The board may either refuse to issue or renew or may suspend or revoke any certificate of registration or approval for any one or a combination of the following causes: (1) Conviction of a felony shown by a certified copy of the record of the court of conviction; (2) gross malpractice or gross incompetency; (3) continued practice by a person knowingly having an infectious or contagious disease; (4) advertising by means of knowingly false or deceptive statements or in violation of section 71-223.02 ; (5) advertising, practicing, or attempting to practice under a trade name or any name other than one’s own; (6) habitual drunkenness or habitual addiction to the use of morphine, cocaine, or other habit-forming drugs; (7) immoral or unprofessional conduct; (8) violation of any of the provisions of the Barber Act or of any valid regulation promulgated by the board pertaining to service charges, sanitation, and the elimination of unfair practices; and (9) any check presented to the board as a fee for either an original license or renewal license or for examination for license or any other fee authorized in the Barber Act which is returned to the State Treasurer unpaid.