shutters these values are 80.1% and 3.2%, respectively. Regarding the electric field required to achieve 90% of the maximum transmission in the ON state (Eon), the one presented by the devices assembled with commercial ITO coated glasses is 2.41 V/μm while the one presented by the devices assembled with InOx coated glasses is smaller, 1.77 V/μm. These results corroborate the device quality that depends on the base materials and fabrication process used.

Merino, E. G., G. Lavareda, P. Brogueira, A. Amaral, C. Nunes de Carvalho, and PL Almeida. "InOx thin films deposited by plasma assisted evaporation: Application in light shutters." VACUUM. 107 (2014): 116-119. Abstract

{An integration of undoped InOx and commercial ITO thin films into laboratory assembled light shutter devices is made. Accordingly, undoped transparent conductive InOx thin films, about 100 nm thick, are deposited by radiofrequency plasma enhanced reactive thermal evaporation (rf-PERTE) of indium teardrops with no intentional heating of the glass substrates. The process of deposition occurs at very low deposition rates (0.1-0.3 nm/s) to establish an optimized reaction between the oxygen plasma and the metal vapor. These films show the following main characteristics: transparency of 87% (wavelength

Silva, João A., João M. Lourenço, and Hervé Paulino. "Um Mecanismo de Caching para o Protocolo {SCORe}." Proceedings of INForum Simpósio de Informática. INForum 2014. Porto, Portugal: FEUP Edições, 2014. 260-275. Abstractinforum14-jsilva.pdf

Os protocolos de replicação parcial de dados apresentam um grande potencial de escalabilidade. O SCORe é um protocolo para replicação parcial proposto recentemente que faz uso de controlo de concorrência multi-versão. Neste artigo abordamos um dos problemas principais que afeta o desempenho deste tipo de protocolos: a localidade dos dados, i.e., pode-se dar o caso do nó local não ter uma cópia dos dados a que pretende aceder, e nesse caso é necessário realizar uma ou mais operações de leitura remota. Assim, a não ser que se empreguem técnicas para melhorar a localidade no acesso aos dados, o número de operações de leitura remota aumenta com o tamanho do sistema, acabando por afetar o desempenho do mesmo. Nesse sentido, introduzimos um mecanismo de caching que permite replicar cópias de dados remotos de maneira a que seja poss{\'ı}vel servir localmente dados remotos enquanto que se mantém a consistência dos mesmos e a escalabilidade oferecida pelo protocolo. Avaliamos o mecanismo de caching com um benchmark conhecido da literatura e os resultados experimentais mostram resultados animadores com algum aumento no desempenho do sistema e uma redução considerável da quantidade de operações de leitura remota.

Valtchev, Stanimir, Rui Neves-Medeiros, Anastassia Krusteva, George Gigov, and Plamen Avramov. "A wireless energy transceiver based on induction heating equipment." 2014 16th International Power Electronics and Motion Control Conference and Exposition. Institute of Electrical {&} Electronics Engineers ({IEEE}), 2014. Abstract
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Marzola, M., O. Mateus, J. Russo, and J. Milàn. "Comparison of modern and fossil Crocodylomorpha eggs and contribution to the oophylogeny of Amniota." XII Annual Meeting of the European Association of Vertebrate Palaeontologists. Regione Piemonte: European Association of Vertebrate Palaeontologists. Museo Regionale di Scienze Naturali, 2014. marzola_et_al._2014_comparison_of_modern_and_fossil_crocodylomorpha_eggs_and_contribution_to_the_oophylogeny_of_amniota-_eavp_2014.pdf
Saponaro, A., S. R. Pauleta, F. Cantini, M. Matzapetakis, C. Hammann, C. Donadoni, L. Hu, G. Thiel, L. Banci, B. Santoro, and A. Moroni. "Structural basis for the mutual antagonism of cAMP and TRIP8b in regulating HCN channel function." Proc Natl Acad Sci U S A. 111 (2014): 14577-82. AbstractWebsite

cAMP signaling in the brain mediates several higher order neural processes. Hyperpolarization-activated cyclic nucleotide-gated (HCN) channels directly bind cAMP through their cytoplasmic cyclic nucleotide binding domain (CNBD), thus playing a unique role in brain function. Neuronal HCN channels are also regulated by tetratricopeptide repeat-containing Rab8b interacting protein (TRIP8b), an auxiliary subunit that antagonizes the effects of cAMP by interacting with the channel CNBD. To unravel the molecular mechanisms underlying the dual regulation of HCN channel activity by cAMP/TRIP8b, we determined the NMR solution structure of the HCN2 channel CNBD in the cAMP-free form and mapped on it the TRIP8b interaction site. We reconstruct here the full conformational changes induced by cAMP binding to the HCN channel CNBD. Our results show that TRIP8b does not compete with cAMP for the same binding region; rather, it exerts its inhibitory action through an allosteric mechanism, preventing the cAMP-induced conformational changes in the HCN channel CNBD.

Branquinho, Rita, Daniela Salgueiro, Lídia Santos, Pedro Barquinha, Luis Pereira, Rodrigo Ferrão De Paiva Martins, and Elvira Fortunato. "{Aqueous Combustion Synthesis of Aluminum Oxide Thin Films and Application as Gate Dielectric in GZTO Solution-based TFTs.}." ACS applied materials {&} interfaces. 6 (2014): 195592-9. AbstractWebsite

Solution processing has been recently considered as an option when trying to reduce the costs associated to deposition under vacuum. In this context most of the research efforts have been centered in the development of the semiconductors processes nevertheless the development of the most suitable dielectrics for oxide based transistors is as relevant as the semiconductor layer itself. In this work we explore the solution combustion synthesis and report on a completely new and green route for the preparation of amorphous aluminum oxide thin films; introducing water as solvent. Optimized dielectric layers were obtained for a water based precursor solution with 0.1 M concentration and demonstrated high capacitance, 625 nF cm-2 at 10 kHz, and a permittivity of 7.1. These thin films were successfully applied as gate dielectric in solution processed gallium-zinc-tin oxide (GZTO) thin film transistors (TFTs) yielding good electrical performance such as subthreshold slope of about 0.3 V dec-1 and mobility above 1.3 cm2 V-1 s-1.

Branquinho, Rita, Daniela Salgueiro, Lidia Santos, Pedro Barquinha, Luis Pereira, Rodrigo Martins, and Elvira Fortunato. "Aqueous Combustion Synthesis of Aluminum Oxide Thin Films and Application as Gate Dielectric in GZTO Solution-Based TFTs." Acs Applied Materials & Interfaces. 6 (2014): 19592-19599. AbstractWebsite
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Katriel, Jacob, J. P. Marques, P. Indelicato, A. M. Costa, M. C. Martins, J. P. Santos, and F. Parente. "Approach towards the critical charge of some excited states of the Be isoelectronic series." Physical Review A. 90 (2014): 052519-5. AbstractWebsite
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Valletta, A., G. Fortunato, L. Mariucci, P. Barquinha, R. Martins, and E. Fortunato. "Contact Effects in Amorphous InGaZnO Thin Film Transistors." Journal of Display Technology. 10 (2014): 956-961. AbstractWebsite
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Branquinho, Rita, Daniela Salgueiro, L??dia Lídia Santos, Pedro Barquinha, Luís Lu??s Pereira, Rodrigo Martins, and Elvira Fortunato. "{Aqueous combustion synthesis of aluminum oxide thin films and application as gate dielectric in GZTO solution-based TFTs}." ACS Applied Materials and Interfaces. 6 (2014): 19592-19599. AbstractWebsite

Solution processing has been recently considered as an option when trying to reduce the costs associated with deposition under vacuum. In this context, most of the research efforts have been centered in the development of the semiconductors processes nevertheless the development of the most suitable dielectrics for oxide based transistors is as relevant as the semiconductor layer itself. In this work we explore the solution combustion synthesis and report on a completely new and green route for the preparation of amorphous aluminum oxide thin films; introducing water as solvent. Optimized dielectric layers were obtained for a water based precursor solution with 0.1 M concentration and demonstrated high capacitance, 625 nF cm(-2) at 10 kHz, and a permittivity of 7.1. These thin films were successfully applied as gate dielectric in solution processed gallium-zinc-tin oxide (GZTO) thin film transistors (TFTs) yielding good electrical performance such as subthreshold slope of about 0.3 V dec(-1) and mobility above 1.3 cm(2) V(-1) s(-1).

Santos, I., M. S. Diniz, M. L. Carvalho, and J. P. Santos. "Assessment of Essential Elements and Heavy Metals Content on Mytilus galloprovincialis from River Tagus Estuary." Biological Trace Element Research (2014). AbstractWebsite

Trace elemental content was analysed in edible tissues of Mytilus galloprovincialis collected in five different sampling areas near the mouth of river Tagus estuary in Lisbon. The concentrations of essential elements (S, K, Ca, Fe, Cu, Zn, As, Br and Sr) were determined by energy-dispersive X-ray fluorescence (EDXRF) spectrometry, while toxic elements (Cr, Cd, Hg, Se and Pb) were measured by inductively coupled plasma-atomic emission spectrometry (ICP-AES). The results show that the essential elements K and S are present at the highest concentrations in all the studied samples reaching 2,920 and 4,520 μg g(-1) (fresh weight), respectively. The highest levels of heavy metals found were in two areas close to the city for Pb and Cd, but below the maximum allowed values.

Rahangdale, H. V., M. Guerra, P. K. Das, S. De, J. P. Santos, D. Mitra, and S. Saha. "Determination of subshell-resolved <span class="aps-inline-formula"><math><mi>L</mi></math></span>-shell-ionization cross sections of gold induced by 15–40-keV electrons." Physical Review A. 89 (2014): 052708. AbstractWebsite
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Amaro, P., C. I. Szabo, S. Schlesser, A. Gumberidze, E. G. Kessler, A. Henins, E. O. Le Bigot, M. Trassinelli, J. M. Isac, P. Travers, M. Guerra, J. P. Santos, and P. Indelicato. "A vacuum double-crystal spectrometer for reference-free X-ray spectroscopy of highly charged ions." Radiation Physics and Chemistry. 98 (2014): 132-149. AbstractWebsite

Radiation Physics and Chemistry, 98 + (2014) 132-149. doi:10.1016/j.radphyschem.2014.01.015