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People with blindness have limited access to the high-resolution graphical data and imagery of science. Here, a lithophane codex is reported. Its pages display tactile and optical readouts for universal visualization of data by persons with or without eyesight. Prototype codices illustrated microscopy of butterfly chitin—fromN-acetylglucosamine monomer to fibril, scale, and whole insect—and were given to high schoolers from the Texas School for the Blind and Visually Impaired. Lithophane graphics of Fischer-Spier esterification reactions and electron micrographs of biological cells were also 3D-printed, along with x-ray structures of proteins (as millimeter-scale 3D models). Students with blindness could visualize (describe, recall, distinguish) these systems—for the first time—at the same resolution as sighted peers (average accuracy = 88%). Tactile visualization occurred alongside laboratory training, synthesis, and mentoring by chemists with blindness, resulting in increased student interest and sense of belonging in science. 

Surfactant protein D (SP-D) is an essential component of the human pulmonary surfactant system, which is crucial in the innate immune response against glycan-containing pathogens, including Influenza A viruses (IAV) and SARS-CoV-2. Previous studies have shown that wild-type (WT) SP-D can bind IAV but exhibits poor antiviral activities. However, a double mutant (DM) SP-D consisting of two point mutations (Asp325Ala and Arg343Val) inhibits IAV more potently. Presently, the structural mechanisms behind the point mutations' effects on SP-D's binding affinity with viral surface glycans are not fully understood. Here we use microsecond-scale, full-atomistic molecular dynamics (MD) simulations to understand the molecular mechanism of mutation-induced SP-D's higher antiviral activity. We find that the Asp325Ala mutation promotes a trimannose conformational change to a more stable state. Arg343Val increases the binding with trimannose by increasing the hydrogen bonding interaction with Glu333. Free energy perturbation (FEP) binding free energy calculations indicate that the Arg343Val mutation contributes more to the increase of SP-D's binding affinity with trimannose than Asp325Ala. This study provides a molecular-level exploration of how the two mutations increase SP-D binding affinity with trimannose, which is vital for further developing preventative strategies for related diseases. 

Blind and sighted persons can now share and visualize the same piece of data using tactile graphics that glow in ambient light.