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How do you make nanodiamonds? Merge two carbon ‘onions’
Anup Shah/naturepl.com
IN BRIEF Glimpsing the birth of a nanodiamond
Failed pregnancies follow monkey troop takeover WHEN a new leader takes control of a troop of gelada monkeys, he is likely to kill the offspring of his predecessor. His arrival is also bad news for young yet to be born: they’ll be aborted within weeks. Named for Hilda Bruce who first observed it in mice, the “Bruce effect” is common in lab animals. In fact, some biologists suspect it is an artefact of keeping animals in labs. Jacinta Beehner of the University of Michigan in Ann Arbor and colleagues have now found evidence of the effect in wild geladas (Theropithecus gelada), an Ethiopian monkey related to baboons.
They found that the number of births fell sharply in the six months after a new dominant male took over a group, suggesting females were aborting their fetuses. As a check, Beehner took hormone samples from females’ faeces, allowing her to track 60 pregnancies closely. Of nine failures, eight occurred in the two weeks after the father was replaced (Science, DOI: 10.1126/ science.1213600). Beehner says the strategy makes sense, because females don’t want to waste energy on offspring likely to be killed after they are born. We don’t know how the females do it, says Peter Brennan of the University of Bristol, UK, who was not part of the study. It may simply be a response to the stress of the takeover.
Type 1 diabetics still make insulin PEOPLE with type 1 diabetes may continue making their own insulin for decades, challenging assumptions that they stop production within a couple of years of diagnosis. The surprise finding suggests that some of the pancreatic cells responsible for making the hormone still survive in those with diabetes, raising hopes that they can be regenerated.
“People thought [the cells] all decay away after about a year,” says Denise Faustman of Massachusetts General Hospital in Boston, who led the team that made the find. Faustman’s team screened the blood of 182 people with diabetes to search for C-peptide, a protein made exclusively during insulin production. Faustman found it in 80 per cent of people who had
been diagnosed with type 1 diabetes within the last five years. She even detected it in 10 per cent of those who had been diagnosed 31 to 40 years previously (Diabetes Care, DOI: 10.2337/dc11-1236). Faustman says the findings raise hopes that it may be possible for people to recover from the condition, if surviving insulinproducing cells can be protected or regenerated, as has been tried using stem cell and immune re-tuning treatments.
STRANGE parents should have unusual offspring. Sure enough, when two carbon “onions” collide, a nanodiamond is born. It’s an insight into the weird chemistry that arises in outer space. Meteorites are home to diamonds a few nanometres wide but how these tiny crystals form is a mystery. A precursor could be the equally exotic nested carbon cages called carbon onions that lurk in interstellar space. When Nigel Marks of Curtin University in Perth, Australia, and colleagues simulated collisions between two carbon onions, and carbon onions and dust grains, both produced nanodiamonds (Physical Review Letters, DOI: 10.1103/ PhysRevLett.108.075503). Clouds of dust around ageing, carbon-rich stars and dusty planet-forming discs could host such collisions. When the dust gets baked into asteroids, chips can fall to Earth as meteorites.
Towering penguin takes the biscuit AN EXTINCT penguin that lived in New Zealand 27 million years ago may have been the tallest ever. At 1.3 metres tall, Kairuku grebneffi would have looked down on today’s 1-metre-tall emperor penguin. It has a rival for the tallest penguin crown, though, as a few fossil bones of a penguin that may have been slightly taller were found in Peru in 2007. The new find is more complete than the Peruvian one, so its height is known more accurately, says Daniel Ksepka of North Carolina State University in Raleigh, in an upcoming paper in the Journal of Vertebrate Paleontology. K. grebneffi had a surprisingly slender body, Ksepka says. “Modern penguins are chubby little dudes.” 3 March 2012 | NewScientist | 17
IN BRIEF Glimpsing the birth of a nanodiamond
Failed pregnancies follow monkey troop takeover WHEN a new leader takes control of a troop of gelada monkeys, he is likely to kill the offspring of his predecessor. His arrival is also bad news for young yet to be born: they’ll be aborted within weeks. Named for Hilda Bruce who first observed it in mice, the “Bruce effect” is common in lab animals. In fact, some biologists suspect it is an artefact of keeping animals in labs. Jacinta Beehner of the University of Michigan in Ann Arbor and colleagues have now found evidence of the effect in wild geladas (Theropithecus gelada), an Ethiopian monkey related to baboons.
They found that the number of births fell sharply in the six months after a new dominant male took over a group, suggesting females were aborting their fetuses. As a check, Beehner took hormone samples from females’ faeces, allowing her to track 60 pregnancies closely. Of nine failures, eight occurred in the two weeks after the father was replaced (Science, DOI: 10.1126/ science.1213600). Beehner says the strategy makes sense, because females don’t want to waste energy on offspring likely to be killed after they are born. We don’t know how the females do it, says Peter Brennan of the University of Bristol, UK, who was not part of the study. It may simply be a response to the stress of the takeover.
Type 1 diabetics still make insulin PEOPLE with type 1 diabetes may continue making their own insulin for decades, challenging assumptions that they stop production within a couple of years of diagnosis. The surprise finding suggests that some of the pancreatic cells responsible for making the hormone still survive in those with diabetes, raising hopes that they can be regenerated.
“People thought [the cells] all decay away after about a year,” says Denise Faustman of Massachusetts General Hospital in Boston, who led the team that made the find. Faustman’s team screened the blood of 182 people with diabetes to search for C-peptide, a protein made exclusively during insulin production. Faustman found it in 80 per cent of people who had
been diagnosed with type 1 diabetes within the last five years. She even detected it in 10 per cent of those who had been diagnosed 31 to 40 years previously (Diabetes Care, DOI: 10.2337/dc11-1236). Faustman says the findings raise hopes that it may be possible for people to recover from the condition, if surviving insulinproducing cells can be protected or regenerated, as has been tried using stem cell and immune re-tuning treatments.
STRANGE parents should have unusual offspring. Sure enough, when two carbon “onions” collide, a nanodiamond is born. It’s an insight into the weird chemistry that arises in outer space. Meteorites are home to diamonds a few nanometres wide but how these tiny crystals form is a mystery. A precursor could be the equally exotic nested carbon cages called carbon onions that lurk in interstellar space. When Nigel Marks of Curtin University in Perth, Australia, and colleagues simulated collisions between two carbon onions, and carbon onions and dust grains, both produced nanodiamonds (Physical Review Letters, DOI: 10.1103/ PhysRevLett.108.075503). Clouds of dust around ageing, carbon-rich stars and dusty planet-forming discs could host such collisions. When the dust gets baked into asteroids, chips can fall to Earth as meteorites.
Towering penguin takes the biscuit AN EXTINCT penguin that lived in New Zealand 27 million years ago may have been the tallest ever. At 1.3 metres tall, Kairuku grebneffi would have looked down on today’s 1-metre-tall emperor penguin. It has a rival for the tallest penguin crown, though, as a few fossil bones of a penguin that may have been slightly taller were found in Peru in 2007. The new find is more complete than the Peruvian one, so its height is known more accurately, says Daniel Ksepka of North Carolina State University in Raleigh, in an upcoming paper in the Journal of Vertebrate Paleontology. K. grebneffi had a surprisingly slender body, Ksepka says. “Modern penguins are chubby little dudes.” 3 March 2012 | NewScientist | 17