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Drawings of THINGS: A large-scale drawing dataset of 1854 object concepts
No full textThe development of large datasets of natural images has galvanized progress in psychology, neuroscience, and computer science. Notably, the THINGS database constitutes a collective effort towards understanding of human visual knowledge by accumulating rich data on a shared set of visual object concepts across several studies. In this paper, we introduce Drawing of THINGS ( DoT ), a novel dataset of 28,627 human drawings of 1854 diverse object concepts, sampled systematically from concrete picturable and nameable nouns in the American English language, mirroring the structure of the THINGS image database. In addition to data on drawings' stroke history, we further collected fine-grained recognition data for each drawing, along with metadata on participant demographics, drawing ability, and mental imagery. We characterize people's ability to communicate and recognize semantic information encoded in drawings and compare this ability to their ability to recognize real-world images of the same visual objects. We also explore the relationship between drawing understanding and the memorability and typicality of the objects contained in THINGS. In sum, we envision DoT as a powerful tool that builds on the THINGS database to advance understanding of how humans express knowledge about visual concepts
Comprehensive Analysis of Key Parameters Determining Formation and Structural Properties of Sol–Gel-Derived Nanoporous Polymers
No full textThis study presents a comprehensive investigation on the relationship between structure, synthesis parameters, and porous properties of sol–gel-derived polymer gels. The formation of the porous gels is monitored with in situ small-angle X-ray scattering, in situ nuclear magnetic resonance spectroscopy (NMR), and NMR cryoporometry. The transition of the reaction solution to a solid gel is governed by the consumption of the phenolic monomer. Primary particle growth and nanopore formation proceed during this short time period and are completed when all resorcinol is consumed. The kinetics of these processes are temperature-dependent and they are completed within 12 min at 120 °C and within 60 min at 80 °C. Extending the reaction time further results in enhanced cross-linking of the polymer, as observed by solid-state 13C NMR spectroscopy. Extended reaction time, i.e., higher degree of polymer cross-linking, enhances pore stability and reduces gel shrinkage during drying, resulting in xerogels with larger pore volume, larger external surface area, and larger average pore sizes. This work rationalizes molecular-scale transformation of polymers with macroscopic properties, thus providing a rational tool for tuning aerogel/xerogel performance through synthesis design
Enhanced ELL Phase Separation Is Crucial for Efficient DNA Damage Repair to Restart Transcription and Cell Survival
No full textDuring genotoxic stress, mammalian cells adapt to resume transcription after repair of damaged DNA. However, mechanisms of these adaptations leading to optimal transcriptional restart are poorly known. In this study, we show critical role of EAF1-mediated enhanced phase separation of elongation factor ELL in its interaction with DNA repair factors for efficient repair of damaged DNA and subsequent transcriptional restart. ELL protein has intrinsic ability to phase separate and form liquid condensates both in vitro and in vivo within mammalian cells. Upon association with EAF1, intrinsic phase separation ability of ELL is enhanced resulting in changes in material property of ELL●EAF1 condensates. Physiologically, upon exposure to genotoxic stress, ATM-mediated phosphorylation-dependent increased EAF1 binding leads to enhanced phase separation and changes the material property of ELL. This, in turn, causes its increased interaction with DNA-PKc and associated Ku complex components. This increased interaction is important for their optimal recruitment on chromatin and corresponding repair of damaged DNA and transcriptional restart. An EAF1 knockdown or ELL mutant that fails to show its enhanced interaction with EAF1 during DNA damage, also fails to show efficient DNA damage repair, transcriptional restart and cell survival after exposure to genotoxic stress
Enhanced Proton Spillover at Pt-Cluster/NiO Interface Reduces the Acidic–Alkaline Hydrogen Evolution Activity Gap
No full textThe sluggish hydrogen evolution reaction (HER) kinetics in alkaline media, primarily attributed to the additional water dissociation step, has led to a significant activity gap between acidic and alkaline conditions. Metal-supported electrocatalysts leveraging hydrogen spillover have garnered significant attention due to sufficiently utilized reaction sites; however, designing active catalysts remains a formidable challenge, primarily due to the limited understanding of the specific regulatory mechanisms governing proton spillover. Herein, a facile strategy is reported for the fabrication of Pt nanoclusters (PtNC) on oxygen-defect-rich NiO nanowires (PtNC-D-NiO). The electrocatalyst demonstrates excellent intrinsic and mass-normalized HER activity and remarkable long-term stability, outperforming PtNC on pristine NiO nanowires and commercial Pt/C. Notably, its alkaline HER activity is fairly close to its acidic counterpart, significantly narrowing the activity gap compared to commercial Pt/C. Advanced ex situ/operando physicochemical characterizations, including in situ electrochemical impedance spectroscopy, reveal that oxygen defects substantially lower the water dissociation energy barrier. This facilitates rapid H* spillover and enhances local H* coverage on PtNC, thus accelerating subsequent H* recombination to boost alkaline HER. This work not only offers a cost-effective catalyst design strategy but also provides fundamental insights into the role of hydrogen spillover in optimizing electrocatalytic performance
