This week's roundup begins with some of our favorite stories from the annual meeting of AAAS in Boston. Are we miscounting calories ? Will space make you go blind ? Do we live inside a mathematical equation ? Check out our complete coverage  from the meeting, including pictures, podcasts, and 6-Second Science  videos!
Researchers have figured out how to get drug-delivering nanoparticles past the immune sentries that wait to gobble them up and thwart their medical missions. A molecular "passport" allows the particles to mimic human cells and sneak past the immune guards so that they can deliver drugs designed to attack tumors and other specific targets.
Lots of studies have shown that girls learn language faster and earlier than boys do. Figuring out exactly why this is so has been difficult as it involves teasing apart the effects of nature versus nurture. But now scientists have found that FOX2P, a gene essential to human communication, expresses itself differently in girls than it does in boys. Although researchers caution against drawing broad conclusions, the discovery may partially explain exactly why language skills vary between the sexes.
Just like humans have names, bottlenose dolphins have signature whistles. Because dolphins are such good mimics, scientists looked into whether they imitate each other's whistles—the aquatic equivalent of calling someone's name. It turns out that they do, but they're much more selective than humans about whose name they call, choosing to imitate only the whistles of their closest social partners. Mothers and calves, and very close male friends, are the only pairs that researchers have seen getting shout-outs so far.
The head of the National Institutes of Health and a key congressional supporter have warned that biomedical research in the United States will be badly damaged if sequestration goes into effect on 1 March. They say that scientific progress will slow and clinical trials will be delayed if the budget cuts proceed as planned.
A Turkish scientist is facing a 25-month prison sentence for forbidding students wearing headscarves from entering his classroom. The scientist says he was simply upholding the Turkish constitution, which does not allow the display of religious symbols or affiliations in government-funded buildings. Turkish academics say his sentence is part of an ongoing conservative government campaign to intimidate secular intellectuals.