Compulsory voting papers. Compulsory voting is increasingly resented by citizens in some countries such as Brazil, the largest country where compulsory voting is enforced: at the last presidential election in 2014, some 30 million voters, about 21% of registered voters, did not vote, despite the fact that Brazil has some of the most severe penalties enforced against non voters. A study of a Swiss canton where compulsory voting was enforced found that compulsory voting significantly increased electoral support for leftist policy positions in referenda by up to 20 percentage points. Another study found that the effects of universal turnout in the United
Catalytic converter oxides of nitrogen, they were superseded by three-way converters. Three-way catalytic converters (TWC) have the additional advantage of controlling the emission of nitric oxide (NO) and nitrogen dioxide (NO) (both together abbreviated with and not to be confused with nitrous oxide (NO)), which are precursors to acid rain and smog. Since 1981, "three-way" (oxidation-reduction) catalytic converters have been used in vehicle emission control systems in the United States and Canada; many other countries have also adopted stringent vehicle emission regulations that in effect require three-way converters on gasoline-powered vehicles. The reduction and oxidation catalysts are typically contained in a common