Higher brain function stem cells, Groundwater depletion, Skin-like circuitry, and Geckos with wet feet
Santos Franco, Scripps Research Institute
Tom Gleeson, McGill University
John Rogers, University of Illinois
Alyssa Stark, University of Akron
Stem cells for higher brain function identified
Stem cells responsible for generating parts of the brain which perform higher brain functions have been identified by scientists at the Scripps Research Institute and published in the journal Science. Previously it was believed that just one type of stem cell produced all of the outermost layer of the brain, the cerebral cortex. However, Santos Franco and his team found that two distinct stem cell populations generate different layers of the cerebral cortex. The outer layers of the cerebral cortex are notably developed in primates, and particularly expanded in humans. Identifying the stem cell responsible for generating these outer layers could help our understanding of human evolution.
"During the evolution of the human brain there was a preferential expansion of the neurons that connect the two hemispheres, which is responsible for some of our higher brain function, like conciousness and cognition. Our study identified the sub class of neural stem cells that specifically make these types of neurons. We think that understanding more about this particular class of neural stem cell, regardless of species, may provide some insight into what makes our brains uniquely human." - Santos Franco
Global groundwater depletion
A quarter of the world's population are living in areas where groundwater stores are under threat. Publishing in Nature, Tom Gleeson of McGill University analysed flows of water into and out of large underground water stores known as aquifers and found that current human consumption of several large aquifers is exceeding the rate at which they can be refilled.
"What we've shown in that humans are overexploiting groundwater in many large aquifers around the world that are cruical for agriculture. This will have ecological impacts, and it could also impact on the availability of water to grow food and for drinking water. This will impact areas of the world where a quarter of the world's population live." - Tom Gleeson
Skin-like circuitry brings therapy to the fingertips
Silicon based sensors and stimulators that can be applied to the fingertips have been developed by John Rogers at the University of Illinois. The circuits can be used to convey sensory information from the outside of a glove to the skin beneath, making the glove seem mechanically invisible to the wearer. The research, published in the journal Nanotechnology, could lead to the development of improved surgical gloves that will enable surgeons to explore tissues in ways that their fingers alone wouldn't be able to sense...
"One of the interesting potential applications of this technology is in an advanced, instrumented surgical glove, which will allow a doctor, during a surgical procedure to make an electrical assessment of the health status of a tissue, like cardiac muscle, and then perform an intervention to eliminate an abberant region." - John Rogers
Geckos donít like getting their feet wet
And finally, research by Alyssa Stark at the University of Akron shows that geckos' toes lose their stickiness if they get too wet. Geckos are able to stick to dry and damp surfaces while carrying up to twenty times their own body weight, but only if their toes remain dry. Tiny, water-repellent hair-like structures on their toes called setae bind strongly to dry surfaces, but when soaked in water, these hairs are no longer able to do their job.
"We tested the gecko adhesive system in multiple environments. So we tested them first on dry glass, we also tested them on glass that was submerged underwater, and then finally we tested them on glass that had misted water droplets, which is a little bit more similar to what they might experience in their natural environment. And we found that when their toes were wet, they were unable to stick to any of these three treatments. However, when their toes were dry, they actually were able to stick to the misted surface with water droplets on it, and they were able to hold their body weight." - Alyssa Stark
That research was published in The Journal of Experimental Biology, and is helping sicentists to solve the puzzle of how geckos cope with tropical downpours in their natural environment.
Fate-Restricted Neural Progenitors in the Mammalian Cerebral CortexWater balance of global aquifers revealed by groundwater footprintSilicon nanomembranes for fingertip electronics The effect of surface water and wetting on gecko adhesion