A 28-YEAR-OLD PhD  student at the Indian Institute of Technology Kanpur ended her life by hanging herself from the ceiling hook here on Thursday, the fourth such case inthe last one year, police said. Pragati Kharya, a resident of Sanigawan in Kanpur who was pursuing a PhD in Earth Sciences, committed suicide inside her hostel room D-116 in hall number-4 during the intervening night, but the matter came to light on Thursday noon, they said. Her hostel mates informed theIIT-Kauthorities who in turn alerted the police.