From 2014 to 2020, we compiled radiocarbon ages from the lower 48 states, creating a database of more than 100,000 archaeological, geological, and paleontological ages that will be freely available to researchers through the Canadian Archaeological Radiocarbon Database. Here, we discuss the process used to compile ages, general characteristics of the database, and lessons learned from this exercise in “big data” compilation.

The Murchison Widefield Array (MWA) is an open access telescope dedicated to studying the low-frequency (80–300 MHz) southern sky. Since beginning operations in mid-2013, the MWA has opened a new observational window in the southern hemisphere enabling many science areas. The driving science objectives of the original design were to observe 21 cm radiation from the Epoch of Reionisation (EoR), explore the radio time domain, perform Galactic and extragalactic surveys, and monitor solar, heliospheric, and ionospheric phenomena. All together $60+$ programs recorded 20 000 h producing 146 papers to date. In 2016, the telescope underwent a major upgrade resulting in alternating compact and extended configurations. Other upgrades, including digital back-ends and a rapid-response triggering system, have been developed since the original array was commissioned. In this paper, we review the major results from the prior operation of the MWA and then discuss the new science paths enabled by the improved capabilities. We group these science opportunities by the four original science themes but also include ideas for directions outside these categories.

In this study, we report on the mechanical cleavage of conductive metal-based aluminum diboride (AlB2) flakes. The cleavage resulted in a highly single crystalline 2D material and had an atomically flat and smooth surface as shown by atomic force microscopy (AFM) and secondary ion mass spectrometry. Nanoindentation and AFM imaging of freshly cleaved specimens revealed sub-nm roughness and 30% improvement in the nanomechanical properties as compared to the as-grown AlB2 flakes. Once exposed to ambient air, the cleaved AlB2 flakes formed a superficial oxidation layer of less than 1 nm thickness within 5 min. Owing to the smooth surface, ultra-thin and stable oxide layer, and the excellent mechanical and electrical characteristics of AlB2, the cleaved flakes present an ideal 2D material for emerging applications in microfabrication such as the growth of epitaxial thin films. To prove the sub-nm surface characteristics of cleaved AlB2, a 10-nm thick TiO2 film was deposited on a freshly cleaved AlB2 using atomic layer deposition. Surface roughness and compositional consistency of this film were compared with a control sample deposited on Si. The TiO2 film on AlB2 showed a distinct thin interface layer with fewer defects than TiO2 on Si and superior flatness.