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Synchronicity is observed in many biological systems, including development, as seen in vertebrate body axis formation, fly eye development, and development of the social amoeba D. discoideum. Despite its prevalence, quantitative analyses of synchronicity at the single-cell level remain rare. Here we show that synchronicity in D. discoideum is mediated by early cAMP signaling. Using single-cell RNA sequencing (scRNA-seq), we quantify transcriptome similarities between individual cells during development. We show that synchronicity first declines upon starvation but then increases with the onset of cAMP-pulse signaling. Synchronicity remains stable throughout development and differs between prespore and prestalk cells. Genetic perturbations of cAMP production and response reveal that cAMP signaling is essential for establishing and maintaining synchronicity, as its absence leads to highly asynchronous development. These findings highlight the role of cAMP signaling in coordinating transcriptomic and morphological synchronicity, and establish scRNA-seq as a tool for quantitative analysis of developmental synchronicity. 

Low-salt-rejection reverse osmosis (LSRRO) is a promising approach for concentrating hypersaline brines using moderate hydraulic pressures, but predictive modeling of LSRRO membranes remains limited by empirical frameworks that require salinity-dependent fitting parameters. Here, we adapt and validate the solution-friction analytical approximation (SF-AA) as a simple, closed-form, and physically grounded model for low-salt-rejection membranes across a wide salinity range. Using three low-salt-rejection membranes, including a highly “leaky” membrane prepared by controlled chlorination, we conducted experiments with NaCl solutions of up to 3.64 M to measure water flux, salt rejection, and salinity-dependent salt permeability. With only three intrinsic membrane parameters, the SF-AA accurately captures the dependence of salt transport on both feed concentration and permeate flux, substantially outperforming the conventional model. These results establish the SF-AA as a robust and generalizable model for LSRRO and other membrane processes with leaky membranes and high salinity. 

Reconfigurable photonic devices capable of dynamically tuning their optical characteristics to adapt to different application demands on-the-fly have become a focus of intensive research and development efforts in recent years. Compared to classical tuning mechanisms relying on thermo-optic or electro-optic effects, the giant nonvolatile refractive index contrast provided by phase change materials (PCMs) upon solid-state structural transitions enables reconfigurable devices with an unprecedented compact footprint, zero static power consumption, and superior optical performance. These unique features have catalyzed phase change photonics, an emerging field characterized by a rapidly evolving research landscape. This review presents a deep dive into this dynamic field, spanning fundamental material design principles and processing techniques to PCM integration into various state-of-the-art device platforms and industry-standard foundry manufacturing processes. We also identify challenges that PCM photonics need to address and point out directions where exciting innovations will likely come to fruition in the near future. 

Semiconductor innovation is increasingly constrained by the complexity, cost, and time involved in developing and optimizing advanced manufacturing processes. Traditional R&D approaches anchored in sequential experimentation and tool-specific workflows create critical bottlenecks that impede progress across the full spectrum of semiconductor technologies, including deposition, patterning, etching, doping, and integration. In this perspective, we present a new paradigm: leveraging semiconductor platforms themselves as engines for accelerating their own advancement. We introduce theEMPOWErframework—ExpeditedManufacturingProcessOptimization throughWafer-scaleExperimentation—which reimagines semiconductor wafers not as passive substrates, but as programmable experimental platforms enabling massively parallel process exploration. By embedding controlled process variability and integrated characterization directly into wafer-scale infrastructure, EMPOWEr addresses long-standing bottlenecks in process optimization, expands the materials and methods accessible to backend integration, and opens new pathways toward agile, scalable, and sustainable semiconductor innovation. This perspective outlines how EMPOWEr can transform semiconductor R&D into a self-reinforcing, high-throughput ecosystem, accelerating both the pace and scope of next-generation microfabrication. 

Abstract Energetic particle deep penetration into low L‐shells (L < 4) impacts the dynamics of the radiation belts and ring current. Previous studies reported that electrons penetrate more frequently, deeply, and faster than protons of similar energies, but underlying mechanisms are unclear. In this study, we compare heavy‐ion behavior with electrons and protons to further identify the underlying mechanisms. Using Van Allen Probes data, we show that electron deep penetration occurs most frequently and deeply, followed by O⁺ions, then He⁺ions, and finally protons. Most particle deep penetrations occur within several hours. Superposed epoch analysis shows that prior to deep penetration, electrons have the steepest phase space density radial gradients, followed by heavy ions and then protons for the sameμandK. Our study suggests that a combination of two or more mechanisms, such as convection electric field and plasma wave‐induced scattering, may be needed to fully explain particle deep penetration.