News from Science China Press

Recently, a research team led by Tianjin University, in collaboration with the Aerospace Information Research Institute of the Chinese Academy of Sciences and Southern University of Science and Technology, published a paper in National Science Review. They proposed a novel bilayer terahertz metasurface architecture based on S₄ point-group symmetry, achieving symmetry-protected quasi-bound states in the continuum (QBICs) with exceptional robustness against structural defects and fabrication imperfections. This breakthrough overcomes the longstanding bottleneck of conventional QBICs being highly sensitive to structural perturbations, providing a practical paradigm for the scalable manufacturing of high-performance terahertz photonic devices.

Recognizing ecosystems as legitimate water users alongside humans, researchers conducted the first global assessment of ecological water scarcity across 1,182 river basins. In the 2000s, 412 basins (35%) experienced ecological water scarcity. Human interventions contributed to 53% of seasonal and 60% of annual ecological water scarcity cases. Future risks are expected to persist, highlighting the importance of climate change mitigation and environmental flow protection.

Using 448.1 million ψ(3686) events collected with the BESIII detector, researchers have determined the complete spin density matrix of a Λ-Λ̄   pair for the first time in this decay. The measurement reveals significant transverse Λ polarization and provides evidence of quantum nonlocality through a 3.7 sigma violation of the CHSH inequality.

Rocks from a South China section record an extreme burst of geomagnetic polarity reversals−about 11 per million years−across the end-Guadalupian mass extinction roughly 261 million years ago. The rate is among the highest known in Earth’s history. Researchers speculate the instability may reflect deep-mantle changes that briefly weakened magnetic shielding, adding stress to an already troubled biosphere, though a direct causal role remains unproven.

A review in Science China Chemistry, jointly written by 15 research groups in China, summarizes key advances in CO₂ capture and utilization. It covers capture methods and electrocatalytic, photocatalytic and thermocatalytic conversion, discusses current challenges and future directions, and provides a reference for researchers and industry.

A Zhejiang University-led team used ribosome profiling, RNA sequencing, and 16S rRNA sequencing to study immune translation in healthy and weaning piglets. Weaning triggered widespread translational reprogramming of immune genes and a shift toward GC-ending codons. Gut microbiota from weaned piglets also showed GC-enriched codon profiles and was linked to host immune gene translation. The findings suggest a previously unrecognized association between microbiota composition and codon-usage-linked translational control during early-life stress.

Researchers have developed a groundbreaking electrocatalytic system that purifies contaminated water by generating its own oxygen supply internally. By spatially decoupling oxygen capture and electron donation sites on the catalyst, the design overcomes critical bottlenecks in conventional water treatment. This "self-aeration" system achieves near-100% selectivity in producing highly reactive singlet oxygen to destroy pollutants. The innovation eliminates the need for energy-intensive external aeration, cutting electricity costs by 95% and offering a robust, eco-friendly solution for tackling global water pollution.