Amaro, P, Fratini F, Fritzsche S, Indelicato P, Santos JP, Surzhykov A.
2012.
Parametrization of the angular correlation and degree of linear polarization in two-photon decays of hydrogenlike ions, Oct. Physical Review A. 86:042509.
AbstractThe spontaneous two-photon emission in hydrogenlike ions is investigated within the framework of second- order perturbation theory and Dirac’s equation. Special attention is paid to the angular correlation of the emitted photons as well as to the degree of linear polarization of one of the two photons, if the second is just observed under arbitrary angles. Expressions for the angular correlation and the degree of linear polarization are expanded in powers of cosine functions of the two-photon opening angle, whose coefficients depend on the atomic number and the energy sharing of the emitted photons. The effects of including higher (electric and magnetic) multipoles upon the emitted photon pairs beyond the electric-dipole approximation are also discussed. Calculations of the coefficients are performed for the transitions 2s1/2 → 1s1/2, 3d3/2 → 1s1/2, and 3d5/2 → 1s1/2, along the entire hydrogen isoelectronic sequence (1
Barbosa, J, Barbosa DJ, Capela JP, Oliveira JMA, Silva R, Ferreira LM, Siopa F, Branco PS, Fernandes E, Duarte JA, de Lourdes Bastos M, Carvalho F, Carvalho D.
2012.
Pro-oxidant effects of Ecstasy and its metabolites in mouse brain synaptosomes, FEB. BRITISH JOURNAL OF PHARMACOLOGY. 165:1017-1033., Number 4B
Abstractn/a
Amado, M, Lopes T.
2012.
Pré-Fabricação Aplicada ao Contexto de Reabilitação de EdifíciosS, 26 April. CCRSEEL. , Lisbon: Faculdade de Ciências e Tecnologia
AbstractO sector da construção enfrenta actualmente um momento de crise na sua produção. Esta situação tem levado as empresas nacionais a apostar mais no mercado da reabilitação de edifícios. A acrescentar a esta mudança de mercado alvo, o ambiente conturbado que envolve as empresas de construção tem também estimulado, pelo menos as mais competitivas, a implementarem acções que conduzam à melhoria contínua da sua produtividade.
A industrialização do sector, através da utilização da pré-fabricação, mostra-se como uma possível solução para atingir esta melhoria desejada, considerando as significativas vantagens que a aplicação deste tipo de soluções introduz numa obra.
Existem contudo, ainda algumas barreiras no sector da construção que levam a uma reduzida utilização de
soluções de pré-fabricação, sendo a falta de conhecimento dos intervenientes das variedades de tecnologias existentes no mercado e em desenvolvimento, o principal obstáculo à sua adopção.
O presente artigo pretende, tornar evidentes as vantagens que esta tecnologia construtiva traz para o processo de construção e reabilitação, tanto ao nível de eficiência económica como ao nível dos seus benefícios ambientais e sociais, bem como, evidenciar as possibilidades de aplicação de sistemas de pré-fabricação existentes e em desenvolvimento, em detrimento das tecnologias construtivas convencionais, para diversas acções de
reabilitação habitualmente realizadas num edifício.
Dantas, JM, Morgado L, Londer YY, Fernandes AP, Louro RO, Pokkuluri PR, Schiffer M, Salgueiro CA.
2012.
Pivotal role of the strictly conserved aromatic residue F15 in the cytochrome c7 family. Journal of Biological Inorganic Chemistry. 17(1):11-24.
AbstractCytochromes c7 are periplasmic triheme proteins that have been reported exclusively in δ-proteobacteria. The structures of five triheme cytochromes identified in Geobacter sulfurreducens and one in Desulfuromonas acetoxidans have been determined. In addition to the hemes and axial histidines, a single aromatic residue is conserved in all these proteins - phenylalanine 15 (F15). PpcA is a member of the G. sulfurreducens cytochrome c7 family that performs electron/proton energy transduction in addition to electron transfer that leads to the reduction of extracellular electron acceptors. For the first time we probed the role of the F15 residue in the PpcA functional mechanism, by replacing this residue with the aliphatic leucine by site-directed mutagenesis. The analysis of NMR spectra of both oxidized and reduced forms showed that the heme core and the overall fold of the mutated protein were not affected. However, the analysis of 1H-15N heteronuclear single quantum coherence NMR spectra evidenced local rearrangements in the α-helix placed between hemes I and III that lead to structural readjustments in the orientation of heme axial ligands. The detailed thermodynamic characterization of F15L mutant revealed that the reduction potentials are more negative and the redox-Bohr effect is decreased. The redox potential of heme III is most affected. It is of interest that the mutation in F15, located between hemes I and III in PpcA, changes the characteristics of the two hemes differently. Altogether, these modifications disrupt the balance of the global network of cooperativities, preventing the F15L mutant protein from performing a concerted electron/proton transfer.
Batalha, IL, Lowe CR, Roque ACA.
2012.
Platforms for enrichment of phosphorylated proteins and peptides in proteomics. Trends in Biotechnology. 30(2):100-110.
AbstractProtein phosphorylation is a complex and highly dynamic process involved in numerous biological events. Abnormal phosphorylation is one of the underlying mechanisms for the development of cancer and metabolic disorders. The identification and absolute quantification of specific phospho-signatures can help elucidate protein functions in signaling pathways and facilitate the development of new and personalized diagnostic and therapeutic tools. This review presents a variety of strategies currently utilized for the enrichment of phosphorylated proteins and peptides before mass spectrometry analysis during proteomic studies. The investigation of specific affinity reagents, allied to the integration of different enrichment processes, is triggering the development of more selective, rapid and cost-effective high-throughput automated platforms.