We demonstrate the first reported methodology using nanowires that unveils massive numbers of cancer-related urinary microRNAs.

Rapid development of artificial intelligence techniques ignites the emerging demand on accurate perception and understanding of optical signals from external environments via brain-like visual systems. Here, enabled by quasi–two-dimensional electron gases (quasi-2DEGs) in InGaO₃(ZnO)₃ superlattice nanowires (NWs), an artificial visual system was built to mimic the human ones. This system is based on an unreported device concept combining coexistence of oxygen adsorption-desorption kinetics on NW surface and strong carrier quantum-confinement effects in superlattice core, to resemble the biological Ca²⁺ ion flux and neurotransmitter release dynamics. Given outstanding mobility and sensitivity of superlattice NWs, an ultralow energy consumption down to subfemtojoule per synaptic event is realized in quasi-2DEG synapses, which rivals that of biological synapses and now available synapse-inspired electronics. A flexible quasi-2DEG artificial visual system is demonstrated to simultaneously perform high-performance light detection, brain-like information processing, nonvolatile charge retention, in situ multibit-level memory, orientation selectivity, and image memorizing.

Single-use disposable nonvolatile memory devices hold promise for novel applications in internet of everything (IoE) technology by storing the health status of individual humans in daily life. However, conventional memory devices are not disposable because they are mostly composed of non-renewable, non-biodegradable and sometimes toxic materials, causing serious damage to ecological systems when they are released to the environment. Here, we demonstrate an environment-friendly, disposable nonvolatile memory device composed of 99.3 vol.% nanocellulose. Our memory device consists of a nanocellulose-based resistive-switching layer and a nanopaper substrate. The device exhibited nonvolatile resistive switching with the capability of multilevel storage and potential scalability down to the single nanofiber level (ca. 15 nm). The biodegradability of our memory device was confirmed by burying it in natural soil for 26 days.