Advances in Soft Materials for Sustainable Electronics

In the current shift from conventional fossil-fuel-based materials to renewable energy,ecofriendly materials have attracted extensive research interest due to their sustainability and biodegradable properties.The integration of sustainable materials in electronics provides industrial benefits from wasted bio-origin resources and preserves the environment.This review covers the use of sustainable materials as components in organic electronics,such as substrates,insulators,semiconductors,and conductors.We hope this review will stimulate interest in the potential and practical applications of sustainable materials for green and sustainable industry.

3D cellular visualization of intact mouse tooth using optical clearing without decalcification

Dental pulp is composed of nerves,blood vessels,and various types of cells and surrounded by a thick and hard enamel-dentin matrix.Due to its importance in the maintenance of tooth vitality,there have been intensive efforts to analyze the complex cellularlevel organization of the dental pulp in teeth.Although conventional histologic analysis has provided microscopic images of the dental pulp,3-dimensional (3D) cellular-level visualization of the whole dental pulp in an intact tooth has remained a technically challenging task.This is mainly due to the inevitable disruption and loss of microscopic structural features during the process of mechanical sectioning required for the preparation of the tooth sample for histological observation.To accomplish 3D microscopic observation of thick intact tissue,various optical clearing techniques have been developed mostly for soft tissue,and their application for hard tissues such as bone and teeth has only recently started to be investigated.In this work,we established a simple and rapid optical clearing technique for intact mouse teeth without the time-consuming process of decalcification.We achieved 3D cellular-level visualization of the microvasculature and various immune cell distributions in the whole dental pulp of mouse teeth under normal and pathologic conditions.This technique could be used to enable diverse research methods on tooth development and regeneration by providing 3D visualization of various pulpal cells in intact mouse teeth.

Rapid species identification of pathogenic bacteria from a minute quantity exploiting three-dimensional quantitative phase imaging and artificial neural network

The healthcare industry is in dire need of rapid microbial identification techniques for treating microbial infections.Microbial infections are a major healthcare issue worldwide,as these widespread diseases often develop into deadly symptoms.While studies have shown that an early appropriate antibiotic treatment significantly reduces the mortality of an infection,this effective treatment is difficult to practice.The main obstacle to early appropriate antibiotic treatments is the long turnaround time of the routine microbial identification,which includes time-consuming sample growth.Here,we propose a microscopy-based framework that identifies the pathogen from single to few cells.Our framework obtains and exploits the morphology of the limited sample by incorporating three-dimensional quantitative phase imaging and an artificial neural network.We demonstrate the identification of 19 bacterial species that cause bloodstream infections,achieving an accuracy of 82.5%from an individual bacterial cell or cluster.This performance,comparable to that of the gold standard mass spectroscopy under a sufficient amount of sample,underpins the effectiveness of our framework in clinical applications.Furthermore,our accuracy increases with multiple measurements,reaching 99.9%with seven different measurements of cells or clusters.We believe that our framework can serve as a beneficial advisory tool for clinicians during the initial treatment of infections.

Handheld endomicroscope using a fiber-optic harmonograph enables real-time and in vivo confocal imaging of living cell morphology and capillary perfusion

Confocal laser endomicroscopy provides high potential for noninvasive and in vivo optical biopsy at the cellular level.Here,we report a fully packaged handheld confocal endomicroscopic system for real-time,high-resolution,and in vivo cellular imaging using a Lissajous scanning fiber-optic harmonograph.The endomicroscopic system features an endomicroscopic probe with a fiber-optic harmonograph,a confocal microscope unit,and an image signal processor.The fiber-optic harmonograph contains a single mode fiber coupled with a quadrupole piezoelectric tube,which resonantly scans both axes at~1 kHz to obtain a Lissajous pattern.The fiber-optic harmonograph was fully packaged into an endomicroscopic probe with an objective lens.The endomicroscopic probe was hygienically packaged for waterproofing and disinfection of medical instruments within a 2.6-mm outer diameter stainless tube capable of being inserted through the working channel of a clinical endoscope.The probe was further combined with the confocal microscope unit for indocyanine green imaging and the image signal processor for high frame rate and high density Lissajous scanning.The signal processing unit delivers driving signals for probe actuation and reconstructs confocal images using the auto phase matching process of Lissajous fiber scanners.The confocal endomicroscopic system was used to successfully obtain human in vitro fluorescent images and real-time ex vivo and in vivo fluorescent images of the living cell morphology and capillary perfusion inside a single mouse.

Water-Excluding Underwater Glue Induced by Marangoni Effect

Marangoni effect at the two-phase interface with different surface tension as a unique mass transfer phenomenon has been widely used in daily life and industrialmanufacture.However,their marvelous liquid-driving capability between miscible liquids has long been ignored,especially in water environments.Here,we first reveal a distinct underwater Marangoni effect between the solvent of glues and the water layer on solid surfaces.Driven by the Marangoni effect,organic solvents with water solubility,high dielectric constant,and low diffusivity could effectively exclude the interfacial water layer,enabling direct and effective contact between glues and solid surfaces.Our experimental results and theoretical simulation proved that a relatively large ratio of the Marangoni number in the horizontal direction and to the vertical direction ensured an effective underwater adhesion of the water-excluding glue.This surface engineering approach provides an alternative to the traditional methods of molecular engineering for realizing underwater adhesion.