(Funded by the U.S. National Science Foundation)
Researchers from the Singapore-Massachusetts Institute of Technology (MIT) Alliance for Research and Technology in Singapore, in collaboration with Temasek Life Sciences Laboratory (TLL) and MIT, have developed a groundbreaking near-infrared fluorescent nanosensor that can simultaneously detect and differentiate between iron (II) and iron (III) in living plants. This first-of-its-kind nanosensor allows precise localization of iron in plant tissues or subcellular compartments, enabling the measurement of even minute changes in iron levels within plants. The nanosensor features single-walled carbon nanotubes wrapped in a negatively charged fluorescent polymer, forming a structure that interacts differently with iron (II) and iron (III).

(Funded by the U.S. Department of Defense and the U.S. National Science Foundation)
Researchers from Cornell University and the Army Research Laboratory have devised a new method for designing metals and alloys that can withstand extreme impacts. When a metallic material is struck at an extremely high speed, it immediately ruptures and fails. The reason for that failure is embrittlement – the material loses its ability to bend without breaking – when deformed rapidly. The researchers created a nanocrystalline alloy made of copper and tantalum in which dislocations could barely move more than a few nanometers before they were stopped in their tracks, effectively suppressing embrittlement. Dislocations are tiny defects that move through a crystal. During rapid, extreme strains, the dislocations accelerate and interact with lattice vibrations, which create substantial resistance that leads to embrittlement.

(Funded by the U.S. Department of Energy and the U.S. National Science Foundation)
Researchers from the U.S. Department of Energy’s (DOE) Oak Ridge National Laboratory (ORNL), Purdue University, and the University of Illinois Urbana−Champaign have used a nanoscale quantum sensor to measure spin fluctuations near a phase transition in a magnetic thin film. Thin films with magnetic properties at room temperature are essential for data storage, sensors and electronic devices because their magnetic properties can be precisely controlled and manipulated. The researchers used a specialized instrument called a scanning nitrogen-vacancy center microscope at the Center for Nanophase Materials Sciences, a DOE Office of Science user facility at ORNL. A nitrogen-vacancy center is an atomic-scale defect in diamond in which a nitrogen atom takes the place of a carbon atom, and a neighboring carbon atom is missing, creating a special configuration of quantum spin states.

(Funded by the U.S. National Science Foundation)
Scientists have blended electron microscopy with artificial intelligence (AI) so they can observe the movements of atoms in nanoparticles at an unprecedented time resolution. Because the atoms are usually barely visible in electron microscope images, scientists cannot be sure how they are behaving. So, the scientists in this study trained a deep neural network, AI’s computational engine, that can “light up” the electron-microscope images, revealing the underlying atoms and their dynamic behaviors. “We have developed an artificial-intelligence method that opens a new window for the exploration of atomic-level structural dynamics in materials,” says Carlos Fernandez-Granda, one of the scientists involved in this study.

(Funded by the U.S. National Science Foundation)
Researchers at Northwestern University have created a new platform for monitoring chemical contaminants in the environment. The platform can detect the metals lead and cadmium at concentrations down to two and one parts per billion, respectively, in a matter of minutes. It was created by interfacing nanomechanical microcantilevers with synthetic biology biosensors. When the tiny cantilevers are coated with DNA molecules, biosensing molecules bind to the DNA, causing the cantilevers to bend. When exposed to toxic metals, the biosensors unbind, causing the cantilever to “de-bend,” which can be measured precisely to detect the toxic metals.