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Debugging process plays a crucial role in helping students pinpoint their specific learning weaknesses, allowing them to modify their strategies for enhanced academic performance. Notably, changes in pupil dilation serve as an indicator of arousal associated with confronting learning challenges. This physiological response acts as a “physiological footprint” that reflects cognitive engagement, facilitating internally focused cognitive processes such as insight generation and mind-wandering. In this study, we proposed that pupil dilation could be a valuable predictor of students’ metacognitive awareness throughout the debugging process, specifically within an augmented reality (AR) learning environment. The findings revealed significant differences in pupil dilation among students categorized by their varying levels of debugging, which represents a specific dimension of the Metacognitive Awareness Inventory. 

Abstract Reconstructing past oxygen fluctuations in oxygen minimum zones (OMZs) is crucial for understanding their response to climate change. Numerous studies suggest better oxygenation in the Arabian Sea OMZ during the Last Glacial Maximum (LGM) compared to the Holocene. However, bottom water oxygen (BWO) variability during the Penultimate Glacial Cycle (Marine Isotope Stage [MIS] 6 to MIS 5e, ∼140–115 ka B.P.) remains poorly constrained. This study reconstructs BWO variations during this period from sediment core TN041‐8JPC in the western Arabian Sea OMZ, utilizing proxies including benthic foraminiferal surface porosity, redox‐sensitive trace metal enrichment factors (e.g., U_EF), and U/Ba ratios. Bottom water oxygen concentrations were 24.4 ± 5.9 μmol/kg during MIS 6 and 16.8 ± 6.5 μmol/kg during MIS 5e, with all proxies indicating higher BWO in MIS 6 than in MIS 5e. However, these proxies show different patterns within MIS 5e, indicating that U_EFand U/Ba ratios may be limited to recording average BWO in glacial and interglacial (quasi)steady states. We propose that the intensified OMZ during MIS 5e, relative to MIS 6, was driven by higher productivity, temperature‐induced reductions in oxygen solubility, and reduced delivery of Southern‐sourced intermediate waters. In contrast, the intensified OMZ during the Holocene, compared to the LGM, was likely influenced by lower oxygen solubility, reduced Southern water delivery, and winter convective mixing rather than productivity. This study highlights a general trend of weaker OMZs in glacial than interglacial periods, though the mechanisms may not be identical, offering insights into OMZ dynamics under climate change in the past. 

Superlattices of polyhedral nanocrystals exhibit emergent properties defined by their structural arrangements, but native nanocrystal ligands often limit their programmability. Polymeric ligands address this limitation by enabling tunable nanocrystal softness through modifications of polymer molecular weight and grafting density. Here, we investigate phase transitions in polymer-grafted nanooctahedra by varying polymer length, nanocrystal size, truncation, and ligand density. In two-dimensional superlattices, longer polymers or smaller nanooctahedra induce a transition from orientationally ordered to hexagonal rotator lattices. In three-dimensional superlattices, increasing polymer length drives transitions from Minkowski to body-centered cubic and plastic hexagonal close-packed phases, while higher grafting densities further enable transitions to simple hexagonal phases. Polymer brush and thermodynamic perturbation theories, supported by Monte Carlo simulations, uncover the entropic and enthalpic forces that govern these transitions. This work highlights the versatility of polymer-grafted anisotropic nanocrystals as building blocks for designing hierarchical superstructures and metamaterials with customizable properties. 

Abstract In all three domains of life, genes with related functions can be organized into specific genomic regions known as gene clusters. In eukaryotes, histone, piRNA (Piwi-interacting RNA), and rDNA (ribosomal DNA) clusters are among the most notable clusters which play fundamental roles in chromatin formation, genome integrity, and translation, respectively. These clusters have long been thought to be regulated by distinct transcriptional mechanisms. In this study, using Caenorhabditis elegans as a model system we identify ATTF-6, a member of the AT-hook family, as a key factor for the expression of histone, piRNA, and 5S rDNA-SL1 (spliced leader 1) clusters. ATTF-6 is essential for C. elegans viability. It forms distinct nuclear foci at both piRNA and 5S rDNA-SL1 clusters. Loss of ATTF-6 leads to a depletion of histone mRNAs, SL1 transcripts, and piRNAs. Additionally, we demonstrate that ATTF-6 is required for the recruitment of USTC (Upstream Sequence Transcription Complex) to piRNA clusters, which is necessary for piRNA production. Collectively, our findings reveal a unifying role for an AT-hook transcription factor in promoting the expression of fundamental gene clusters. 

With the discovery of gravitational waves (GWs), the disks of Active Galactic Nuclei (AGN) have emerged as an interesting environment for hosting a fraction of their sources. AGN disks are conducive to forming both long and short Gamma-Ray Bursts (GRBs), and their anticipated cosmological occurrence within these disks has potential to serve as an independent tool for probing and calibrating the population of stars and compact objects within them, and their contribution to the GW-detected population. In this study, we employ Monte Carlo methods in conjunction with models for GRB electromagnetic emission in extremely dense media to simulate the cosmological occurrence of both long and short GRBs within AGN disks, while also estimating their detectability across a range of wavelengths, from gamma-rays to radio frequencies. {We investigate two extreme scenarios: “undiffused”, in which the radiation escapes without significant scattering (i.e. if the progenitor has excavated a funnel within the disk), and “diffused”, in which the radiation is propagated through the high-density medium, potentially scattered and absorbed. {In the diffused case,} we find that the majority of detectable GRBs are likely to originate from relatively low redshifts, and from the outermost regions of large supermassive black hole (SMBH) masses, . In the undiffused case, we expect a similar trend, but with a considerable contribution from the intermediate regions of lower SMBH masses. Detectable emission is generally expected to be dominant in prompt $\gamma$-rays if diffusion is not dominant, and X-ray afterglow if diffusion is important; however, the nature of the dominant observable signal highly depends on the specific AGN disk model, hence making GRBs in AGN disks also potential probes of the structure of the disks themselves.