Imperfections in the regular atomic arrangements in crystals determine many of the properties of a material, and their diffusion is behind many microstructural changes in solids. However, imaging non-repeating atomic arrangements is difficult in conventional materials. Now, researchers in Austria have directly imaged the diffusion of a butterfly-shaped atomic defect in graphene.
In a new study, researchers show for the first time how the brain rewires and fine-tunes its connections differently depending on the relative timing of sensory stimuli. This marks the first time that direct, real-time evidence from watching brain cells in an intact animal has been used to support a 65-year-old model of how nerve circuits refine their connectivity.
Batteries don’t age gracefully. The lithium ions that power portable electronics cause lingering structural damage with each cycle of charge and discharge, making devices from smartphones to tablets tick toward zero faster and faster over time. To stop or slow this steady degradation, scientists must track and tweak the imperfect chemistry of lithium-ion batteries with nanoscale precision.
In order to see the true polarization of ferroelectric materials quickly and efficiently, researchers at Argonne National Laboratory have developed a new technique called charge gradient microscopy. Charge gradient microscopy uses the tip of a conventional atomic force microscope to scrape and collect the surface screen charges.
In recent research in Germany, the desorption of oxygen molecules from a silver surface was successfully visualized for the first time using low-energy electron microscopy. The effects account for the shortcomings of conventional models of desorption, which often deliver rates that do not agree with experimentally determined values.
Biologists and doctors rely heavily on incubators and microscopes. Researchers have invented a new type of microscope that combines the functions of both these tools in a compact system. The incubator microscope is ideally suited for time-lapse examination over a number of weeks and for automatic observation of cell cultures. No bigger than a soda can, it costs 30 times less than buying an incubator and a microscope separately.
In response to requests from the semiconductor industry, a team of researchers at the Physical Measurement Laboratory has demonstrated that atomic force microscope probe tips made from its near-perfect gallium nitride nanowires are superior in many respects to standard silicon or platinum tips. They also found a way to use the tips as LEDs to illuminate sample regions while scanning.
A pathway to the design of even more effective versions of the powerful anticancer drug Taxol has been opened with the most detailed look ever at the assembly and disassembly of microtubules, tiny fibers of tubulin protein that form the cytoskeletons of living cells and play a crucial role in mitosis.
Crowding has notoriously negative effects at large size scales, blamed for everything from human disease and depression to community resource shortages. But relatively little is known about the influence of crowding at the cellular level. A new JILA study shows that a crowded environment has dramatic effects on individual biomolecules.
Researchers at Massachusetts Institute of Technology and the Univ. of Vienna have created an imaging system that reveals neural activity throughout the brains of living animals. This technique, the first that can generate 3-D movies of entire brains at the millisecond timescale, could help scientists discover how neuronal networks process sensory information and generate behavior.
Univ. of Utah researchers devised a way to watch newly forming AIDS virus particles emerging or “budding” from infected human cells without interfering with the process. The method shows a protein named ALIX gets involved during the final stages of virus replication, not earlier, as was believed previously.
Researchers at the National Physical Laboratory and the London Centre for Nanotechnology have determined the structure of DNA from measurements on a single molecule using atomic force microscopy (AFM), and found significant variations in the well-known double helix.
In new work, a research team has shed light on a type of molecular motor used to package the DNA of a number of viruses, including such human pathogens as herpes and the adenoviruses. The scientists found that this viral packaging motor exerts torque to rotate DNA and adapts to changing conditions in order to coordinate its mechano-chemical activity.
A research collaboration has combined several experimental and computational methods to measure, for the first time, the energy needed to change the magnetic anisotropy of a single cobalt atom. Their methodology included the use of inelastic electron tunneling spectroscopy to determine a cobalt atom’s “stubbornness”, or preference toward specific magnetic direction.
Researchers at NIST have recently built the first low-energy focused ion beam (FIB) microscope that uses a lithium ion source. Although the new microscope's resolution isn't yet as good as a scanning electron microscope or a helium ion microscope (HIM), it can image nonconductive materials and can more clearly visualize the chemical composition on the surface of a sample than the higher-energy SEMs and FIBs.
Super-resolution microscopy has allowed optical imaging of objects with dimensions smaller than the diffraction limit. Researchers studying a type of material called supramolecular polymers have used this type of imaging to develop a new technique that allows them study molecular self-assembly at an unprecedented level of detail.
An interdisciplinary team of scientists in Belgium has developed a new technique to examine how proteins interact with each other at the level of a single HIV viral particle. The technique allows scientists to study the life-threatening virus in detail and makes screening potential anti-HIV drugs quicker and more efficient. The technique can also be used to study other diseases.
In 2010 Lawrence Livermore National Laboratory introduced a new type of electron microscope that could study structural dynamics in condensed matter with the help of a nanosecond laser “pump” that could capture images. In 2013, the laboratory won another R&D 100 Award for speeding up this process more than 100,000 times, resulting in a “movie-mode” version of the instrument.
Researchers in the U.K. have applied “soft-touch” atomic force microscopy to large, irregularly arranged and individual DNA molecules. In this form of microscopy, a miniature probe is used to feel the surface of the molecules one by one, rather than seeing them. In this way they have determined the structure of DNA from measurements on a single molecule, and found that the structure is more irregular than previously thought.
A team of scientists, led by physicist Amir Yacoby of Harvard Univ., has developed a magnetic resonance imaging (MRI) system that can produce nanoscale images, and may one day allow researchers to peer into the atomic structure of individual molecules. Though not yet precise enough to capture atomic-scale images of a single molecule, the system already has been used to capture images of single electron spins.
A research group in Japan has developed a new advanced system that combines a super-resolution microscope and a deposition chamber for growing oxide thin films. With this system, they successfully observed for the first time the growing of metal-oxide thin films at an atomic level on the surface of single-crystal strontium titanate.
A quasiparticle called an exciton has been understood theoretically for decades. But exciton movement within materials has never been directly observed. Now scientists have achieved that feat, imaging excitons’ motions directly. This could enable research leading to significant advances in electronics, they say, as well as a better understanding of natural energy-transfer processes, such as photosynthesis.
Biological samples bend light in unpredictable ways, returning difficult-to-interpret information to the microscope. Using a form of adaptive optics, Janelia Farm Research Campus scientists have developed a microscopy technique that can rapidly correct for distortions and sharpen high-resolution images over large volumes of tissue.
Recent experiments in Austria have explained the behavior of electrons at tiny step edges on titanium oxide surfaces. The finding, which shows why oxygen atoms attach so well to these edges, is important for solar cell technology and novel, more effective catalysts.
Researchers at JILA in Colorado have engineered a short, flexible, reusable probe for the atomic force microscope (AFM) that enables state-of-the-art precision and stability in picoscale force measurements. Shorter, softer and more agile than standard and recently enhanced AFM probes, the JILA tips will benefit nanotechnology and studies of folding and stretching in biomolecules such as proteins and DNA.