Changing the fate of stem cells

Researchers at the Wyss Institute for Biologically Inspired Engineering at Harvard Univ. and the Harvard John A. Paulson School of Engineering and Applied Sciences (SEAS) have developed a new, more precise way to synthetically control differentiation of stem cells into bone cells by leveraging bioinspired hydrogels. This new technique has promising applications in the realm of bone regeneration, growth and healing. The research led by David Mooney, PhD, Wyss Institute Core Faculty member and Robert P. Pinkas Family Professor of Bioengineering at SEAS, was published in Nature Materials.

The extracellular matrix, a microenvironment of proteins and polymers that surrounds and connects cells, impacts a range of cellular behaviors including differentiation. For about a decade, researchers have been able to direct the fate of stem cells by tuning the mechanical stiffness of synthetic microenvironments such as hydrogels. Stem cells in more flexible hydrogels have been shown to differentiate into fat cells while those in stiffer hydrogels are more likely to differentiate into osteogenic (bone) cells.

Jaguar Land Rover Introduces Holographic Head-up Display

In 1988, General Motors brought the first head-up display (HUD) to market. Designed with the intent to keep driver attention on the road, these systems display vital information, such as vehicle speed and warning messages, in the driver’s field of vision.

Today, this technology is widely available, but the Univ. of Cambridge and Jaguar have teamed up to offer the first HUD to use laser holographic techniques to project information.

“We’re moving towards a fully immersive driver experience in cars, and we think holographic technology could be a big part of that, by providing important information, or even by encouraging good driver behavior,” said Prof. Daping Chu, of the university’s Dept. of Engineering and the Chairman of the Centre for Advanced Photonics and Electronics (CAPE).

Living Ant Bridges Have Implications for Robotics

Imagine this scenario: An earthquake strikes, collapsing the ends of a crowded bridge. People are stranded on the bridge’s interior, the gap to land being too big to jump. Emergency crews dispatch, but discover upon arrival that any sort of human intervention borders on fatal. Instead, the crews send out an array of insect-like robots. The robots coalesce, forming a platform where the gap once was. The trapped people cross safely to land.

While the above scenario is hypothetical, researchers have discovered army ants, known for building living bridges by linking their bodies, are capable of moving their bridges from the original building points to cover larger swaths.

Microscopic Water Bears Incorporate Foreign DNA into Genome

From the peaks of the Himalayas and the ocean’s deepest depths to frigid Antarctica and the searing deserts, tardigrades are animals that thrive in extremes.

Dry them out, and tardigrades can survive for years, even decades. Add water, and they spring back to life, raring to reproduce, feed and live their normal lives. Radiation? Not a problem, these microscopic animals can survive doses thousands of times more intense than humans can. The vacuum of space? Yeah, they survived that too.

“These abilities to survive these extreme stresses is what really got me interested in studying tardigrades,” says Thomas Boothby, a postdoctoral fellow at the Univ. of North Carolina at Chapel Hill, in an interview with R&D Magazine.  

Boothby and Bob Goldstein, a faculty member of UNC’s College of Arts and Sciences, recently sequenced the genome of these microscopic cosmopolitans. Surprisingly, the discovered 17.5% of their genome, around 6,000 genes, are from foreign DNA.

Launching into the Aurora Borealis

A psychedelic array, the aurora borealis are shimmering lights resulting from electrons form the sun colliding with particles in the Earth’s atmosphere. Against an ocean of stars, the phenomenon almost appears as cloudy drops of paint dispersing through water.

NASA, this winter, will launch two sounding rockets through the Northern Lights in Norway to study what is known as a cusp aurora, when “energetic particles are accelerated downward into the atmosphere directly from the solar wind—that is, the constant outward flow of solar material from the sun,” according to NASA. Cusp auroras, though not rare, pose a problem for visibility, as they often occur during daylight hours.

However, “the magnetic pole is tilted towards North America, putting this magnetic opening—the cusp—at a higher latitude on the European side,” said Jim LaBelle, principal investigator of the CAPER (Cusp Alfven and Plasma Electrodynamics Rocket) sounding rocket, one of the two rockets slated for launch. “Combine that extra-high latitude with the winter solstice—when nights are longest, especially as you go farther north—and you can sometimes see this daytime aurora with the naked eye.”

Tiny, ultracool star is super stormy

Our sun is a relatively quiet star that only occasionally releases solar flares or blasts of energetic particles that threaten satellites and power grids. You might think that smaller, cooler stars would be even more sedate. However, astronomers have now identified a tiny star with a monstrous temper. It shows evidence of much stronger flares than anything our sun produces. If similar stars prove to be just as stormy, then potentially habitable planets orbiting them are likely to be much less hospitable than previously thought.

"If we lived around a star like this one, we wouldn't have any satellite communications. In fact, it might be extremely difficult for life to evolve at all in such a stormy environment," says lead author Peter Williams of the Harvard-Smithsonian Center for Astrophysics (CfA).

An eagle-eye, real-time view of neural activity

Researchers at Duke and Stanford Univs. have devised a way to watch the details of neurons at work, pretty much in real time.

Every second of every day, the 100 billion neurons in your brain are capable of firing off a burst of electricity called an action potential up to 100 times per second. For neurologists trying to study how this overwhelming amount of activity across an entire brain translates into specific thoughts and behaviors, they need a faster way to watch.

Existing techniques for monitoring neurons are too slow or too tightly focused to generate a holistic view. But in a new study, researchers reveal a technique for watching the brain's neurons in action with a time resolution of about 0.2 usec—a speed just fast enough to capture the action potentials in mammalian brains.

The paper appeared early online in Science.

"We set out to combine a protein that can quickly sense neural voltage potentials with another protein that can amplify its signal output," said Yiyang Gong, assistant professor of biomedical engineering at Duke and first author on the paper. "The resulting increase in sensor speed matches what is needed to read out electrical spikes in the brains of live animals."