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Top stories: A safe arrival for Juno, ‘supersniffer’ mice, and a robotic stingray powered by light—and muscle cells
(Left to right): NASA/JPL; schankz/shutterstock; Courtesy of Sally Szuster

Top stories: A safe arrival for Juno, ‘supersniffer’ mice, and a robotic stingray powered by light—and muscle cells

Why knee injuries often don’t heal

If you fall on the ski slopes or slip on a patch of ice, you’ll probably be better off if you break your leg than if you rip the cartilage in your knee. Unlike bones, your cartilage is never going to regrow or heal, according to a new study based in part on fallout from past nuclear explosions.

Hate journal impact factors? New study gives you one more reason

Scientists have a love-hate relationship with the journal impact factor, the measurement used to rank technical journals by prestige. In an attempt to shed some light on the metric, a group of researchers and journal editors released a data set and analysis of the citation counts used to calculate this magical number this week. And their conclusions are likely to delight the impact factor’s critics.

Update: Canada's health funder agrees to meet with researchers outraged by peer-review changes

Someday, historians might call it the Peer Uprising. Nearly 1000 Canadian researchers last week demanded that their government immediately reverse “radical” changes that the nation’s main biomedical research funder has made to its grantsmaking process, arguing that they are wreaking havoc on the science community. In response, officials at the Canadian Institute of Health Research agreed to meet with representatives of the outraged group of researchers.

Robotic stingray powered by light-activated muscle cells

Kevin Kit Parker wants to build a human heart. His young daughter loves the New England Aquarium in Boston. In a new report, father’s and daughter’s obsessions have combined in an unlikely creation: a nickel-sized artificial stingray whose swimming is guided by light and powered by rat heart muscle cells.

Jupiter, meet Juno: NASA spacecraft settles in to begin its mission

This week, NASA controllers received confirmation that their latest planetary probe, Juno, had arrived safely at Jupiter. Juno will peer through Jupiter’s outer veil of clouds to study its structure deep into the interior to study the planet’s origin and evolution.

These “supersniffer” mice could one day detect land mines, diseases

Doctors and soldiers could soon place their trust in an unusual ally: the mouse. Scientists have genetically engineered mice to be ultrasensitive to specific smells, paving the way for animals that are “tuned” to sniff out land mines or chemical signatures of diseases like Parkinson’s and Alzheimer’s.

Now that you’ve got the scoop on this week’s hottest science news, come back Monday to test your smarts on our weekly quiz!