Let G be a square complex matrix with less than k nonconstant invariant factors. We find a complex matrix that gives an optimal approximation to G among all possible matrices that have more than or equal to k invariant ...

El cemento y sus derivados, como los morteros o el hormigón, son generalmente considerados materiales de bajo nivel tecnológico. A pesar de ser el material manufacturado más empleado en el mundo, otros como los plásticos, ...

This paper deals with the economics of gasification facilities in general and IGCC power plants in particular. Regarding the prospects of these systems, passing the technological test is one thing, passing the economic ...

Background: The diagnosis of invasive candidiasis is difficult because there are no specific clinical manifestations of the disease and colonization and infection are difficult to distinguish. In the last decade, much ...

Background: Different studies show evidence that several unicellular organisms display a cellular metabolic structure characterized by a set of enzymes which are always in an active state (metabolic core), while the rest ...

Background: Estimation of the frequency of latent tuberculosis infection (LTBI) is difficult in areas with low tuberculosis infection rates and high exposure to non-tuberculous mycobacteria (NTM), including BCG vaccination. ...

Invasive candidiasis is a frequent and often fatal complication in immunocompromised and critically ill patients. Unfortunately, the diagnosis of invasive candidiasis remains difficult due to the lack of specific clinical ...

We show some examples of compact symplectic solvmanifolds, of dimension greater than four, which are cohomologically Kähler and do not admit Kähler metric since their fundamental groups cannot be the fundamental group ...

[EN]The practical context of this thesis work is natural interaction in Interactive Multimedia Tabletops using visually recognized hand gestures. An interaction language has been de ned for the speci c characteristics ...

[EN] Over the last decade or so, many writers have argued that inclusive practices are more likely to be developed when school communities are involved in collaborative processes of inquiry, reflection and action in order ...