Small stocks treaded water for most of the day Tuesday before sinking into negative territory along with the Nasdaq, but Astea International ( ATEA) managed to surface as a big winner.

The Horsham, Pa., management-software developer soared 44.1% to $8.10 in furious trading after it swung to a first-quarter profit of $1.3 million, or 36 cents a share, compared with a trenchant year-ago loss. Revenue more than doubled from last year to $7.8 million.

Ocean shipper TBS International ( TBSI) was rolling in first-quarter profits of $15.2 million, or 54 cents a share (excluding a special item) -- nearly doubled from adjusted year-ago earnings and 14 cents ahead of two analysts' estimates, per Thomson Financial. Shares jumped 11.3% to $19.79.

Elsewhere, Oregon broker Paulson Capital ( PLCC) bounced 16.7% to $5.60 after it swung to a first-quarter profit, and Californian aircraft lessor AeroCentury ( ACY) shot up 11.4% to $19.87 on sharply higher earnings.

Also climbing today was HemoSense ( HEM) after inking a deal to supply Laboratory Corp. of America ( LH) with its portable INRatio PT/INR monitoring system, which gauges blood-clotting time in order to reduce the risk of stroke. San Jose, Calif.-based HemoSense leapt 10.9% to $7.10 as Laboratory Corp. was unmoved in recent trading.

Among sinking small-cap stocks today, however, Michigan's Aurora Oil & Gas ( AOG) tumbled 20.1% to $1.83 after Jeffries cut the driller to hold from buy following a penny-a-share loss in the first quarter on revenue that was just shy of consensus.

The plunge helped pull down the Russell 2000 Index, which lately lost 0.4% to 819.38. The S&P SmallCap 600 meanwhile shed 0.2% to 426.70.

Another driller, Denver-based Infinity Energy Resources ( IFNY) narrowed its first-quarter loss but also saw an 11.2% sales drop from last year to $2.1 million. Shares recently lost 8.4% to $3.49. China Precision Steel ( CPSL) was also hurting, recently off 12.6% at $3.35 after continuing-operations income plummeted 58.3% from last year to a nickel a share.

A downgrade, finally, sharply reversed ICF International's ( ICFI) fortunes. The Virginian management-services firm left first-quarter expectations in the dust, but a Jeffries analyst nevertheless said he believes it's headed for a deceleration, and cut the stock to hold from buy. After an after-hours surge Monday, shares plunged 13.3% below yesterday's closing price to $20.57.