Perturbation Centrality and Turbine: A Novel Centrality Measure Obtained Using a Versatile Network Dynamics Tool

Analysis of network dynamics became a focal point to understand and predict changes of complex systems. Here we introduce Turbine, a generic framework enabling fast simulation of any algorithmically definable dynamics on very large networks. Using a perturbation transmission model inspired by communicating vessels, we define a novel centrality measure: perturbation centrality. Hubs and inter-modular nodes proved to be highly efficient in perturbation propagation. High perturbation centrality nodes of the Met-tRNA synthetase protein structure network were identified as amino acids involved in intra-protein communication by earlier studies. Changes in perturbation centralities of yeast interactome nodes upon various stresses well recapitulated the functional changes of stressed yeast cells. The novelty and usefulness of perturbation centrality was validated in several other model, biological and social networks. The Turbine software and the perturbation centrality measure may provide a large variety of novel options to assess signaling, drug action, environmental and social interventions. The Turbine algorithm is available at: http://www.turbine.linkgroup.huComment: 21 pages, 4 figues, 1 table, 58 references + a Supplement of 52 pages, 10 figures, 9 tables and 39 references; Turbine algorithm is available at: http://www.turbine.linkgroup.h

Tendência dos acidentes de trânsito em Campinas, São Paulo, Brasil: importância crescente dos motociclistas Trends in traffic accidents in Campinas, São Paulo State, Brazil: the increasing involvement of motorcyclists

Com o objetivo de descrever a tendência de ocorrência de acidentes de trânsito, sua mortalidade, tipo de veículo envolvido, tamanho da frota e perfil das vítimas em Campinas, São Paulo, Brasil, entre 1995 e 2008, foram estimadas taxas de motorização e ocorrência de acidentes, letalidade, mortalidade proporcional, taxas de mortalidade e razões entre taxas. A frota de motocicletas cresceu 241%. Apesar da queda da letalidade dos acidentes de ocupantes de motos entre 2000 e 2008, esta categoria representou 49,3% do total de acidentes fatais em vias públicas em 2008. As motos foram responsáveis pelas maiores taxas de atropelamento (66,7 atropelados/mil acidentes) e de atropelamentos seguidos de morte (4 óbitos/mil acidentes). Os homens mantiveram risco de morrer no trânsito muito superior ao das mulheres. Nos atropelamentos, predominaram elevadas taxas de mortalidade em idosos; entre os ocupantes de veículos, os mais atingidos foram os de 15 a 29 anos. Na faixa de 15 a 39 anos, entre 2006 e 2008, quase 80% eram ocupantes de moto. Ações pluri-institucionais devem priorizar a prevenção de acidentes entre motociclistas.<br>In order to describe trends in traffic accidents, mortality, vehicle types, fleet sizes, and victims' characteristics in Campinas, São Paulo State, Brazil, from 1995 to 2008, this study analyzed vehicle rates, traffic accident rates per inhabitant and per vehicle, case-fatality rates, proportional mortality, mortality rates, and rates ratios. The motorcycle fleet increased 241%. Although the case-fatality rate of motorcycle users from 2000 to 2008 decreased, in 2008 they accounted for 49.3% of fatal accidents on public byways in Campinas. Motorcycles were responsible for the highest run-over rate (66.7 pedestrians/1,000 accidents) and highest pedestrian fatality rate (4 deaths/1,000 accidents). Men showed much higher mortality rates than women. Pedestrian victims were mainly elderly; most vehicle occupants in traffic accidents were in the 15 to 29-year age bracket. From 2006 to 2008, nearly 80% of vehicle users 15 to 39 years of age were motorcyclists. Motorcycle accident prevention should be a priority, using multi-institutional measures