Os Colóquios do Departamento de Física serão realizados através de sessões Zoom no endereço:
O próximo Colóquio do Departamento de Física realiza-se no dia 4 de Novembro às 16h00
"COVID-19, Delphi, IX-XI, and Plato: A data-driven epidemiological model to explain the COVID-19 pandemic"
Speaker: Pedro Sebastião , Physics Department - Instituto Superior Técnico / CeFEMA
Abstract: "Accurate models are fundamental to understand the dynamics of the COVID-19 pandemic and to evaluate different mitigation strategies. Here, we present a multi-compartmental model that fits the epidemiological data for eleven countries, despite the reduced number of fitting parameters. This model consistently explains the data for the daily infected, recovered, and dead over the first six months of the pandemic. The good quality of the fits makes it possible to explore different scenarios and evaluate the impact of both individual and collective behaviors and government- level decisions to mitigate the epidemic. "
Short Bio: "Pedro José Sebastião is an experimental physics professor with the Department of Physics of Instituto Superior Técnico, Universidade de Lisboa. Following the work for his PhD thesis, in 1993, on molecular dynamics in liquid crystals with peculiar polymorphisms by proton nuclear magnetic resonance (NMR) relaxometry, he has investigated a large number of condensed matter systems using NMR. His aim has been to understand the interdependence between molecular organisation and molecular dynamics. Since NMR relaxometry can provide information about molecular motions in different time and length scales, P.J. Sebastião has been always concerned in being able to cover a broad range of NMR frequencies from hundreds of MHz to kHz in NMR relaxometry studies. Fast Field-Cycling relaxometry has proved to be crucial to obtain information below the MHz range and, on the past 20 years, he has devoted some of his efforts to the development of new, more efficient, FFC NMR relaxometry equipment. P.J. Sebastião on his research activity has investigated molecular order and dynamics in liquid crystals (i.e. materials that present thermodynamically stable phases between the isotropic and the solid phases, where properties, like fluidity, characteristic of liquids, are found simultaneously with properties characteristic of crystals, like birefringence), dendrimers, polymers (e.g. in-bulk, membranes, nano composite systems), electrolytes (e.g. pure ionic liquids, polymer electrolytes, salt solutions), heterogeneous systems (e.g. liquid crystals in nano-porous glasses, small molecules dispersed in porous membranes). As examples, in the liquid crystals area he has investigated blue phases, nematic phases: N, N*, Ntb; smectic phases: A, Ad, A2, C, B, chiral phases C* (e.g. ferroelectric, anti-ferroelectric), TGBA*, and TGBC*. All these systems present different types of molecular organisation that affect molecular dynamics, for which the development of relaxation models has proved to be essential. In order to achieve an efficient analysis of experimental data in general and of NMR data in particular, P.J. Sebastião developed an open access web interface to his model fitting software package made available in 2009 (fitteia.org). The interface can be used not only to fit simple models (e.g linear or otherwise polynomial equations), but more importantly the complex models used to interpret the spin-lattice relaxation data obtained in NMR relaxometry studies (e.g. models for collective motions, motions restricted by walls, paramagnetic relaxation, molecular entanglement, etc..). The full power of the developed software has been put into evidence in many different studies, in particular those where global multidimensional fits are required taking into account dependences on frequency, temperature, molecular alignment, nuclear spin, etc.. The functions' library already includes models suited for many of the systems addressed by the author in previous studies but new user defined models can be easily added to the library for the benefit of other users or private use alone. "
CALENDARIZAÇÃO DOS COLÓQUIOS DO DEPARTAMENTO DE FÍSICA
1º Semestre, ano letivo 2020/2021
|14/Out.||Patrícia Gonçalves||Planetary Radiation Environments and the Exploration of the Solar System||Physics Department - Instituto Superior Técnico / LIP||2 e 3|
|21/Out.||Petra Rudolf||Molecular Motors and Switches at Surfaces||Zernike Institute for Advanced Materials,
University of Groningen, Netherlands *||3 e 4|
|4/Nov.||Pedro Sebastião||COVID-19, Delphi, IX-XI, and Plato||Physics Department - Instituto Superior Técnico / CeFEMA||1 e 3|
|18/Nov.||Joana Sá||TBA||Physics Department - Instituto Superior Técnico / LIP||2 e 3|
|25/Nov.||José Sande e Lemos||Black Holes: from Dawn to Nobel||Physics Department - Instituto Superior Técnico / CENTRA||1 e 2|
|16/Dez.||Richard Genzel||Testing the Massive Black Hole Paradigm and GR with Infrared||Max Planck Institute for Extraterrestrial Physics, Garching, Germany||1 e 3|
Cada Colóquio desta série faz parte de um dos ciclos seguintes:
1. The end of Nature
2. Trends and frontiers in Physics
3. Physics at the core of Technology
4. Paths and ways for a graduate in Physics
Docentes responsáveis: Teresa Peña, Amaro Rica da Silva e Pedro Assis