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We tested the impact of a 15-minute VR training on spatial skills and performance on a geoscience task with a control group. The VR group improved more on the Water Level Task-a measure of understanding of horizontal (B = 0.68, p=0.008). Both groups performed equally on the geology task, except for an orientation rule not well instructed in the VR module (B = -1.33, p=0.0057). In the post-survey, the VR group reported higher ability to link knowledge (X2=4.45, p=0.035) and more interest than in past activities (X2=8.47, p=0.004). This is encouraging, given the brevity of the VR lesson. 

To bring real-world applications of DNA nanostructures to fruition, advanced microscopy techniques are needed to shed light on factors limiting the availability of addressable sites. Correlative microscopy, where two or more microscopies are combined to characterize the same sample, is an approach to overcome the limitations of individual techniques, yet it has seen limited use for DNA nanotechnology. We have developed an accessible strategy for high resolution, correlative DNA-based points accumulation for imaging in nanoscale topography (DNA-PAINT) super-resolution and atomic force microscopy (AFM) of DNA nanostructures, enabled by a simple and robust method to selectively bind DNA origami to cover glass. Using this technique, we examined addressable “docking” sites on DNA origami to distinguish between two defect scenarios–structurally incorporated but inactive docking sites, and unincorporated docking sites. We found that over 75% of defective docking sites were incorporated but inactive, suggesting unincorporated strands played a minor role in limiting the availability of addressable sites. We further explored the effects of strand purification, UV irradiation, and photooxidation on availability, providing insight on potential sources of defects and pathways toward improving the fidelity of DNA nanostructures. 

Abstract DNA is a compelling alternative to non-volatile information storage technologies due to its information density, stability, and energy efficiency. Previous studies have used artificially synthesized DNA to store data and automated next-generation sequencing to read it back. Here, we report digital Nucleic Acid Memory (dNAM) for applications that require a limited amount of data to have high information density, redundancy, and copy number. In dNAM, data is encoded by selecting combinations of single-stranded DNA with (1) or without (0) docking-site domains. When self-assembled with scaffold DNA, staple strands form DNA origami breadboards. Information encoded into the breadboards is read by monitoring the binding of fluorescent imager probes using DNA-PAINT super-resolution microscopy. To enhance data retention, a multi-layer error correction scheme that combines fountain and bi-level parity codes is used. As a prototype, fifteen origami encoded with ‘Data is in our DNA!\n’ are analyzed. Each origami encodes unique data-droplet, index, orientation, and error-correction information. The error-correction algorithms fully recover the message when individual docking sites, or entire origami, are missing. Unlike other approaches to DNA-based data storage, reading dNAM does not require sequencing. As such, it offers an additional path to explore the advantages and disadvantages of DNA as an emerging memory material. 

This paper offers an overview of verbal tone melodies within Luyia, a cluster of Bantu languages spoken in Kenya and Uganda. Luyia tone is diverse, possessing three types of verbal tonal systems: 'conservative', 'predictable', and 'reversive'. We illustrate the general tonal characteristics of each type of system with an exemplar language variety, describing the complex interactions of lexical and melodic tones.