when has patient 14836 first received the urine microbiology test in the first hospital visit?
select microbiologyevents.charttime from microbiologyevents where microbiologyevents.hadm_id in ( select admissions.hadm_id from admissions where admissions.subject_id = 14836 and admissions.dischtime is not null order by admissions.admittime asc limit 1 ) and microbiologyevents.spec_type_desc = 'urine' order by microbiologyevents.charttime asc limit 1