MUMBAI, Aug. 18 -- The Tata Institute of Social Sciences (TISS) will hold its 86th convocation ceremony on August 22 after a last-minute switch in the guest of honour. The institute has invited Dr CS Pramesh, director of the Tata Memorial Hospital, as the chief guest. The institute had originally invited Chief Justice of India Surya Kant to preside over the function but, 48 hours before the event was to be held on August 2, it sent out an email saying the convocation had been postponed due to "unforeseen circumstances". Campus sources said the TISS administration had postponed the convocation fearing protests or other disruptive activities during the function as Justice Surya Kant's reference to unemployed young Indians as "cockroaches" is linked to the recent mass student protests across the country. HTC...