UC Science Today

There’s a new wrinkle in the study of brain anatomy. It turns out that the three-dimensional shape of the cerebral cortex – the wrinkled outer layer of the brain that controls many functions of thinking and sensation – strongly correlates with one’s ancestral background. Study author Chun Chieh Fan of the University of California, San Diego, says they’d noticed that different populations had very different brain shapes. So they paired a sophisticated algorithm tool with neuroimaging data.

"When you do this, we realize even though the shape is very different across the ancestral lineage, we cannot find evidence to suggest there is a functional difference based on those brain shapes."

Fan explains that one’s brain anatomy could eventually lead to more personalized medicine approaches for diagnosing and treating brain diseases.

"We can actually predict, what is a normal trajectory, given your genetic background. Anything deviate away from your normal trajectory, there might be a hint suggesting there’s a problem."

Like musicians, songbirds must practice and refine the songs they learn to become consistent performers and, yes, to even impress potential mates. But how birds learn to sing has remained a mystery until a team of researchers led by Hamish Mehaffey of the University of California, San Francisco identified how two well-known brain pathways interact during song learning.

"So we found a mechanism, by which two of the pathways that we knew were really important for song learning, were able to interact and change each other. And were able to show that they changed in an unusual way, but a way that's consistent with what we know about song learning, where effectively, a part of the brain that controls and conducts the song, is able to interact with the part of the brain that is actively, perturbing it and kicking it around, and making it change a little bit, from trial-to-trial."

Mehaffey says that this all happens in a specialized portion of the brain that’s similar to the human basal ganglia. He says the findings could help explain how humans learn complex motor skills such as playing an instrument or driving a car.

"One of the things we've learned is that this part of the brain is also really important for learning new things and adapting over the course of your life."

There’s a new wrinkle in the study of brain anatomy. It turns out that the three-dimensional shape of the cerebral cortex – the wrinkled outer layer of the brain that controls many functions of thinking and sensation – strongly correlates with one’s ancestral background. Study author Chun Chieh Fan of the University of California, San Diego, says they’d noticed that different populations had very different brain shapes. So they paired a sophisticated algorithm tool with neuroimaging data.

"When you do this, we realize even though the shape is very different across the ancestral lineage, we cannot find evidence to suggest there is a functional difference based on those brain shapes."

Fan explains that one’s brain anatomy could eventually lead to more personalized medicine approaches for diagnosing and treating brain diseases.

"We can actually predict, what is a normal trajectory, given your genetic background. Anything deviate away from your normal trajectory, there might be a hint suggesting there’s a problem."

Like musicians, songbirds must practice and refine the songs they learn to become consistent performers and, yes, to even impress potential mates. But how birds learn to sing has remained a mystery until a team of researchers led by Hamish Mehaffey of the University of California, San Francisco identified how two well-known brain pathways interact during song learning.

"So we found a mechanism, by which two of the pathways that we knew were really important for song learning, were able to interact and change each other. And were able to show that they changed in an unusual way, but a way that's consistent with what we know about song learning, where effectively, a part of the brain that controls and conducts the song, is able to interact with the part of the brain that is actively, perturbing it and kicking it around, and making it change a little bit, from trial-to-trial."

Mehaffey says that this all happens in a specialized portion of the brain that’s similar to the human basal ganglia. He says the findings could help explain how humans learn complex motor skills such as playing an instrument or driving a car.

"One of the things we've learned is that this part of the brain is also really important for learning new things and adapting over the course of your life."

For the first time, an international team of engineers led by the University of California, Berkeley has used 3D printing to produce working electrical components, including resistors, inductors, and capacitors. Mechanical engineering professor Liwei Lin says that came with some challenges since current 3D printers cannot print metal parts.

"So what we have done, is actually just do 3D printing of plastic material, together with wax. And then we remove the wax and add these silver particles as our metal. So it’s almost like liquid before you cure it. So you can actually put this one into any shape and cure it with time. The solvent will actually evaporate and then will solidify and has a good property like metal."

They tested the new technology by printing a wireless smart cap that was able to detect spoiled milk using embedded sensors.

"This is the first time we demonstrate a working device like a sensor out of this 3D printing process."

For the first time, an international team of engineers led by the University of California, Berkeley has used 3D printing to produce working electrical components, including resistors, inductors, and capacitors. Mechanical engineering professor Liwei Lin says that came with some challenges since current 3D printers cannot print metal parts.

"So what we have done, is actually just do 3D printing of plastic material, together with wax. And then we remove the wax and add these silver particles as our metal. So it’s almost like liquid before you cure it. So you can actually put this one into any shape and cure it with time. The solvent will actually evaporate and then will solidify and has a good property like metal."

They tested the new technology by printing a wireless smart cap that was able to detect spoiled milk using embedded sensors.

"This is the first time we demonstrate a working device like a sensor out of this 3D printing process."

For the first time, an international team of engineers led by the University of California, Berkeley has used 3D printing to produce working electrical components, including resistors, inductors, and capacitors. Mechanical engineering professor Liwei Lin says that came with some challenges since current 3D printers cannot print metal parts.

"So what we have done, is actually just do 3D printing of plastic material, together with wax. And then we remove the wax and add these silver particles as our metal. So it’s almost like liquid before you cure it. So you can actually put this one into any shape and cure it with time. The solvent will actually evaporate and then will solidify and has a good property like metal."

They tested the new technology by printing a wireless smart cap that was able to detect spoiled milk using embedded sensors.

"This is the first time we demonstrate a working device like a sensor out of this 3D printing process."

Have you ever wondered how scientists date evolutionary events such as when two populations diverged from a common ancestor? Computational biologist Rasmus Nielsen of the University of California, Berkeley says that one method is to use what’s called a molecular clock, which involves counting the mutations in DNA between ancient and living individuals.

"If we take some DNA from you and some DNA from me that DNA will not be identical to each other. It will differ a little bit because there will be mutations that have accumulated in time since we had our most recent common ancestor. Since in the past thousands of years ago, there was some individual that is the ancestor of both of us. By counting mutations, we can figure out something about how long ago since we had our most recent common ancestor. By doing that we can then put dates on these different events, as for example, when did Native Americans start to split up from each other?"

By counting mutations, Nielsen’s team estimated that the first Native Americans split into northern and southern populations around 13,000 years ago.

"And that helped us quite a lot, to distinguish between different hypotheses about how the American continents were peopled."

How do sea urchin embryos develop while defending against so many environmental stressors? To find out, PhD student Lauren Shipp of the University of California, San Diego’s Scripps Institution of Oceanography is using a confocal microscope to generate a 3-D recreation of embryos.

"Sea urchin embryos develop out in the open ocean where they are exposed to a whole variety of chemicals, some of which are naturally occurring and some of which are human generated. And so using this model system to study embryonic development, there is an evolved suite of protective proteins that occur in nature as a result of millions of years of these embryos developing in the face of chemicals. And now with our industrialized society, we are pouring more and more chemicals into the environment that these embryos aren’t used to encountering and so these evolved protective capacities are potentially being overwhelmed. And so this is a good system to study the interaction of those chemicals with the developmental processes of the embryo."

Have you ever wondered how scientists date evolutionary events such as when two populations diverged from a common ancestor? Computational biologist Rasmus Nielsen of the University of California, Berkeley says that one method is to use what’s called a molecular clock, which involves counting the mutations in DNA between ancient and living individuals.

"If we take some DNA from you and some DNA from me that DNA will not be identical to each other. It will differ a little bit because there will be mutations that have accumulated in time since we had our most recent common ancestor. Since in the past thousands of years ago, there was some individual that is the ancestor of both of us. By counting mutations, we can figure out something about how long ago since we had our most recent common ancestor. By doing that we can then put dates on these different events, as for example, when did Native Americans start to split up from each other?"

By counting mutations, Nielsen’s team estimated that the first Native Americans split into northern and southern populations around 13,000 years ago.

"And that helped us quite a lot, to distinguish between different hypotheses about how the American continents were peopled."