At a Glance
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10.26.09 One climate-change report cardStockholm University professor Johan Rockstrom and colleagues crafted this attempt at visualizing climate change for the journal Nature. Five of their 10 indicators fell within safe limits, marked in green. However, the index gave failing grades to global extinction rates, carbon dioxide emissions, and the level of nitrogen removed from the atmosphere for human use (such as fertilizer). |
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08.25.09 How hackers attack websitesHackers can take over thousands of infected computers, then send them secret commands without the PC's owner ever noticing. Once corralled, these "botnets" can be used to send spam or launch denial of service (DoS) attacks that overwhelm websites. |
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08.20.09 Space wasteWater is a valuable resource, especially in space, where it cannot be easily resupplied. Urine, which undergoes the most thorough waste treatment, is purified for reuse: |
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08.07.09 How WiMax worksOnce installed throughout a city, WiMax could make Wi-Fi obsolete, as everyone would have access to the Internet from anywhere within the network range. |
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08.07.09 Biodiesel from algaeHigh oil prices and advances in biotech over the past decade have refueled the algae biofuel race. |
