Spain:countries of the world

Spain has been the home of some of the world's great artists and has museums and galleries to match. In the cities, narrow twisting old streets suddenly open up to views of the daring modern architecture, as a culture of old and new mix and mingle in the city's nightlife. There are endless tracts of wild and crinkled sierra to explore, as well as some spectacularly rugged stretches of coast. Culturally, the country is littered with superb old buildings, from Roman aqueducts to Gothic cathedrals, and almost every second village has a medieval castle. With more than 115 years exploring the globe with its writers, photographers, and research expeditions, "National Geographic" is uniquely positioned to introduce your readers to everything they need to know about the countries of the world.

Creating gusto through games and goals

Goal-based learning (GBL) has long been used for teaching (Schank and Kass, 1996) and training (Collins, 1994), and game playing is also very widely used (Fudenberg and Levine, 1998). When both are used together it can become a winning combination that focuses students? attention, dismisses precepts about a subject, lowers barriers to preferred learning-styles and open minds to new tools, ideas and concepts. The combination can be achieved using basic traditional physical props (e.g. pens and paper) or advanced internet technology. This report briefly describes an offline and online approach and then summarises some of the main benefits to be gained from combining games and goals to get students going in the right pedagogical direction.

A model for the modular evolution of rna addressing open questions on the origin of life

A main unsolved problem in the RNA world scenario for the origin of life is how a template-dependent RNA polymerase ribozyme emerged from short RNA oligomers generated by random polymerization of ribonucleotides (Joyce and Orgel 2006). Current estimates establish a minimum size about 165 nt long for such a ribozyme (Johnston et al. 2001), a length three to four times that of the longest RNA oligomers obtained by random polymerization on clay mineral surfaces (Huang and Ferris 2003, 2006). To overcome this gap, we have developed a stepwise model of ligation-based, modular evolution of RNA (Briones et al. 2009) whose main conceptual steps are summarized in Figure 1. This scenario has two main advantages with respect to previous hypotheses put forward for the origin of the RNA world: i) short RNA....