Unfortunately raised in Los Alamos (4)
I believe the answer is:
alas
'unfortunately' is the definition.
('alas' is used to express regret)
'raised in los alamos' is the wordplay.
'raised' says the letters should be written backwards (going up in a down clue).
'in' indicates the answer is hidden within the clue.
'sala' can be found hidden inside 'los alamos'.
'sala' backwards is 'ALAS'.
(Other definitions for alas that I've seen before include "Sad expression" , "Sadly, unfortunately" , "Woeful expression" , "Unhappily" , "Expression of regret" .)