Two-stroke scooters are a dominant source of air pollution in many cities.

Fossil fuel-powered vehicles emit significant particulate matter, for example, black carbon and primary organic aerosol, and produce secondary organic aerosol. Here we quantify secondary organic aerosol production from two-stroke scooters. Cars and trucks, particularly diesel vehicles, are thought to be the main vehicular pollution sources. This needs re-thinking, as we show that elevated particulate matter levels can be a consequence of 'asymmetric pollution' from two-stroke scooters, vehicles that constitute a small fraction of the fleet, but can dominate urban vehicular pollution through organic aerosol and aromatic emission factors up to thousands of times higher than from other vehicle classes. Further, we demonstrate that oxidation processes producing secondary organic aerosol from vehicle exhaust also form potentially toxic 'reactive oxygen species'.This work was supported by the Swiss Federal Office for the Environment (FOEN), the Federal Roads Office (FEDRO), the Swiss National Science Foundation (Ambizione PZ00P2_131673, SAPMAV 200021_13016), the EU commission (FP7, COFUND: PSI-Fellow, grant agreement n.° 290605), the UK Natural Environment Research Council (NERC), the French Environment and Energy Management Agency (ADEME, Grant number 1162C00O2) and the Velux Foundation.This is the accepted manuscript version. The final version is available from http://www.nature.com/ncomms/2014/140513/ncomms4749/full/ncomms4749.html

IT Infrastructures Sourcing Challenges and Practices of Exploration-for-Exploitation in Public Sector Organizations: A Delphi Study

Managing information technology infrastructures (ITI) in an effective manner represents a major challenge for any organization and even more for public sector organizations (PSOs) that often lack IT resources and are constrained by tight budgets. Despite the importance of these challenges for practitioners, there is a limited number of studies in this field. Applying the organizational ambidexterity (AO) lens to analyze IT managers’ practices of ITI in public sector, with a specific emphasis on sourcing practices, the present study seeks to fill this gap. We present the outcomes of a Delphi study that involved 40 ITI experts from three sectors: public, private, and academic. Public sector practices of exploration-for-exploitation sourcing are discussed in this paper