In the abbrevated trading day just before July 4, the overall stock market is up slightly. The Dow Jones Industrial Average is up 0.2%, the Nasdaq is up 0.45% and the S&P 500 is up 0.36%. Today, the heavy trading volume seem to be on the winning side. A completed merger has sent a stock soaring nearly 200%, an analyst upgrades a medical research firm, and people may finally think that coal companies have hit rock bottom.

Here are today’s market winners and losers.

Biggest Winners

Shares of Duke Energy (NYSE: DUK) are up 196.26% to $68.97 on trading volume of 1.3 million shares. The firm just completed its merger with Progress Energy for $13.7 billion, creating the largest electric company in the U.S. Progress Energy CEO Bill Johnson has agreed to leave the company, leaving Duke CEO Jim Rogers as the head of the combined company. Before Tuesday, the 52-week high was $23.71.

Shares of Nanosphere (NASDAQ: NSPH) are up 30.95% to $3.30 based on trading volume of 3.9 million shares. The company received a boost after Jefferies placed a buy rating on the company, up from hold, following its approval from the Food and Drug Administration for its Gram Positive blood stream test. Before Tuesday, the 52-week high was $2.59.

Shares of Patriot Coal (NYSE: PCX) are up 24.64% to $1.72 based on trading volume of 7.4 million shares. Shares of the coal company have recently hit a 52- week low of $1.02, about 96% off of the 52-week high of  $24.99. Coal sector stocks have slumped significantly  in 2012 following low natural gas prices.

Biggest Loser

Shares of Chelsea Therapeutics (NASDAQ: CHTP) are down 40.93% to 86 cents based on trading volume of 4.8 million shares. The company announced that the FDA recommended another trial for Northera, a drug used to prevent falls in patients with degenerative physical problems. Before Tuesday, the 52-week low was $1.05.

Samuel Weigley