The PowerShares Lux Nanotech ( PXN) was one of few winners among exchange-traded funds during Monday's session. Holding Altair Nanotechnologies ( ALTI) was surging 12.3% after AES Corp. ( AES) said it bought nearly 900,000 shares of Altair. The ETF was higher by 12 cents, or 0.7%, to $16.97.

The Internet Architecture HOLDRs ( IAH) ETF was also trading higher. Holdings Cisco ( CSCO) and Apple ( AAPL) were tacking on 1%. The ETF was adding 14 cents, or 0.3%, to $40.80.

On the negative side, foreign-market-related ETFs were dropping as overseas markets were under pressure again. Earlier, Tokyo's Nikkei lost 2.3%, Hong Kong's Hang Seng slid 4%, and China's Shanghai and Shenzhen 300 slumped 1.3%. Other markets in Europe also lost ground.

The iShares MSCI Malaysia Index ( EWM) was falling 5.6% to $9.10. The iShares FTSE/Xinhua China 25 Index ( FXI) was losing 2.7% to $92.54. The Vanguard Emerging Markets Stock ( VWO) ETF was down 1.9% to $71.81

Bundled securities following the energy sector were also among the worst performers. The front-month April contract for crude oil was recently falling by $1.84 to $59.80 a barrel. The iPath Goldman Sachs Crude Oil ( OIL) ETF was recently shedding 3.1% to $36.36. The United States Oil ( USO) ETF was giving back 3% to $49.46. The Oil Services HOLDRs ( OIH) ETF slid 1.4% to $132.75.

ETFs tracking metals and mining were also among the losers Monday. Gold was falling by $1.90 to $642.20 an ounce, and silver was giving back 16 cents to $12.80 an ounce.

The iShares Silver Trust ( SLV) was lower by 1.7% to $126.60. The streetTRACKS Gold Shares ( GLD) ETF was shedding 0.5% to $63.38. The iShares Comex Gold Trust ( IAU) was losing 0.5% to $63.37.