Speaker
Joan Subirats

Description En aquesta sessió analitzarem el paper de les dades i evidències en el policy making. En el debat pluralista característic de les democràcies, les relacions entre evidències, argumentacions i capacitat de persuasió no sempre tenen un recorregut racional o estrictament tècnic. Els criteris de selecció, les argumentacions dels actors i els moments o els escenaris polítics juguen també el seu paper. Analitzarem també si tot plegat es veu o no modificat per la situació de crisi i canvi d'època en el que estem situats

Speaker
Alex Arenas

Description With the advent of the supercomputational era, new challenges emerge concerning the handling and interpretation of huge datasets. In this introductory course, we will review the main techniques to confront such problems and we will provide the main sources of information to start the work of a data scientists. The course will be structured in five parts, corresponding to the main issues in the process of data analysis. 1. Introduction to Big Data: What is? How to deal with? 2. Data reduction techniques: Extracting the essence 3. Data exploration: Statistics and clustering 4. Data exploitation: From data to models 5. Visualization techniques Schedule: April 30. May 2, 6, 7, 10 From 15:00 to 18:00 Interested in attending: send an email to conrad@ffn.ub.es

Speaker
Álvaro Corral

Description The concept of self-organized criticality (SOC) was proposed more than 25 years ago by Bak et al. as a non-equilibrium paradigm for the ubiquity of 1/f noise and the emergence of fractal spatial structures. Although the original ideas came from condensed-matter physics, it became clear soon that geoscience was a fertile ground for SOC, which offered an elegant explanation for the power-law distributed avalanches that characterize the occurrence of landslides, forest fires, and earthquakes, among other catastrophic phenomena. Indeed, SOC postulates a dynamics in which the system energy slowly builds up, up to a point where a local instability appears, releasing energy and propagating rapidly in space. The balance between the slow energy input and the fast dissipation leads the system towards a critical point, which ensures the scale-invariant properties. The plausibility of this mechanism, together with the coincidence between the power-law distributions in the observations and in the models, is a strong support for the SOC paradigm, although the determination of the existence of a critical point is not possible without detailed knowledge of the internal state of the system. In contrast with the opacity of the Earth crust, the atmosphere is "transparent" to many kind of observations. We explain how diverse indicators of atmospheric convection, as the size of rainfall events and the dissipation of energy in tropical cyclones (including hurricanes), are in agreement with the finding of Peters and Neelin about the existence of a sharp increase of tropical rainfall rate as a function of atmospheric water-vapor content, i.e., a critical-point transition which, additionally, acts as an attractor for the state of the atmosphere. This view has important implications not only for the predictability of some atmospheric processes but for the very concept of a chaotic weather. As a by-product, the influence of ocean warming on the energy of tropical cyclones can be clearly evaluated.

Speaker
David Rueda

Description Over the past decade, single-molecule fluorescence studies have elucidated the structure-function relationship of numerous nucleic acids enzymes. In particular, the real-time observation of individual ribozymes has unveiled the dynamic behavior of complex RNA systems in unprecedented detail, revealing the presence of transient intermediate states and their kinetic pathways. Here, we will provide an overview of how single-molecule fluorescence can been used to explore the dynamics of RNA folding and catalysis by present examples from the smallest motifs (e.g., kissing hairpins) to some of the largest ribozymes (such as group II introns and the spliceosome).

Speaker
Nicolas Rubido

Description The relation between structure and function is one of the most studied topics in the theory of complex networks. The structure is a topological representation of the interacting elements forming a network and it is rigorously described by the theory of graphs. The function is related to how the network units interact, exchange information, or dynamically evolve. The work I am presenting deals with analytical solutions for flow networks that satisfy conservation laws [1]. The model for the flow network is stated in terms of resistor networks (weighted symmetric graphs), which have a source node s and a sink node t feeding the system, and a linear relationship between loads (voltages) and flows (currents). Its solutions establish a clear relationship between the topological structure of the networks (namely, adjacency matrix and edge weights, assumed known) and the functional flows passing through nodes and edges (that are a consequence of solving the flow model). [1] Nicolás Rubido, Celso Grebogi and Murilo S. Baptista, EPL, 101 (2013) 68001