Any claim under section 39 or any appeal under sections 76, 77 and 79 or any revision under section 78 or any application for review under section 81 may, notwithstanding anything contained in those sections, be admitted after the period specified for preferring such claim, appeal, revision or making such application for review by or under this Act, if the claimant, appellant or applicant satisfies the appellate authority, Tribunal, District Court or the prescribed authority, as the case may be, that he had sufficient cause for not preferring the claim or appeal or revision or making the application for review within such period.