News from the NNI Community - Research Advances Funded by Agencies Participating in the NNI

Researchers at the University of Pennsylvania have investigated how neutrophils – the white blood cells responsible for detecting and eliminating harmful particles in the body – are able to differentiate between bacteria and other compounds in the bloodstream, such as cholesterol particles. They tested a library consisting of 23 different protein-based nanoparticles, which revealed a set of "rules" that predict uptake by neutrophils. Neutrophils don't take up symmetrical, rigid particles, such as viruses, but they take up nanoparticles that exhibit "protein clumping." 

Researchers at Northwestern University and the Toyota Research Institute have successfully applied machine learning to guide the synthesis of new nanomaterials. The highly trained algorithm combed through a defined dataset to accurately predict new structures that could fuel processes in clean energy and in chemical and automotive industries.

Researchers at Rice University have calculated how strains and stresses affect both individual nanotubes and those assembled into fibers. They found that while nanotube fibers can fail under cyclic loads over time, nanotubes may remain perfect. The researchers hope to give other researchers and industry a way to predict how long nanotube fibers and other assemblies can be expected to last under given conditions.

Physicists at the University of Nebraska–Lincoln have shown that antiferromagnets can be used to store and process data in a way that would complement the digital electronics that are currently used in cell phones and computers. Antiferromagnets are a type of material that generate virtually no net magnetic field. In contrast, most spintronic memory components so far have relied on ferromagnets – materials with a permanent magnetic field. This discovery reveals that similar to ferromagnets, antiferrromagnets could be used to make nanometer-scale components of computer storage devices, and such devices would store and process data much faster than current storage devices.

Researchers at the U.S. Department of Energy’s Lawrence Berkeley National Laboratory and the University of California, Berkeley, have developed a method to stabilize the edges of graphene nanoribbons and directly measure their unique magnetic properties. The researchers found that by substituting some of the carbon atoms along the ribbon's zigzag edges with nitrogen atoms, they could discretely tune the local electronic structure without disrupting the magnetic properties. 

Researchers at The Ohio State University have shown that atomic-scale magnetic patterns looking like a hedgehog's spikes could enable the future development of hard disks with massively larger capacities than today's devices. The researchers used a scanning tunneling microscope, which provided pictures of the magnetic patterns with atomic resolution. The images revealed that the "body" of the hedgehog was only 10 nanometers wide, which is smaller than today's magnetic bits (about 50 nanometers). This finding could help data centers keep up with the exponentially increasing demand for video and cloud data storage.

Researchers at the University of Pennsylvania, Pennsylvania State University, the University of California at Los Angeles, the University of Dayton, the U.S. Department of Energy’s Brookhaven National Laboratory, the Air Force Research Laboratory, and AIXTRON Ltd in Cambridge, United Kingdom, have developed a new method of manufacturing atomically thin (five-atoms thick) superlattices – semiconductor films that detect and emit light. One-atom-thick materials generally take the form of a lattice, or a layer of geometrically aligned atoms that form a pattern specific to each material. A superlattice is made up of lattices of different materials stacked upon one another and has completely new optical, chemical, and physical properties.

Researchers at Wake Forest School of Medicine have discovered that a nanoparticle therapeutic enhances cancer immunotherapy and is a possible new approach in treating malignant pleural effusion (MPE). MPE is the accumulation of fluid between the chest wall and lungs and is accompanied by malignant cells and/or tumors. Clinical evidence suggests that MPE comprises abundant tumor-associated immune cells that prevent the body’s immune system from recognizing and eliminating the cancer. To mitigate this issue, the researchers developed a nanoparticle called liposomal cyclic dinucleotide for targeted activation of an immune pathway that reprograms tumor-associated immune cells to active anti-tumor ones. 

A team of researchers from Harvard University and MIT has observed exotic fractional states at low magnetic field in twisted bilayer graphene for the first time. The researchers were interested in a specific exotic quantum state, known as fractional Chern insulators. Chern insulators conduct electricity on their surface or edge but not in the middle. To build their insulator, the researchers used two sheets of graphene twisted together at the so-called magic angle. 

Researchers at North Carolina State University have demonstrated a new design for thermal actuators that can be used to create rapid movement in soft robotic devices. The researchers layered two materials on top of each other, with silver nanowires in the middle. The two materials have different coefficients of thermal expansion, so they expand at different rates as they heat up. This layered material was then shaped into a design that gives it a default curvature in one direction. When voltage is applied to the silver nanowires, the material heats up, making it bend in the other direction.