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Abstract Jakobshavn Isbræ, a major outlet glacier in Greenland, lost its protective ice shelf in 2002 and has been speeding up and retreating since. We image its grounding line for the first time with a terrestrial radar interferometer deployed in 2016 and detect its migration at tidal frequencies. The southern half of the glacier develops a floating section (3 km × 3 km) that migrates in phase with the tidal difference, up to a distance of 2.8 km, far more than previously expected. We attribute the migration to kilometer‐scale seawater intrusions, 10–20 cm in height, with the tide. The intrusions reveal that the glacier bed may be up to 800 m deeper than expected on the south side, which illustrates that our knowledge of bed topography remains limited for this glacier. We expect seawater intrusions to cause rapid melt of basal ice and play a major role in the glacier evolution. 

All proteins are translated in the cytoplasm, yet many, including transcription factors, play vital roles in the nucleus. While previous research has concentrated on molecular motors for the transport of these proteins to the nucleus, recent observations reveal perinuclear accumulation even in the absence of an energy source, hinting at alternative mechanisms. Here, we propose that structural properties of the cellular environment, specifically the endoplasmic reticulum (ER), can promote molecular transport to the perinucleus without requiring additional energy expenditure. Specifically, physical interaction between proteins and the ER impedes their diffusion and leads to their accumulation near the nucleus. This result explains why larger proteins, more frequently interacting with the ER membrane, tend to accumulate at the perinucleus. Interestingly, such diffusion in a heterogeneous environment follows Chapman’s law rather than the popular Fick’s law. Our findings suggest a novel protein transport mechanism arising solely from characteristics of the intracellular environment. 

Abstract Use of single‐atom catalysts (SACs) has become a popular strategy for tuning activity and selectivity toward specific pathways. However, conventional SAC synthesis methods require high temperatures and pressures, complicated procedures, and expensive equipment. Recently, underpotential deposition (UPD) has been investigated as a promising alternative, yielding high‐loading SAC electrodes under ambient conditions and within minutes. Yet only few studies have employed UPD to synthesize SACs, and all have been limited to UPD of Cu. In this work, a flexible UPD approach for synthesis of mono‐ and bi‐metallic Cu, Fe, Co, and Ni SACs directly on oxidized, commercially available carbon electrodes is reported. The UPD mechanism is investigated using in situ X‐ray absorption spectroscopy and, finally, the catalytic performance of a UPD‐synthesized Co SAC is assessed for electrochemical nitrate reduction to ammonia. The findings expand upon the usefulness and versatility of UPD for SAC synthesis, with hopes of enabling future research toward realization of fast, reliable, and fully electrified SAC synthesis processes.