We are doing some essential maintenance work and you will not be able to register or update your profile setting until we've finished, which should be at about 9pm this evening.
We apologise for any inconvenience - you will be able to register shortly. In the mean time you will still be able to log in as usual.
An atmosphere of fear on campuses has served to mute expression and limit academic freedom, but action can still be taken to fight back, says Debora Diniz