After the hearing and any investigation, the commission shall make all findings, findings of fact, recommended decisions and orders, and decisions and orders in writing, which findings, findings of fact, recommended decisions and orders, and decisions and orders shall be entered of record. Except as provided in the State Employees Collective Bargaining Act, the final decision and order or orders shall be in effect from and after the date therein fixed by the commission, but no such order or orders shall be retroactive except as provided otherwise in the Industrial Relations Act. Except as provided otherwise in the Industrial Relations Act, in the making of any findings or orders in connection with any such industrial dispute, the commission shall give no consideration to any evidence or information which it may obtain through an investigation or otherwise receive, except matters of which the district court might take judicial notice, unless such evidence or information is presented and made a part of the record in a hearing and opportunity is given, after reasonable notice to all parties to the controversy of the initiation of any investigation and the specific contents of the evidence or information obtained or received, to rebut such evidence or information either by cross-examination or testimony.