Analyst Upgrades

• Polo Ralph Lauren (RL) to neutral from underperform at BofA/Merrill.
• Sigma-Aldrich (SIAL) to outperform from market perform at Leerink.
• Petrobras (PBR) to overweight from equal weight at Barclays.
• Silvercorp Metals (SVM) to buy from neutral at UBS.
• PROS (PRO) to buy from hold at Jefferies.
• Power Integrations (POWI) and Monolithic Power (MPWR) to buy from neutral at Roth Capital.
• Diodes (DIOD) to outperform from neutral at RW Baird.
• Whole Foods (WFMI) to hold from sell at Hapoalim.
• Sinclair Broadcast (SBGI) to overweight from neutral at JPMorgan.
• Sappi (SPP) to outperform from neutral at Macquarie.
• Alpha Natural (ANR) to buy from hold at BB&T.
• Watts Water (WTS) to buy from hold at Brean Murray.

Analyst Upgrades

• Oppenheimer upgraded Abercrombie & Fitch (ANF) to outperform from perform as it finds the risk/reward on shares attractive and believes the company's Q4 results and easing comparisons could serve as positive catalysts. The firm set a $46 price target on shares.
• Bernstein upgraded 3M Company (MMM) to outperform from market perform based on expectations the company will continue to beat and raise guidance and that the organic growth rate will continue to improve. The firm raised its target to $99 from $90.
• Roth Capital expects Nvidia (NVDA) to benefit from its new GPU platform Fermi in Q1, resulting in a PC business recovery. Additionally, the firm, which upgraded shares to buy from hold and has a $21 target, expects Nvidia to offset Intel (INTC) declines by selling low-end GPUs compatible with Intel's Pinetrail and Westmere platforms.
• Syngenta (SYT) was upgraded to buy from hold at Collins Stewart.
• Cameron (CAM) was raised to overweight from neutral at HSBC.
• Sigma-Aldrich (SIAL) was lifted to outperform from neutral at Baird.

For 25 years, Steven Halpern, editor of TheStockAdvisors.com, has surveyed the leading financial newsletter advisors asking for their favorite stocks for the coming year. This article is one of 100+ ideas in the Best Stocks for 2008 report.

"My favorite conservative idea for 2008 is Sigma-Aldrich (NASDAQ: SIAL), one of the world's largest providers of research chemicals, reagents, chromatography products, and related products," says Kelley Wright, editor of Investment Quality Trends.

"SIAL distributes more than 100,000 chemical products for use primarily in research and development, diagnosis of disease, and as specialty chemicals for manufacturing.

"The company believes it is the leader in the worldwide market for research chemicals, estimated at about $8.75 billion, with annual revenue growth of 3%-4%. The worldwide market for fine chemicals is estimated at $50 billion, with annual growth of 2%-3%. SIAL projects that it ranks among the top ten players in the fragmented fine chemical industry.

"The company's balance sheet is relatively strong, with a total debt-to-capital ratio of 26.6% as of September 30, 2007. This should allow SIAL to make additional acquisitions and further repurchases of its common stock. SIAL has acquired 83 million (adjusted) of its common shares since November 1999.

The pharmaceutical and biotechnical research demands for high-purity chemicals, solvents, buffers and reference substances is enormous. A recognized leader in the development, manufacture and distribution of the needed materials is headquartered in St. Louis, Missouri.

Sigma-Aldrich Corporation's (NASDAQ:SIAL) biochemical and organic products are used in genomic research, biotechnology processes, pharmaceutical endeavors and the diagnosis of diseases. Its fine chemicals units provide materials for commercial manufacturing applications. Customers are life science firms, universities, government institutions, industrial concerns and hospitals. The company employs over 6,800 and operates in 35 countries.