Microscopy

‘Leap forward’ in risk management of rectal cancer

Rectal cancer, along with colon cancer, is the third-most common type of cancer in the United States, and treatment and surgery greatly affect the quality of life of patients. A multi-disciplinary team at Washington University in St. Louis has developed and tested an innovative imaging technique that is able to differentiate between rectal tissues with residual cancers and those without tumors after chemotherapy and radiation, which could one day help to avoid unnecessary surgeries in some patients who have achieved complete tumor destruction after chemoradiation.

UCI scientists measure local vibrational modes at individual crystalline faults

Irvine, Calif., Jan. 11, 2021 – Often admired for their flawless appearance to the naked eye, crystals can have defects at the nanometer scale, and these imperfections may affect the thermal and heat transport properties of crystalline materials used in a variety of high-technology devices. Employing newly developed electron microscopy techniques, researchers at the University of California, Irvine and other institutions have, for the first time, measured the spectra of phonons – quantum mechanical vibrations in a lattice – at individual crystalline faults, and they discovered the propagation of phonons near the flaws.

Defects Slow the Electron’s Dance

Researchers used two advanced microscopy techniques to learn how crystal defects affect the performance of crystalline solar cells called lead halide perovskite cells. The research used two microscopy techniques: electron backscattering diffraction to view crystal quality at scales of 100 nanometers and ultrafast microscopy to examine how electrons move. The research shows that microscopic defects that form when the crystals are made can reduce how fast electrons move by a factor of almost 10.

October 27, 2020 Web Feature Enabling the Data-Driven Future of Microscopy

An international research team led by PNNL has published a vision for electron microscopy infused with the latest advances in data science and artificial intelligence. Writing a commentary in Nature Materials, the team proposes a highly integrated, autonomous, and data-driven microscopy architecture to address challenges in energy storage, quantum information science, and materials design.

UCI materials scientists discover design secrets of nearly indestructible insect

Irvine, Calif., Oct. 21, 2020 – With one of the more awe-inspiring names in the animal kingdom, the diabolical ironclad beetle is one formidable insect. Birds, lizards and rodents frequently try to make a meal of it but seldom succeed. Run over it with a car, and the critter lives on. The beetle’s survival depends on two key factors: its ability to convincingly play dead and an exoskeleton that’s one of the toughest, most crush-resistant structures known to exist in the biological world.

Study First to Tally Biomass from Oceanic Plastic Debris Using Visualization Method

Scientists examined cell abundances, size, cellular carbon mass, and how photosynthetic cells differ on polymeric and glass substrates over time, exploring nanoparticle generation from plastic like polystyrene and how this might disrupt microalgae. Conservative estimates suggest that about 1 percent of microbial cells in the ocean surface microlayer inhabit plastic debris globally. This mass of cells would not exist without plastic debris in the ocean, and thus, represents a disruption of the proportions of native flora in that habitat.

UCI materials scientists study a sea creature that packs a powerful punch

Irvine, Calif., Aug. 17, 2020 – University of California, Irvine materials scientists are learning about resilience from the mantis shrimp. The ancient crustaceans are armed with two hammerlike raptorial appendages called dactyl clubs that they use to bludgeon and smash their prey. These fists, able to accelerate from the body at over 50 mph, deliver powerful blows yet appear undamaged afterward.

Pioneering method reveals dynamic structure in HIV

The method reveals that the lattice, which forms the major structural component of the human immunodeficiency virus (HIV), is dynamic. The discovery of a diffusing lattice made from Gag and GagPol proteins, long considered to be completely static, opens up potential new therapies. The method can be applied to biomedical structure.

Good vibrations show how water works

Researchers demonstrated new ways to use electron microscopy to study liquids at high resolution. They used this technique to examine how nuclei in liquids and molecules vibrate at multiple length scales. This work can lead to new ways for scientists to describe liquids, the interfaces between fluids, and materials labeled with isotopes.

Advanced microscopy reveals unusual DNA structure

An advanced imaging technique reveals new structural details of S-DNA, ladder-like DNA that forms when the molecule experiences extreme tension. This work conducted at Sandia National Laboratories and Vrije University in the Netherlands provides the first experimental evidence that S-DNA contains highly tilted base pairs.

UCI scientists reveal mechanism of electron charge exchange in molecules

Irvine, Calif., Oct. 14, 2019 – Researchers at the University of California, Irvine have developed a new scanning transmission electron microscopy method that enables visualization of the electric charge density of materials at sub-angstrom resolution. With this technique, the UCI scientists were able to observe electron distribution between atoms and molecules and uncover clues to the origins of ferroelectricity, the capacity of certain crystals to possess spontaneous electric polarization that can be switched by the application of an electric field.