Knowing which Select was triggered

hell.jsx

var App = React.createClass({
      userTr: function(user){
            var success = function(res){this.setState(res)};
            var updateUserWith() = function(){
                  return function(value){
                        $.ajax('/users/'+user.id, {property: value}, sucess);
                  };
            }
            return (
                  <Reactable.Tr>
                        <Reactable.Td>
                              <Select onChange={updateUserWith()}></Select>
                        </Reactable.Td>
                  </Reactable.Tr>
            );
      },
      
});