Korea University of Technology and Education

This article proposes a novel resonator structure for wireless power transfer (WPT) in autonomous vehicle seat applications. The proposed WPT system employs helical coils for both the transmitter and receiver (RX), achieving a high coupling coefficient exceeding 0.5 across a substantial RX movement range. To mitigate the complexity of the system due to RX movement, an <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$M$</tex-math> </inline-formula>-uniform resonator with unequal turn spacing was developed using a genetic algorithm based on theoretical analysis. While the RX was moving, the proposed <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$M$</tex-math> </inline-formula>-uniform resonator reduced the receiving-side voltage and current variations to 5.8% and 4.4%, respectively. This represents a significant improvement over the 34.1% and 37.0% observed in conventional coil designs with equal turn spacing. Additionally, the proposed system maintained a total system efficiency above 85% over the entire RX movement range, demonstrating its suitability for dynamic WPT applications without the need for RX position detection systems. In conclusion, the proposed resonator overcomes the tangling and reliability issues of traditional power cables, enabling flexible seat movement in future autonomous vehicles to optimize their interior space.

Liquid-solid triboelectric nanogenerators (L-S TENGs) enable the harvesting of electrical energy through interactions between water droplets and solid surfaces. In particular, droplet-based electricity generators (DEGs) utilize the impact and spreading behavior of water droplets on dielectric materials to convert mechanical energy into electricity. Most existing DEG systems rely on synthetic polymers because of their excellent triboelectric characteristics. In this study, a Nafion-functionalized cellulose nanocrystal (Nf-CNCs) film is introduced to enhance the triboelectric performance in a DEG configuration. Cellulose nanocrystals, owing to their high dielectric constant, pronounced crystallinity, and ordered molecular structure, represent an ideal sustainable material for triboelectric energy conversion. The fabricated DEG device demonstrated stable electrical performance over a broad range of droplet kinetic conditions. It achieves a peak power density of approximately 310 mW/m2. Parametric investigations reveal the effects of droplet diameter, impact velocity, and impingement position on device performance. Furthermore, long-term durability tests demonstrate stable open-circuit voltage and current, confirming the device's robustness. The DEG device delivers sufficient power to directly activate low-power electronics such as LEDs, underscoring its potential as an eco-friendly and scalable platform for ambient mechanical energy harvesting from water droplets.

Background/Objectives: Osteoarthritis (OA) is a pervasive chronic joint disease characterized by the triad of persistent articular cartilage degeneration, debilitating synovial inflammation, and sustained chronic pain. Although salmon nasal cartilage proteoglycan (SPG) is recognized for supporting joint health, the precise molecular mechanism underlying its effects during OA progression remains to be fully elucidated. This study evaluated the therapeutic efficacy of SPG using a monosodium iodoacetate (MIA)-induced mouse model. Methods: A total of 180 male C57BL/6J mice (six-week-old) were utilized, organized into three independent cohorts to analyze distinct analytical endpoints: (1) pain assessment, histology, and immunohistochemistry; (2) mRNA expression analysis for early-stage OA (Day 3); and (3) mRNA expression analysis for the late-stage OA (Day 28). All subjects received daily oral treatment via gavage, commencing 5 days prior to OA induction and continuing until the designated experimental termination points (either Day 3 or Day 28). Each cohort comprised five experimental groups (n = 10–12 per group): a saline-injected Sham group, an MIA-induced Control group, a positive comparator receiving celecoxib (CLX, 20 mg/kg/day), and two groups administered SPG at a dose of 50 or 100 mg/kg/day. Results: Our findings demonstrated that SPG, particularly at the 100 mg/kg dose, significantly mitigated joint pain symptoms, performing comparably to CLX. Histopathological assessments confirmed that SPG effectively preserved the structural integrity of the cartilage matrix and substantially reduced pathological damage, as evidenced by lower Mankin scores. Mechanistically, SPG treatment led to a marked downregulation of degradative enzymes, including matrix metalloproteinase-3 (MMP-3) and a disintegrin and metalloproteinase with thrombospondin motifs 4 (ADAMTS-4), while concurrently normalizing the levels of tissue inhibitors of metalloproteinases (TIMPs). Furthermore, SPG prevented the aberrant, over-compensatory expression of anabolic markers such as SRY-box transcription factor 9 (SOX-9), type II collagen alpha 1 chain (COL2A1), and aggrecan (ACAN) typically observed in the disease’s later stages. While SPG demonstrated a limited impact on broadly pro-inflammatory cytokine profiles, it specifically and significantly reduced interleukin-6 (IL-6) gene expression during the chronic phase. Conclusions: These results suggest that SPG serves as a promising natural agent that maintains articular homeostasis by balancing matrix metabolic pathways, positioning it as a scientifically validated functional food candidate for the management of joint health.

Seawater Electrolysis Seawater electrolysis can be advanced through screening of cathode materials. Oxophilic vanadium dopants embedded in a nickel host act as anchors that facilitate the water dissociation step in the alkaline hydrogen evolution reaction. In their Research Article (10.1002/adfm.202516387) Jeong Woo Han and co-workers also explore how oxophilic dopants influence competitive chloride adsorption and metal hydroxide precipitation, offering insights into catalyst durability and performance under seawater conditions.