The article discusses the development of a pH-universal oxygen reduction reaction (ORR) catalyst featuring single-atom iron sites derived from a double-layer metal-organic framework (MOF). This catalyst is designed to enhance the performance of flexible quasi-solid-state rechargeable zinc-air batteries, offering superior energy storage capabilities.

The study investigates the impact of regional carbon efficiency on corporate cash holdings in China. It finds that higher regional carbon efficiency reduces corporate cash holdings by improving debt financing capabilities and encouraging long-term investments. The research highlights the economic consequences of climate change and regional carbon efficiency, contributing to the literature on corporate finance and environmental policy. The study uses a two-way fixed effects model and robustness tests to validate its findings, emphasizing the importance of regional carbon efficiency in balancing economic development and carbon emissions reduction.

Technological advances in optical fields such as imaging, sensing, and devices are highlighted, with a focus on laser technologies and image sensors. The Special Issue compiles contributions from international leaders, covering recent developments in imaging and sensing systems and emerging applications. Key studies include frequency stabilization of diode lasers, surface-enhanced Raman spectra, beam homogenization systems, polarization phasor imaging, dual-wavelength achromatic metalens, 3D reconstruction methods, and multi-image encryption. Optical sensors are noted for their high sensitivity and low cost, with research on precision measurement methods, temperature-compensated strain sensing, and few-mode fiber characterization.

The globalization of trade has significantly impacted global water resources, with virtual water trade offering a new perspective on freshwater sharing and sustainability. This study examines the structural characteristics and drivers of global virtual water trade networks from 2000 to 2015, using multi-regional input-output data and stochastic actor-oriented models. Findings indicate that virtual water flows predominantly from less developed to developed countries, supporting the theory of ecologically unequal exchange. The study also reveals that trade networks are expanding to larger and more distant markets, and that endogenous network structures such as reciprocity and transitive links play a crucial role in the evolution of virtual water trade networks. The research highlights the need for a multidisciplinary approach to water resource management, integrating trade and long-term economic development to promote global water conservation.

A field experiment conducted in the South China Sea in October 2021 studied the impact of a mesoscale warm eddy on acoustic propagation. The experiment involved 105 CTD profiles and an acoustic survey line of about 210 km. The hydrological survey revealed that the warm eddy exhibited surface-intensified, ellipse-like structures with significant temperature and salinity anomalies. Acoustic observations showed that the warm eddy and topography jointly influenced the sound fields, with the warm eddy lengthening the horizontal span of convergence zones by 1.7 km and decreasing their depth by 32 m. The study utilized the Bellhop and Bellhop3D models to simulate the sound fields, revealing anisotropy in the 3D sound fields due to the combined effects of the eddy and topography.

Wong Kueng Hui, a stateless individual in Malaysia, has faced significant challenges due to his status. Despite his aspirations to tour overseas with a punk band, his statelessness confines him to Malaysia. Wong's life in Keningau, Sabah, has been marked by exploitative work, including a grueling job as a bus conductor where he worked excessive hours for less than the minimum wage. His employer paid him only RM 500 instead of the promised RM 800, citing meal allowance deductions. This personal story highlights the broader issues of statelessness and labor exploitation in Malaysia.