Os serviços Web são frequentemente suportados por sistemas com uma arquitetura em camadas, sendo utilizadas bases de dados relacionais para armazenamento dos dados. A replicação dos diversos componentes tem sido uma das formas utilizadas para obter melhorarias de escalabilidade destes serviços. Adicionalmente, a utilização de bases de dados em memória permite alcançar um desempenho mais elevado. No entanto é conhecida a fraca escalabilidade das bases de dados com o número de núcleos em máquinas multi-núcleo. Neste artigo propomos uma nova abordagem para lidar com este problema, intitulada MacroDDB. Utilizando uma solução de replicação hierárquica, a nossa proposta, replica a base da dados em vários nós, sendo que cada nó, por sua vez, executa um conjunto de réplicas da base de dados. Esta abordagem permite assim lidar com a falta de escalabilidade das bases de dados relacionais em máquinas multi-núcleo, o que por sua vez melhora a escalabilidade geral dos serviços.

Lipid-modified azurin (Laz) from Neisseria gonorrhoeae is a type 1 copper protein proposed to be the electron donor to several enzymes involved in the resistance mechanism to reactive oxygen and nitrogen species. Here we report the backbone and side-chain resonance assignment of Laz in the reduced form, which has been complete at 97 %. The predicted secondary structure indicates that this protein belongs to the azurin subfamily of type 1 copper proteins.

In order to gain insights into the interplay between Cu(I) and Cu(II) in sulfur-rich protein environments, the first preparation and characterization of copper-substituted forms of the wild-type rubredoxin (Rd) from Desulfovibrio vulgaris Hildenborough are reported, as well as those of its variant C42A-Rd. The initial products appear to be tetrahedral Cu(I)(S-Cys)n species for the wild type (n=4) and the variant C42A (n=3, with an additional unidentified ligand). These species are unstable to aerial oxidation to products, whose properties are consistent with square planar Cu(II)(S-Cys)n species. These Cu(II) intermediates are susceptible to auto-reduction by ligand S-Cys to produce stable Cu(I) final products. The original Cu(I) center in the wild-type system can be regenerated by reduction, suggesting that the active site can accommodate Cu(I)(S-Cys)2 and Cys-S-S-Cys fragments in the final product. The absence of one S-Cys ligand prevents similar regeneration in the C42A-Rd system. These results emphasize the redox instability of Cu(II)-(S-Cys)n centers.

The development of web applications that manipulate geo-referenced information is often supported by Application Programming Interfaces (APIs), allowing a fast development cycle for high quality applications. APIs can be used by programmers with different expertise levels and choosing an adequate API may
have a dramatic impact on the productivity achieved by those programmers. Our goal is to compare maps APIs with respect to their usability. We compare three different APIs: the Google Maps JavaScript API, the ArcGIS API for JavaScript, and the OpenLayers JavaScript Mapping Library. Our comparison is supported by
a set of software metrics and is performed in two orthogonal ways: the comparison of three implementations of the same system prototype, each using one of the APIs under scrutiny; the comparison of the APIs specifications. The main results of the study are related to the size of the APIs, with the Google API being significantly smaller than the others.

In this work, we obtained a charge state distribution inside an Ar plasma produced by an electron–cyclotron-resonance ion source. The processes that lead to the observed lines in x-ray spectra are identified and included in the simulated x-ray spectrum. The geometrical constraints of the flat double crystal spectrometer, used to measure the x-ray spectrum, are investigated as they are crucial for correctly obtaining the ion densities from the observed transition amplitudes. Multiple electron impact ionization is included, and a realistic electron velocity distribution is taken into account. The charge state distribution of the Ar ions is compared to measured extracted ionic currents.

This work refers to experimental and 3D nonlinear FEA on punching. Numerical results were compared with experimental ones in order to benchmark the FE model and afterwards a parametric study was conducted, changing the reinforcement ratio, slab thickness, concrete strength and column dimensions, running a total of 360 models, where their effect on punching capacity is shown. EC2 and MC2010 provisions agreed approximately with experimental and FEA results. Based in the FEA results it is proposed an equation to predict the punching capacity with the introduction of fracture mechanics parameter, which was compared with several experimental results, giving good approximation.

The sand pile model, in conjunction with Bean model, is often applied to describe single grain bulk superconductors. However, in several applications such as electric motors, multiseeded bulks are needed, due to the need to increase sample dimensions. In this paper, an extension of the sand pile model is presented in order to manage this type of materials. Multiseeded HTS bulk superconductors, produced, e.g., by the top-seeded melt growth process, are characterized by intra- and intergrain currents, and these are reflected in the model. However, identifying these currents from flux density measurements is not straightforward, when considering more than one grain. In fact, the number of currents increases with the number of grains, and these have to be identified from the measured field surface. A method to identify these currents based on genetic algorithms is validated with artificial data and then used in real measurements.