BioFuel Energy Corp. (NASDAQ:BIOF), CytRx Corporation (NASDAQ:CYTR) and YuMe Inc (NYSE:YUME) are this Friday’s top midday gainers. Ending the week on a sour note are today’s midday losers – Advanced Micro Devices, Inc. (NYSE:AMD), iPath S&P 500 VIX Short Term Futures TM ETN (NYSEARCA:VXX) and Teekay LNG Partners L.P. (NYSE:TGP).

BioFuel Energy

BioFuel Energy Surges

BioFuel Energy Corp. (NASDAQ:BIOF) hit noon up +11.99% for the day. It’s been a big week for the  energy firm following confirmation Wednesday that Greenlight Capital will fully participate in an upcoming rights offering for it.  The price of BIOF has climbed +26.65% over the past five days.

CytRx Corporation (NASDAQ:CYTR) climbed +7.76% midday today. A new Q1 acquisition for George Soros, CytRx is a biopharmaceutical research and development company that specializes in oncology. It has had a rough go in 2014, its price falling -43.83% YTD.

Last on today’s list of midday losers is YuMe Inc (NYSE:YUME), up +7.07%. The video advertising company is likely feeling the effects TubeMogul’s IPO, though it’s been a difficult year for ad tech stocks overall. YuMe, another Soros holding, is down -15.03% year-to-date.

Advanced Micron Devices Inc. Dives Following Results Release

Advanced Micro Devices, Inc. (NYSE:AMD) posted a loss of -17.94% midday today. Yesterday, the company reported financial results, missing the mark on earnings expectations and failing to impress investors even with the narrowing of its second-quarter loss. Julian Robertson holds 315,000 shares of AMD.

iPath S&P 500 VIX Short Term Futures TM ETN (NYSEARCA:VXX) slipped -6.31% today – this Barron’s piece provides some interesting insights as to why. The exchange-rated note is a first quarter buy for George Soros, who purchased 450,000 VXX shares.

Teekay LNG Partners L.P. (NYSE:TGP) takes the third and final spot on this Friday’s list of midday losers, its price falling -5.43%. The long-time Leon Cooperman holding announced the pricing of a 2.8 million common unit spot secondary offering on Thursday. Despite today’s dip, TGP’s price is up +4% in 2014.