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Earth's magnetic pole may not flip soon
Matjaž Humar and Seok Hyun Yun
in Brief Autistic kids can read body language
Droplets of oil turn human cells into living lasers INDIVIDUAL cells have been made to act like tiny lasers, allowing them to be monitored more accurately. Making cells shoot laser beams may sound fantastical, says Matjaž Humar of Harvard Medical School in Cambridge, Massachusetts, but the techniques are surprisingly straightforward. “It’s actually super-easy.” Humar and his colleagues developed three ways to get cells to emit visible light. The first involved injecting each one with a tiny oil droplet – this formed an optical cavity in the cell that could be filled with fluorescent dye. When a light pulse was shone onto the cavity, the dye atoms
entered an excited state, emitting light. In a less invasive procedure, polystyrene beads were scattered in a Petri dish filled with macrophages, a type of white blood cell that ingests foreign material – such as the beads. Once ingested, the 10-micrometre-wide beads performed the same function as the oil droplets, acting as an optical cavity capable of emitting highly focused laser light. The final mechanism involved exploiting the fatty droplets already found within living cells (the yellow spheres above). “We all have these fat cells inside our tissue. We are all made of lasers,” says Humar (Nature Photonics, DOI: 10.1038/nphoton.2015.129). The technology could be used to monitor the spread of tumour cells or the behaviour of immune cells.
Earth’s magnetic pole may not flip soon FLIPPING heck! Deposits from fires set by farmers centuries ago reveal that Earth’s magnetic field dramatically weakened in the past without actually flipping – suggesting that current field weakening might not necessarily lead to a pole swap either. Earth’s poles have swapped in the past, but without a regular pattern, says Rory Cottrell of the University of Rochester in New 14 | NewScientist | 1 August 2015
York. This means we don’t know when they will flip again – but many suspect it might be soon: the field has been weakening since about 1840. A flip may affect our power grids and communications systems. Cottrell’s team examined magnetic minerals that had their magnetism orientated when South Africa’s farmers lit fires between 500 and 1000 years ago.
This captures the size and direction of Earth’s magnetic field. “It fixes the magnetic field at that time,” says Cottrell. The analysis shows that around the year 1370, field strength was falling by 0.054 microteslas a year – substantially faster than today’s drop of 0.036 microteslas (Nature Communications, DOI: 10.1038/ncomms8865). Until now, we’d had a poor record of magnetic field changes in the southern hemisphere.
THE eyes may be windows to the mind, but for children with autism, the body is the better communicator. They are just as good at reading emotions in body language as those without autism. The finding challenges the idea that children with autism have difficulty reading emotions. This may have arisen from studies focusing on whether children can read emotions from just the face or eyes, says Candida Peterson at the University of Queensland in Australia. “Autistic people don’t like making eye contact,” she says, as this requires a close encounter with someone. Reading body language can be done from afar. In the study, children aged 5 to 12 were shown photos of adults with blurred faces posing in ways to convey six emotions. Those with autism were just as good as those without at recognising the emotions (Journal of Experimental Child Psychology, doi.org/6dp).
Drug resistance builds better bugs RESISTANCE doesn’t just allow bacteria to evade drugs – it also makes them stronger. The finding challenges the dogma that drug resistance comes at a cost to the bacterium. David Skurnik at Harvard Medical School in Boston exposed healthy mice to various strains of bacteria, some with antibiotic resistance. These were better at surviving than the non-resistant ones (Science Translational Medicine, doi.org/6ds). Most efforts to tackle resistance have focused on minimising the use of antibiotics, the idea being that this would give non-resistant bacteria the chance to outcompete their supposedly weaker counterparts. Skurnik’s work suggests it won’t be this easy.
in Brief Autistic kids can read body language
Droplets of oil turn human cells into living lasers INDIVIDUAL cells have been made to act like tiny lasers, allowing them to be monitored more accurately. Making cells shoot laser beams may sound fantastical, says Matjaž Humar of Harvard Medical School in Cambridge, Massachusetts, but the techniques are surprisingly straightforward. “It’s actually super-easy.” Humar and his colleagues developed three ways to get cells to emit visible light. The first involved injecting each one with a tiny oil droplet – this formed an optical cavity in the cell that could be filled with fluorescent dye. When a light pulse was shone onto the cavity, the dye atoms
entered an excited state, emitting light. In a less invasive procedure, polystyrene beads were scattered in a Petri dish filled with macrophages, a type of white blood cell that ingests foreign material – such as the beads. Once ingested, the 10-micrometre-wide beads performed the same function as the oil droplets, acting as an optical cavity capable of emitting highly focused laser light. The final mechanism involved exploiting the fatty droplets already found within living cells (the yellow spheres above). “We all have these fat cells inside our tissue. We are all made of lasers,” says Humar (Nature Photonics, DOI: 10.1038/nphoton.2015.129). The technology could be used to monitor the spread of tumour cells or the behaviour of immune cells.
Earth’s magnetic pole may not flip soon FLIPPING heck! Deposits from fires set by farmers centuries ago reveal that Earth’s magnetic field dramatically weakened in the past without actually flipping – suggesting that current field weakening might not necessarily lead to a pole swap either. Earth’s poles have swapped in the past, but without a regular pattern, says Rory Cottrell of the University of Rochester in New 14 | NewScientist | 1 August 2015
York. This means we don’t know when they will flip again – but many suspect it might be soon: the field has been weakening since about 1840. A flip may affect our power grids and communications systems. Cottrell’s team examined magnetic minerals that had their magnetism orientated when South Africa’s farmers lit fires between 500 and 1000 years ago.
This captures the size and direction of Earth’s magnetic field. “It fixes the magnetic field at that time,” says Cottrell. The analysis shows that around the year 1370, field strength was falling by 0.054 microteslas a year – substantially faster than today’s drop of 0.036 microteslas (Nature Communications, DOI: 10.1038/ncomms8865). Until now, we’d had a poor record of magnetic field changes in the southern hemisphere.
THE eyes may be windows to the mind, but for children with autism, the body is the better communicator. They are just as good at reading emotions in body language as those without autism. The finding challenges the idea that children with autism have difficulty reading emotions. This may have arisen from studies focusing on whether children can read emotions from just the face or eyes, says Candida Peterson at the University of Queensland in Australia. “Autistic people don’t like making eye contact,” she says, as this requires a close encounter with someone. Reading body language can be done from afar. In the study, children aged 5 to 12 were shown photos of adults with blurred faces posing in ways to convey six emotions. Those with autism were just as good as those without at recognising the emotions (Journal of Experimental Child Psychology, doi.org/6dp).
Drug resistance builds better bugs RESISTANCE doesn’t just allow bacteria to evade drugs – it also makes them stronger. The finding challenges the dogma that drug resistance comes at a cost to the bacterium. David Skurnik at Harvard Medical School in Boston exposed healthy mice to various strains of bacteria, some with antibiotic resistance. These were better at surviving than the non-resistant ones (Science Translational Medicine, doi.org/6ds). Most efforts to tackle resistance have focused on minimising the use of antibiotics, the idea being that this would give non-resistant bacteria the chance to outcompete their supposedly weaker counterparts. Skurnik’s work suggests it won’t be this easy.