Contrast transfer function (CTF) is a vital function in transmission electron microscopy (TEM). It expresses to what extent amplitudes converted from the phase changes of the diffracted waves contribute to the TEM image, including the effects of lens aberrations. Simulation is very helpful to understand the application of the function thoroughly. In this work, we develop the CTFscope as a component in the Landyne software suite, to calculate the CTF with temporal and spatial dumping envelopes for conventional TEM and to extend it to various aberrations (up to fifth order) for aberration-corrected (AC)-TEM. It also includes effects on the CTF and imaging due to the objective aperture and image drift for tutorial purposes. The CTFscope has a user-friendly graphical interface for simulation, visualization, saving, and loading of the microscopy conditions and results. It can be used to explore instrumental performance information due to optical aberrations, effects on the resolution of a TEM and AC-TEM, and for teaching electron microscopy courses.

The Association of Biomolecular Resource Facilities (ABRF) members typically work in cores (shared resources) or in support of them. ABRF's mission is to define excellence for shared resources worldwide. While our vision is to accelerate breakthroughs in scientific discovery, ABRF is committed to advancing the integration of technologies, education, communication, and reproducible research in the operations of shared scientific resources worldwide. Our members support best practices, research excellence, and reproducibility in scientific discovery. ABRF promotes a collaborative community that cultivates professional development and technological innovation. This document outlines a number of things about ABRF, including ABRF's mission and value statements, examples of its research groups and activities, an example of an ABRF outreach program to inform and guide the scientific community about optimization of shared resources nationwide, and an example of an international outreach and collaborative program with like-minded colleagues and organizations in Africa.

The Prospective Instruments MPX-series is a turnkey compact multimodal microscope enabling advanced multiphoton imaging without requiring a laboratory or optical bench. One of the key design features is the ultrafast fiber laser engine integrated into the free moving scan head, which is lightweight, rugged, and allows the ultimate imaging flexibility. A modular design concept allows the user to explore a wide variety of biological applications and measurements, without compromising performance, in any indoor working space. In contrast, standard setups are non-transportable, utility-demanding, and the complexity can be complicated, therefore degrading the value and adding significant initial, short- and long-term expenses. Every clinical and biological researcher should have access to high-quality reliable optical microscopy modalities without being hardware experts. In this article we outline the demand and design of the MPX-microscope and present multiphoton imaging results from experiments in various configurations. There are no existing instruments on the market that are portable and combine easily switchable modes in one composite industry-ready device for life science, clinical, and pharmacological research.

Light-emitting diode (LED) illumination for fluorescence microscopy systems has come a long way since the turn of the century, when the LED sources available had low optical power and a limited range of wavelengths. While the benefits of LED technology were attractive, their limitations prevented large-scale adoption. Twenty years later, advances in the semi-conductor industry have eliminated many of those fundamental hurdles. Today, LED technology is rapidly replacing the lamps used in microscopy and fluorescence imaging, even for applications on the extreme ends of the light microscopy spectrum. This article describes the latest advances in illumination for fluorescence imaging, from near-UV to near-IR fluorophores. Case studies demonstrate the new X-Cite® NOVEM™ as successful replacements for traditional arc lamps in calcium imaging applications, producing equivalent results with the convenience of LEDs. For its usefulness to the microscopy community, the X-Cite NOVEM system was awarded the prestigious 2021 Microscopy Today Innovation Award.

After their crystallization from magmatic melt, minerals such as accessory zircon are often subject to different kinds of chemical impairment. This includes the radiation-induced damage of the crystal lattice due to the incorporation of radioactive elements (U, Th) and the dissolution of the mineral structure due to the permanent action of aggressive fluid phases. Both phenomena can be best studied by using specific crystal sections and electron microscopy visualization techniques (backscattered electron imaging, BSEI). Crystal damage by the emission of α-particles corresponds to a continuous transformation of the regularly structured lattice into an amorphous mass. Mineral dissolution is expressed by the formation of specific corrosion pits, which may be refilled by recrystallized material.

This article introduces the 2D multilayer Laue lens (MLL) nanofocusing optics recently developed for high-resolution hard X-ray microscopy. The new optics utilized a micro-electro-mechanical-system (MEMS)-based template to accommodate two linear MLL optics in a pre-aligned configuration. Angular misalignment between the two lenses was controlled in tens of millidegrees, and the lateral position error was on a micrometer scale. Using the developed 2D MLLs, an astigmatism-free point focus of approximately 14 nm by 13 nm in horizontal and vertical directions, respectively, at 13.6 keV photon energy was obtained. The success of 2D MLL optics with an approaching 10 nm resolution is a significant step forward for the development of high-resolution hard X-ray microscopy and applications of MLL optics in the hard X-ray community.

Low-Z nanocrystalline diamond (NCD) grids have been developed to reduce spurious fluorescence and avoid X-ray peak overlaps or interferences between the specimen and conventional metal grids. The low-Z NCD grids are non-toxic and safe to handle, conductive, can be subjected to high-temperature heating experiments, and may be used for analytical work in lieu of metal grids. Both a half-grid geometry, which can be used for any lift-out method, or a full-grid geometry that can be used for ex situ lift-out or thin film analyses, can be fabricated and used for experiments.

Certain bacteria degrade wood by creating tunnels in cell walls. Transmission electron microscopy (TEM) has played a key role in understanding the intricate architecture of the tunnels produced within the cell wall and the process of cell wall degradation. The most prominent feature of tunnels is the presence of periodic crescent-shaped slime bands, which is the single most important diagnostic characteristic of bacterial tunneling-type cell wall degradation. The review presented covers the aspects relevant to understanding bacterial tunneling of wood cell walls, emphasizing the importance of the application of TEM in this area of research.

Dimetrodon sp. femur, jaw, teeth, and rib bones were collected at N.E. Frederick, OK, and sectioned for histological examination. This Oklahoma Museum of Natural History site has yielded well-preserved Paleozoic fossils for decades. All bones were heavily infiltrated with calcite and other minerals, yet a reddish-brown mass obstructed many vascular channels. This reddish-brown mass reacted to 374 nm UV illumination by emitting bright blue autofluorescence. This was true for every specimen and indicates a heavy presence of iron. We conclude that the iron in the canals is the crystallized remains of blood that clotted during an asphyxiation event that killed the animal. Remarkably similar reddish-brown obstructive material has also been observed in other histological studies performed on Dimetrodon bones. We conclude that these are also the remains of blood clots and simply await examination under UV fluorescence.

The interaction of the electron beam with materials during TEM/STEM imaging often leads to radiation damage. While a variety of low-dose techniques can help mitigate beam damage, true dose management starts with knowing the precise total accumulated dose and dose rate that a sample has seen throughout an experiment. AXON Dose allows users to calibrate their instruments, track electron dose/dose rate across a sample as a function of time and location, and quantify the impact of dose on individual samples.

Theropod dinosaurs have captured the imagination of the public and paleontologists alike. Histology of the bones of theropods has revealed much about dinosaur physiology, behavior, and growth. Histology and ultraviolet fluorescence (UVFL) microscopy of one controversial dinosaur, Nanotyrannus lancensis, reveals the presence of blood clots in post-fixed vessel canals of claw, vertebra, and other isolated post-cranial elements collected at Hell Creek, MT. These clots are thicker, more closely adherent to canal walls, and more reactive to 347 nm UVFL incident light than unfixed specimens. Theropod histology images in the literature display similar clots, and those should be subjected to UVFL for confirmation. In addition, nematodes are evidently preserved in vessel canals of dinosaurs.

Cryo-electron tomography (cryo-ET) is a powerful technique that can provide unprecedented insight into protein-protein interactions and molecular machinery in a near-native state. The adoption of cryo-ET by life science research groups is hampered by the challenges associated with cryo-ET sample preparation. The current sample preparation process has many steps at which ice contamination may occur to negatively affect the final sample and data quality. A survey was conducted to better understand the effects and impact of ice contamination to the cryo-ET outcome. Over 80 cryo-electron microscopy users worldwide participated in our survey. The results are presented in this article. We furthermore discussed the currently available solutions that can alleviate the ice contamination problems to increase the sample yield and cryo-ET data output.