First 3-D heart printed using multiple imaging techniques

GRAND RAPIDS, MI — Congenital heart experts from Spectrum Health Helen DeVos Children’s Hospital have successfully integrated two common imaging techniques to produce a three-dimensional anatomic model of a patient’s heart. The 3-D model printing of patients’ hearts has become more common in recent years as part of an emerging, experimental field devoted to enhanced visualization of individual cardiac structures and characteristics. But this is the first time the integration of computed tomography (CT) and three-dimensional transesophageal echocardiography (3DTEE) has successfully been used for printing a hybrid 3-D model of a patient’s heart. A proof-of-concept study authored by the Spectrum Health experts also opens the way for these techniques to be used in combination with a third tool — magnetic resonance imaging (MRI).

“Hybrid 3D printing integrates the best aspects of two or more imaging modalities, which can potentially enhance diagnosis, as well as interventional and surgical planning," said Jordan Gosnell, Helen DeVos Children’s Hospital cardiac sonographer, and lead author of the study. “Previous methods of 3D printing utilize only one imaging modality, which may not be as accurate as merging two or more datasets.”

Seahorse tails could inspire new generation of robots

Inspiration for the next big technological breakthrough in robotics, defense systems and biomedicine could come from a seahorse’s tail, according to a new study reported in Science.

The research centers on the curious shape of seahorse tails and was led by Clemson Univ.’s Michael M. Porter, an assistant professor of mechanical engineering.

Seahorse tails are organized into square prisms surrounded by bony plates that are connected by joints. Many other creatures, ranging from New World monkeys to rodents, have cylindrical tails.

Researchers wanted to know whether the square-prism shape gives seahorse tails a functional advantage.

To find out, the team created a 3D-printed model that mimicked the square prism of a seahorse tail and a hypothetical version that was cylindrical. Then researchers whacked the models with a rubber mallet and twisted and bent them.

Researchers found that the square prototype was stiffer, stronger and more resilient than the circular one when crushed. The square prototype was about half as able to twist, a restriction that could prevent damage to the seahorse and give it better control when it grabs things.

Both prototypes could bend about 90 degrees, although the cylindrical version was slightly less restricted.

Bioprinted “play dough” capable of cell and protein transfer

Scientists have developed a new technique allowing the bioprinting at ambient temperatures of a strong paste similar to play dough capable of incorporating protein-releasing microspheres.

The scientists demonstrated that the bioprinted material, in the form of a microparticle paste capable of being injected via a syringe, could sustain stresses and strains similar to cancellous bone—the “spongy” bone tissue typically found at the end of long bones.

This work, published in Biofabrication, suggests bioprinting at ambient temperatures is a viable route to the production of materials for bone repair which would allow the inclusion of cells and proteins capable of accelerating the healing of large fractures.

"Bioprinting is a hot research area in tissue engineering," explains Dr. Jing Yang, of the Univ. of Nottingham, a lead author on the paper. "However it usually requires a printing environment that isn't compatible with living cells—and those materials that are compatible with living cells usually don't have sufficient mechanical properties for certain applications."

Autonomous taxis would deliver significant environmental, economic benefits

Imagine a fleet of driverless taxis roaming your city, ready to pick you up and take you to your destination at a moment’s notice. While this may seem fantastical, it may be only a matter of time before it becomes reality. And according to a new study from Lawrence Berkeley National Laboratory (Berkeley Lab), such a system would both be cost-effective and greatly reduce per-mile emissions of greenhouse gases.

The analysis found that the per-mile greenhouse gas emissions of an electric vehicle deployed as a self-driving, or autonomous, taxi in 2030 would be 63 to 82% lower than a projected 2030 hybrid vehicle driven as a privately owned car and 90% lower than a 2014 gasoline-powered private vehicle. Almost half of the savings is attributable to “right-sizing,” where the size of the taxi deployed is tailored to each trip’s occupancy needs.

The results were published online by Nature Climate Change in an article co-authored by Berkeley Lab scientists Jeffery Greenblatt and Samveg Saxena.

“When we first started looking at autonomous vehicles, we found that, of all the variables we could consider, the use of autonomous vehicles as part of a shared transit system seemed to be the biggest lever that pointed to lower energy use per mile,” said Greenblatt.

A jump for soft-bodied robots

Traditional robots are made of components and rigid materials like you might see on an automotive assembly line—metal and hydraulic parts, harshly rigid and extremely strong. But away from the assembly line, for robots to harmoniously assist humans in close–range tasks scientists are designing new classes of soft–bodied robots. Yet one of the challenges is integrating soft materials with requisite rigid components that power and control the robot's body. At the interface of these materials, stresses concentrate and structural integrity can be compromised, which often results in mechanical failure.

But now, by understanding how organisms solve this problem by self–assembling their bodies in a way that produces a gradual transitioning from hard to soft parts, a team of Wyss Institute researchers and their collaborators have been able to use a novel 3-D printing strategy to construct entire robots in a single build that incorporate this biodesign principle. The strategy permits construction of highly complex and robust structures that can't be achieved using conventional nuts and bolts manufacturing. A proof–of–concept prototype—a soft–bodied autonomous jumping robot reported in Science—was 3-D printed layer upon layer to ease the transition from its rigid core components to a soft outer exterior using a series of nine sequential material gradients.