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Creators/Authors contains: "Park, Sehyun"

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  1. Abstract Microfluidic‐based wearable electrochemical sensors represent a transformative approach to non‐invasive, real‐time health monitoring through continuous biochemical analysis of body fluids such as sweat, saliva, and interstitial fluid. These systems offer significant potential for personalized healthcare and disease management by enabling real‐time detection of key biomarkers. However, challenges remain in optimizing microfluidic channel design, ensuring consistent biofluid collection, balancing high‐resolution fabrication with scalability, integrating flexible biocompatible materials, and establishing standardized validation protocols. This review explores advancements in microfluidic design, fabrication techniques, and integrated electrochemical sensors that have improved sensitivity, selectivity, and durability. Conventional photolithography, 3D printing, and laser‐based fabrication methods are compared, highlighting their mechanisms, advantages, and trade‐offs in microfluidic channel production. The application section summarizes strategies to overcome variability in biofluid composition, sensor drift, and user adaptability through innovative solutions such as hybrid material integration, self‐powered systems, and AI‐assisted data analysis. By analyzing recent breakthroughs, this paper outlines critical pathways for expanding wearable sensor technologies and achieving seamless operation in diverse real‐world settings, paving the way for a new era of digital health. 
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    Free, publicly-accessible full text available March 18, 2026
  2. Abstract As known, n‐type inorganic semiconductor nanoparticles such as zinc oxide nanoparticles have been explored in various sensing applications, which demand high‐density electronic elements placement for rapid operation. Herein, high‐resolution designs of conductive channels of noble metal‐doped zinc oxide nanoparticles is demonstrated using an engraving transfer printing process and silver metal doping approach. Such thin‐film transistors with reduced feature size to 2 µm fabricated exhibited significantly enhanced electron mobility up 3.46 × 10−2cm2V−1s−1and light sensitivity. Furthermore, the integration of this micropatterning technology and metal doping in thin‐film transistors is utilized for control of current–voltage characteristics under the ultraviolet radiation with high sensitivity. It is suggested that this approach to design of doped inorganic nanoparticle channels paves the way for high‐density thin‐film transistors suitable for optoelectronic circuit, UV photodetectors and neuromorphic computing systems. 
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    Free, publicly-accessible full text available February 2, 2026
  3. We measure 95.6±0.3% storage efficiency of ultrafast photons in a collisionally broadened barium vapor quantum memory. We measure 31±1% total efficiency, limited by control field power, and a 0.515(6) ns lifetime, limited by motional dephasing. 
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  4. We report record storage efficiencies in the first atomic THz-bandwidth quantum memory. Near-off-resonant orbital transitions in collisionally broadened hot atomic barium vapor allow for 83% storage efficiency, 25% total efficiency, and a time-bandwidth-product of 800. 
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  5. null (Ed.)
    Recent advances in nanomaterial preparation and printing technologies provide unique opportunities to develop flexible hybrid electronics (FHE) for various healthcare applications. Unlike the costly, multi-step, and error-prone cleanroom-based nano-microfabrication, the printing of nanomaterials offers advantages, including cost-effectiveness, high-throughput, reliability, and scalability. Here, this review summarizes the most up-to-date nanomaterials, methods of nanomaterial printing, and system integrations to fabricate advanced FHE in wearable and implantable applications. Detailed strategies to enhance the resolution, uniformity, flexibility, and durability of nanomaterial printing are summarized. We discuss the sensitivity, functionality, and performance of recently reported printed electronics with application areas in wearable sensors, prosthetics, and health monitoring implantable systems. Collectively, the main contribution of this paper is in the summary of the essential requirements of material properties, mechanisms for printed sensors, and electronics. 
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  6. Abstract The development of wireless implantable sensors and integrated systems, enabled by advances in flexible and stretchable electronics technologies, is emerging to advance human health monitoring, diagnosis, and treatment. Progress in material and fabrication strategies allows for implantable electronics for unobtrusive monitoring via seamlessly interfacing with tissues and wirelessly communicating. Combining new nanomaterials and customizable printing processes offers unique possibilities for high‐performance implantable electronics. Here, this report summarizes the recent progress and advances in nanomaterials and printing technologies to develop wireless implantable sensors and electronics. Advances in materials and printing processes are reviewed with a focus on challenges in implantable applications. Demonstrations of wireless implantable electronics and advantages based on these technologies are discussed. Lastly, existing challenges and future directions of nanomaterials and printing are described. 
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