What's better than momentum? Mo' momentum.

Let's take a closer look at five of this past week's biggest scorchers.

Company

Aug. 31 Weekly Gain My Watchlist
Sarepta Therapeutics (Nasdaq: SRPT) $15.82 47% Add
Zale (NYSE: ZLC) $5.52 47% Add
Microvision (Nasdaq: MVIS) $2.76 28% Add
Molycorp (NYSE: MCP) $11.51 20% Add
First Solar (Nasdaq: FSLR) $24.77 17% Add

Source: Barron's.

Sarepta Therapeutics climbed on encouraging early clinical-trial results for the biotech's potentially promising Duchenne muscular-dystrophy drug.

Just a couple of days after a larger public rival posted disappointing quarterly results, Zale came through with plenty of bling to go around. The upscale jeweler revealed strong results fueled by a jaw-dropping 11% spike in same-store sales. Zale also now expects to return to profitability in its new fiscal year, silencing worrywarts that were betting that the jewelry store operator would keel over.

There was no company-specific news leading to Microvision's 28% ascent last week, but a short squeeze may have taken place. There were 2.6 million shares sold short as of mid-August, and that results in a high short-interest ratio, given the company's average daily trading volume.

Why is a short squeeze possible? Well, Microvision's PicoP display technology can be incorporated in small mobile gadgets to project larger images. It's a long shot, but naysayers may not want to be short the company over the next couple of weeks as tech's heavyweights introduce new smartphones and tablets.

Molycorp began operations on a new rare-earth elements mine in California. A few days later, Gabelli & Co. upgraded the stock.

Finally, Stifel Nicolaus issued an upbeat note on Geron, suggesting that the biotech should be posting positive results from the clinical trials for two of its cancer drugs by early next year.

More winners for you
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