Penalty revision strengthens sanctions for failure to file returns and tightens the deeming rule for concealment. Amendment to section 271 revises penalty provisions by replacing certain clauses, prescribing a minimum and maximum monetary penalty for specified failures, increasing a multiplicative penalty factor, omitting an existing proviso, substituting an Explanation that deems failure to furnish a return by a person not previously assessed to be concealment where taxable income is found, narrowing another explanatory reference, adding an exclusion for specified adjustments and additional tax, omitting a prior sub-section, and providing transitional application to earlier assessment years.