A 3D-printed phantom for quality-controlled reproducibility measurements of arterial spin labeled perfusion.

Purpose: To develop a portable MR perfusion phantom for quality-controlled assessment and reproducibility of arterial spin labeled (ASL) perfusion measurement.

Methods: A 3D-printed perfusion phantom was developed that mimics the branching of arterial vessels, capillaries, and a chamber containing cellulose sponge representing tissue characteristics. A peristaltic pump circulated distilled water through the phantom, and was first evaluated at 300, 400, and 500 mL/min.

Reversible switches of DNA nanostructures between "Closed" and "Open" states and their biosensing applications.

A novel and versatile biosensing platform based on the structural conversion of 3D DNA nanostructures from ETDNA (Equilateral Triangle) to TPFDNA (Triangular Pyramid Frustum) was proposed for the first time. The inputs of aptamers and their relative targets made the DNA structure change from the "Open" to the "Closed" state, leading to the faradaic impedance changes as the output signals. The specific properties of excellent stability and specific rigid structure of 3D DNA nanostructures made the biosensor function as a regenerable, reusable and intelligent platform.