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This article, in its central part, tries to expose more or less succinctly the importance of the concept of Sumak kausay in the Ecuadorian Constitution and the National Plan for Good Living 2013-2017, showing continuities and differences that obey a and others, the different political moments in which these two documents have been produced: the Constitution, in 2008 at the beginning of the citizen revolution and the Plan of Good Living/Living Well, following the re-election of Rafael Correa for a new presidential term in 2013. During a brief introduction realizes the Ecuadorian historical context background, allowing the emergence of Sumak Kawsay and conclusions some echoes of the political debate over attempts are both Ecuador and Bolivia producing collected government spending Speech Good Living/Living Well programs and projects of real politics.

6 pages, 4 figures.-- PACS: 64.70.Dv; 68.55.-a; 81.05.Cy; 61.43.Dq; 81.05.Gc; 78.66.Jg; 78.66.Db; 42.62.-b ; The dynamics of melting-rapid solidification of amorphous Ge films on transparent substrates upon irradiation with nanosecond laser pulses has been analyzed by means of real time reflectivity measurements performed both at the air-film and film-substrate interfaces. The effect of the heat flow conditions on the rapid solidification process has been studied by comparing the behavior of films with thicknesses ranging from 50 to 180 nm on substrates with different thermal conductivities like glass, quartz, and sapphire. The films deposited onto substrates of low thermal conductivity (glass and quartz) undergo a local delayed melting process in the vicinity of the film-substrate interface, the process being dependent on the film thickness and/or the laser fluence. This delayed melting process is never observed in films deposited on sapphire. The comparison of the results suggests that the solidification heat released from the primary melt is responsible for the delayed melting process at the film-substrate interface whenever the heat-transfer ratio to the substrate is low enough. ; The Marie Curie TMR program for the European Union (ERB40001GT54352) is acknowledged for financial support. ; Peer reviewed

This work describes the phase transitions occurring at the film-substrate interface of amorphous germanium films upon nanosecond laser-pulse-induced melting of the surface. Films with thickness ranging from 50 to 130 nm deposited on glass substrates were studied. Real-time reflectivity measurements with subnanosecond time resolution performed both at the air-film and film-substrate interfaces were used to obtain both surface and in-depth information of the process. In the thicker films (≥80 nm), the enthalpy released upon solidification of a shallow molten surface layer induces a thin buried liquid layer that self-propagates in-depth towards the film-substrate interface. This buried liquid layer propagates with a threshold velocity of 16±1 ms and causes, eventually, melting at the film-substrate interface. In the thinnest film (50 nm) there is no evidence of the formation of the buried layer. The presence of the self-propagating buried layer for films thicker than 80 nm at low and intermediate laser fluences is discussed in terms of the thermal gradient in the primary melt front and the heat released upon solidification. © 2005 American Institute of Physics. ; This work has been partially supported by the MCYT through Project No. DPI: DPI2002-00151 and by the European Union in the framework of the TMR ERB FMRX Contract No. CT098-0188 "Laser Cleaning" Network. N. C. acknowledges the funding of the European Union through the latter contract. ; Peer Reviewed

Rapid solidification dynamics in amorphous germanium films melted by nanosecond laser pulses was analyzed. Single-shot subnanosecond time resolved reflectivity measurements were carried out. Results showed that once a minimum depth was induced, a bulk solidification process followed by the release of solidification enthalpy was found. ; This work has been partially supported by the European Union in the framework of the TMR ERB FMRX CT098- 0188 ''Laser Cleaning'' Network. N.C. acknowledges the funding of the European Union through the same contract. ; Peer Reviewed

3 pages, 3 figures. ; We report on the mechanisms responsible for the formation of optical waveguides upon femtosecond laser irradiation of an alkaline lead-oxide silicate glass. MicroRaman spectroscopy and nonlinear fluorescence were employed to probe the local glass network structure and the formation of optically active defects respectively. At low laser pulse energies, the laser modified region is formed by a single light guiding region, whereas for pulses above 14 µJ the modified region is formed by a central dark zone, which does not guide light, accompanied by light guiding zones located in the surrounding of the dark one. This behavior is different from that observed in common silica glass systems but agrees with recent results obtained in phosphate and heavy metal oxide glasses. However, our results show that, unlike the latter glass, local densification of the glass occurs in the whole laser modified region, i.e., in the dark and the guiding zones. The suppression of light guiding in the dark region is explained by a high density of absorbing color centers. ; This work was partially supported by CICYT (Spain) under Project No. DPI2002-00151. One of the authors (V.D.B.) acknowledges the financial support of the CSIC and the European Social Fund through an I3P Ph.D. fellowship. Another author (P.L.-A. acknowledges funding from the Spanish Government ( the Ramón y Cajal program and Grant No. TIC2003-07485). ; Peer reviewed