Last month was a wild month for UBS AG, and October is starting off with a bang, as well.  On just the 3rd trading session of the month, we learned that the Swiss bank's co-heads of global equities had resigned over last month’s "rogue" trading incident that resulted in a $2.3 billion loss.  Gone are Francois Gouws and Yassine Bouhara. Each handed in their resignation as they took responsibility for the management of the equities operation, which is where the unauthorized trades occurred.  UBS said others in equities as well as in other areas also would be appropriately disciplined. Succeeding the departing pair are Mike Stewart, who joined UBS from Bank of America Merrill Lynch in July, as head of global equities. This comes just 3 weeks after London trader, Kweku Adoboli, was arrested in the middle of the night and charged with fraud and false accounting - all of which forced UBS to announce a $2.3 billion trading loss.  Another victim of the scandal was CEO Oswald Grübel. UBS is conducting an internal investigation into how a mid-level trader was able to circumvent the bank’s risk controls and pile up such a loss.  Meanwhile, the trader, Mr. Adoboli, remains in police custody and has yet to enter a plea.  The UBS chairman, who previously said that the trader had most likely acted alone, said that the bank’s internal investigation was expected to be completed sooner rather than later. KPMG, the accounting firm, started a separate investigation into the incident on behalf of Swiss and British banking regulators.   [Dealbook, 10/5/11]