Accelerating the Pace of Oxygen Evolution Reaction Catalyst Discovery through Megalibraries.

Iridium (Ir) catalysts are essential for the acidic oxygen evolution reaction (OER) in proton-exchange membrane water electrolyzers (PEMWEs), but their high cost, scarcity, and geographical concentration limit large-scale adoption. In addition, the discovery of non-Ir alternatives is slow due to the vast design space possible. Here, a "megalibrary" is used to explore the catalytic activity of ∼156 million distinct nanostructures comprised of Ru, Co, Mn, and Cr to find alternatives to Ir catalysts for OER.

TiO Nanohelices Decorated with Homogeneous Au-Core Pd-Shell Nanocatalysts for Selective Toluene Gas Detection.

The precise decoration of bimetallic nanocrystals (NCs) with uniform size and homogeneous composition on metal oxide (MOX) surfaces is crucial for developing highly sensitive and selective MOX-based gas sensors. In this study, MOX-based gas sensors are present decorated with homogeneous Au-Pd bimetallic (Au@Pd) NCs synthesized via seed-mediated sequential reduction of Au and Pd on an array of TiO nanohelices (NHs) matrix. Due to the uniform composition, size, and dispersion of the bimetallic NCs, the sensor exhibits outstanding toluene (CH) sensing performance.

Stabilized Co Single-Atom Catalyst via Ion Implantation for Efficient Hydrogen Production.

Although single-atom catalysts (SACs) are garnering significant attention due to their exceptional catalytic properties, the synthesis of SACs remains challenging due to their thermodynamic instability. Herein, stabilized Co-based SACs enabled by the ion implantation technique are presented. It is revealed that implantation of Co ions with an accelerating energy of 120 keV and a controlled fluence not only leads to the formation of stabilized Co single atoms without notable aggregation of Co atoms into nanoclusters, but also induces the creation of defects in the NiO support, such as oxygen vacancies.

Enhancing durability of automotive fuel cells via selective electrical conductivity induced by tungsten oxide layer coated directly on membrane electrode assembly.

The poor durability, attributed to catalyst corrosion during start-up/shutdown (SU/SD), is a major obstacle to the commercialization of fuel cell electric vehicles (FCEVs). We recently achieved durability enhancement under SU/SD conditions by implementing a metal-insulator transition (MIT) using proton intercalation/deintercalation in WO. However, such oxide-supported catalysts were unsuitable for direct application to the mass production stage of membrane electrode assembly (MEA) process due to their physical and chemical properties.

Efficient Alkaline Hydrogen Evolution Reaction Using Superaerophobic Ni Nanoarrays with Accelerated H Bubble Release.

Despite the adverse effects of H bubbles adhering to catalyst's surface on the performance of water electrolysis, the mechanisms by which H bubbles are effectively released during the alkaline hydrogen evolution reaction (HER) remain elusive. In this study, a systematic investigation on the effect of nanoscale surface morphologies on H bubble release behaviors and HER performance by employing earth-abundant Ni catalysts consisting of an array of Ni nanorods (NRs) with controlled surface porosities is performed. Both aerophobicity and hydrophilicity of the catalyst's surface vary according to the surface porosity of catalysts.

Exploring Autonomic Alterations during Seizures in Temporal Lobe Epilepsy: Insights from a Heart-Rate Variability Analysis.

Epilepsy's impact on cardiovascular function and autonomic regulation, including heart-rate variability, is complex and may contribute to sudden unexpected death in epilepsy (SUDEP). Lateralization of autonomic control in the brain remains the subject of debate; nevertheless, ultra-short-term heart-rate variability (HRV) analysis is a useful tool for understanding the pathophysiology of autonomic dysfunction in epilepsy patients. A retrospective study reviewed medical records of patients with temporal lobe epilepsy who underwent presurgical evaluations.

Stratum-Confined Solid-State Reaction (SC-SSR) toward Colloidal Silicon-Based Hollow Nanostructures for Bioapplications.

Silicon nanostructures (SiNSs) can provide multifaceted bioapplications; but preserving their subhundred nm size during high-temperature silica-to-silicon conversion is the major bottleneck. The SC-SSR utilizes an interior metal-silicide stratum space at a predetermined radial distance inside silica nanosphere to guide the magnesiothermic reduction reaction (MTR)-mediated synthesis of hollow and porous SiNSs. In depth mechanistic study explores solid-to-hollow transformation encompassing predefined radial boundary through the participation of metal-silicide species directing the in-situ formed Si-phase accumulation within the narrow stratum.

Tailoring Binding Abilities by Incorporating Oxophilic Transition Metals on 3D Nanostructured Ni Arrays for Accelerated Alkaline Hydrogen Evolution Reaction.

Developing efficient and inexpensive electrocatalysts for the hydrogen evolution reaction (HER) in alkaline water electrolysis plays a key role for renewable hydrogen energy technology. The slow reaction kinetics of HER in alkaline solutions, however, has hampered advances in high-performance hydrogen production. Herein, we investigated the trends in HER activity with respect to the binding energies of Ni-based thin film catalysts by incorporating a series of oxophilic transition metal atoms.

A zero-dimensional predictive model for the pressure drop in the stenotic coronary artery based on its geometric characteristics.

The diameter- or area-reduction ratio measured from coronary angiography, commonly used in clinical practice, is not accurate enough to represent the functional significance of the stenosis, i.e., the pressure drop across the stenosis.

Appropriateness of task of public health doctors in South Korea.

Introduction: Public health doctors (PHDs) in South Korea serve the medically underserved region of South Korea as part of national service duty, but their number has declined in recent years (due to changes in the medical education system). Therefore, there is an increasing need to deploy PHDs efficiently. Consisting of 2138 medical doctors of different specialties, they serve as both primary care physicians and public health experts.

Engineering of a Biomimetic Pericyte-Covered 3D Microvascular Network.

Pericytes enveloping the endothelium play an important role in the physiology and pathology of microvessels, especially in vessel maturation and stabilization. However, our understanding of fundamental pericyte biology is limited by the lack of a robust in vitro model system that allows researchers to evaluate the interactions among multiple cell types in perfusable blood vessels. The present work describes a microfluidic platform that can be used to investigate interactions between pericytes and endothelial cells (ECs) during the sprouting, growth, and maturation steps of neovessel formation.