NEW YORK (TheStreet) -- RATINGS CHANGES

Analog Devices(ADI) - Get Report was downgraded at Citigroup to neutral from buy. Valuation call, based on a 12-month price target of $58, Citigroup said.

Aetna (AET) was downgraded at Citigroup to buy from neutral. Twelve-month price target is $73. Earnings momentum does not appear sustainable, Citigroup said.

Carbo Ceramics(CRR) - Get Report was upgraded at DA Davidson to buy from neutral. Twelve-month price target is $163. Company said that business began to improve in March, DA Davidson said.

Celgene(CELG) - Get Report was upgraded at Piper Jaffray to overweight from neutral. Twelve-month price target is $170. Valuation call, as the stock has lagged over the past couple of months, Piper Jaffray said.

Crown Castle International(CCI) - Get Report was upgraded to buy at TheStreet Ratings.

Barracuda (CUDA) was upgraded to buy at Bank of America/Merrill Lynch. Twelve-month price target is $39.50. Company continues to execute well, Bank of America/Merrill Lynch said.

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Devry (DV) was upgraded at Piper Jaffray to overweight from neutral. Twelve-month price target is $54. Company is seeing strength in health care, and international and margins could rebound in the university unit, Piper Jaffray said.

Dreamworks (DWA) was downgraded at Topeka Capital to hold. Twelve-month price target is $22. Expect further writedowns for Mr. Peabody & Sherman movie, Topeka Capital said.

Fifth Third(FITB) - Get Report was downgraded at BMO Capital to market perform from outperform. Twelve-month price target is $22. Company is seeing some deterioration in core trends, BMO Capital said.

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FMC Technologies(FTI) - Get Report was upgraded at BMO Capital to outperform from market perform. Twelve-month price target is $75. Volatility is declining and profitability is rising, BMO Capital said.

Lamar (LAMR) - Get Report was downgraded at Wedbush to neutral from outperform. Valuation call, based on a 12-month price target of $57, Wedbush said.

Linear Technology (LLTC) was downgraded at Citigroup to neutral from buy. Strong industrial and auto demand is already priced into the stock, Citigroup said. Twelve-month price target is $50.

Landstar(LSTR) - Get Report was upgraded at Deutsche Bank to buy from hold. Twelve-month price target is $70. Fundamentals are improving and the company is expected to buy back more stock, Deutsche Bank said.

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Life Time Fitness(LTM) - Get Report was downgraded at Oppenheimer to perform. Twelve-month price target is $50. Company appears to be facing increased competition, Oppenheimer said.

Maxim(MXIM) - Get Report was upgraded at Citigroup to buy from neutral. Twelve-month price target is $40. Company has secured new design wins, Citigroup said.

Nord Anglia Education (NORD) was initiated at Barclays with an overweight rating. Differentiated business model with EPS upside, Barclays said.

Netscout(NTCT) - Get Report was upgraded at Wunderlich to buy from hold. Twelve-month price target is $46. Company is expanding its addressable market, Wunderlich said.

NuStar Energy(NS) - Get Report was upgraded to buy at TheStreet Ratings.

NXP Semiconductors(NXP) - Get Report 12-month price target, EPS estimates were raised at Jefferies. Increased capital return plan, Jefferies said. Twelve-month price target is $72. Buy rating.

Stancorp (SFG) was upgraded at Sterne Agee to neutral from underperform. Twelve-month price target is $67. Valuation call, as the stock is down 10% year to date, Sterne Agee said.

Time Warner Cable (TWC) was upgraded at Pivotal Research to buy from hold. Twelve-month price target is $175. Company is seeing higher subscriber growth, Pivotal Research said.

Under Armour(UA) - Get Report was upgraded at Stifel Nicolaus to buy from hold. Twelve-month price target is $65. Stock is attractive, following a pullback after strong quarterly results, Stifel Nicolaus said.

Wells Fargo(WFC) - Get Report was upgraded at BMO Capital to outperform from market perform. Twelve-month price target is $55. Company deserves a premium valuation, BMO Capital said.

Stock Comments / EPS Changes

American Airlines(AAL) - Get Report 12-month price target was raised at Barclays. Capable management team is executing turnaround strategy, Barclays said. Twelve-month price target is $41. Equal Weight rating.

Aetna (AET) 12-month price target was increased at Barclays. Strong first quarter with boost to guidance, Barclays said. $87 price target and overweight rating.

Amazon.com(AMZN) - Get Report 12-month price target was lowered at UBS. Little potential for EBITDA margin expansion, UBS said. Twelve-month price target is $365. Neutral rating.

Bright Horizons Family Solutions(BFAM) - Get Report 12-month price target was raised at Barclays. Driven by capital allocation strategy, Barclays said. Twelve-month price target is $50. Overweight rating.

Caterpillar(CAT) - Get Report estimates, 12-month price target was boosted at Credit Suisse. Twelve-month price target is now $117. Estimates were also increased, given the company's new guidance, Credit Suisse said. Outperform rating.

Caterpillar 12-month price target was lifted at UBS to $106. Strong operating margin improvement with healthy construction segment. Neutral rating.

Corning(GLW) - Get Report 12-month price target was lowered at Jefferies to $17. Slowing growth with core LCD glass business, Jefferies said. Hold rating.

Hershey(HSY) - Get Report earnings estimates, 12-month price target were cut at Credit Suisse. Shares are now seen reaching $108. Estimates were also reduced, as the company is seeing lower earnings quality, Credit Suisse said. Outperform rating.

Las Vegas(LVS) - Get Report numbers were raised at Credit Suisse. Twelve-month price target is $87. Estimates were also increased, as Macau continues to drive growth, Credit Suisse said. Outperform rating.

Timken(TKR) - Get Report price target, EPS estimates were raised at Jefferies. Strong operating start to year with buyback program starting in first quarter. Twelve-month price target is $75. Buy rating.

Time Warner Cable price target, EPS estimates were raised at Jefferies. Driven by strong volumes, second-quarter price increases and easier comps, Jefferies said. Twelve-month price target is $150. Hold rating.

USG (USG) price target, earnings estimates were cut at Jefferies. Driven by lower wallboard prices and softer demand backdrop, Jefferies said. Twelve-month price target is $36. Buy rating.

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This article was written by a staff member of TheStreet.