Compulsory voting , 22 countries were recorded as having compulsory voting. Of these, only 10 countries (additionally one Swiss canton and one Indian state) enforce it. Of the 30 member states of the Organisation for Economic Co-operation and Development, 10 had forms of compulsory voting. These are the countries and sub-national entities that enforce compulsory voting: Countries that have compulsory voting by law but do not enforce it: Although voting in a country may be compulsory, penalties for failing to vote are not always strictly enforced. In Australia and Brazil, providing a legitimate reason for not voting (such as illness) is accepted.
Catalytic triad enzyme and act in concert with other residues (e.g. binding site and oxyanion hole) to achieve nucleophilic catalysis. These triad residues act together to make the nucleophile member highly reactive, generating a covalent intermediate with the substrate that is then resolved to complete catalysis. Catalytic triads perform covalent catalysis using a residue as a nucleophile. The reactivity of the nucleophilic residue is increased by the functional groups of the other triad members. The nucleophile is polarised and oriented by the base, which is itself bound and stabilised by the acid. Catalysis is performed in two stages. First, the activated nucleophile