Fatigue Assessment by Blink Detected with Attachable Optical Sensors of Dye-Sensitized Photovoltaic Cells

This paper demonstrates fatigue assessment based on eye blinks that are detected by dye-sensitized photovoltaic cells. In particular, the sensors were attached to the temple of eyeglasses and positioned at the lateral side of the eye. They are wearable, did not majorly disturb the user's eyesight, and detected the position of the eyelid or the eye state. The optimal location of the sensor was experimentally investigated by evaluating the detection accuracy of blinks. We conducted fatigue assessment experiments using the developed wearable system, or smart glasses. Several parameters, including the frequency, duration, and velocity of eye blinks, were extracted as fatigue indices. Successful fatigue assessment by the proposed system will be of great benefit for maximizing performance and maintenance of physical/mental health.

Liquid Metal Combinatorics toward Materials Discovery

Liquid metals and their derivatives provide several opportunities for fundamental and practical exploration worldwide. However, the increasing number of studies and shortage of desirable materials to fulfill different needs also pose serious challenges. Herein, to address this issue, a generalized theoretical frame that is termed as "Liquid Metal Combinatorics" (LMC) is systematically presented, and summarizes promising candidate technical routes toward new generation material discovery. The major categories of LMC are defined, and eight representative methods for manufacturing advanced materials are outlined. It is illustrated that abundant targeted materials can be efficiently designed and fabricated via LMC through deep physical combinations, chemical reactions, or both among the main bodies of liquid metals, surface chemicals, precipitated ions, and other materials. This represents a large class of powerful, reliable, and modular methods for innovating general materials. The achieved combinatorial materials not only maintained the typical characteristics of liquid metals but also displayed distinct tenability. Furthermore, the fabrication strategies, wide extensibility, and pivotal applications of LMC are classified. Finally, by interpreting the developmental trends in the area, a perspective on the LMC is provided, which warrants its promising future for society.

Fabrication and Evaluation of Dissolving Hyaluronic Acid Microneedle Patches for Minimally Invasive Transdermal Drug Delivery by Nanoimprinting

Transdermal drug delivery minimizes pain and provides a controlled, stable release of drugs, but its effectiveness is limited by the skin's natural barriers. Microneedles overcome this problem, enabling minimally invasive drug delivery. Microneedle patches (MNPs) with 80 µm-tall needles composed of hyaluronic acid (HA) were developed and evaluated for their formability, structural integrity, dissolution rate, skin penetration ability, and drug transmission capacity. The influence of the molecular weight of HA on these properties was also investigated. MNPs made from low-molecular-weight HA (30 kDa-50 kDa) demonstrated 12.5 times superior drug permeability in ex vivo human skin compared to needleless patches (NLPs). Furthermore, in the same test, low-molecular-weight HA MNPs had 1.7 times higher drug permeability than high-molecular-weight HA MNPs, suggesting superior transdermal administration. The molecular weight of HA significantly influenced its solubility and permeability, highlighting the potential effectiveness of MNPs as drug delivery systems. Puncture tests demonstrated a penetration depth of 50-60 µm, indicating minimal nerve irritation in the dermis and effective drug delivery to the superficial dermal layer. These results present a manufacturing technique for MNPs incorporating model drug compounds and highlight their potential as a novel and minimally invasive drug delivery method for the biomedical applications of soft gels.

Advanced Fog Harvesting Method by Coupling Plasma and Micro/Nano Materials

Harvesting fog is a potential and effective way to alleviate the crisis of water resource shortage. A highly efficient and economical fog harvesting method has always been a global and common goal. Here, a promising fog harvesting method by coupling plasma and micro/nano materials is proposed, which can achieve 93% fog collection efficiency with consuming power of only 0.76 W/0.04 m2. The basic method is to utilize nanoparticles to decorate both the discharge electrode and the collecting electrode of the micro/nano electrostatic fog collector. For the discharge electrode, the nanoparticles can achieve an order of magnitude higher electric field strength and a 28.6% decrease in the operating voltage (14 kV decreases to 10 kV). For the collecting electrode, a novel composite structure of hydrophobic/hydrophilic (HB/HL) is proposed. The core advantage is the directional droplet transport at the junction of HB and HL caused by surface tension can adjust the accumulated droplets on the two sides, which avoids the droplet residue and mesh blockage in the general structure. This technology provides an innovative approach for the collection of microdroplets and a new design idea for the fog collector to deal with the water crisis.