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1. A Rapid Ionization Change in the Nebular-phase Spectra of the Type Ia SN 2011fe

   https://doi.org/10.3847/2041-8213/ac4fbd  

   Tucker, M. A.; Ashall, C.; Shappee, B. J.; Kochanek, C. S.; Stanek, K. Z.; Garnavich, P. (February 2022, The Astrophysical Journal Letters)

   Abstract We present three new spectra of the nearby Type Ia supernova (SN Ia) 2011fe covering ≈480–850 days after maximum light and show that the ejecta undergoes a rapid ionization shift at ∼500 days after explosion. The prominent Feiiiemission lines at ≈4600 Å are replaced with Fei+Feiiblends at ∼4400 Å and ∼5400 Å. The ≈7300 Å feature, which is produced by [Feii]+[Niii] at ≲400 days after explosion, is replaced by broad (≈±15,000 km s⁻¹) symmetric [Caii] emission. Models predict this ionization transition occurring ∼100 days later than what is observed, which we attribute to clumping in the ejecta. Finally, we use the nebular-phase spectra to test several proposed progenitor scenarios for SN 2011fe. Nondetections of H and He exclude nearby nondegenerate companions, [Oi] nondetections disfavor the violent merger of two white dwarfs, and the symmetric emission-line profiles favor a symmetric explosion. 

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2. Enzymatic Benzofuranoindoline Formation in the Biosynthesis of the Strained Bridgehead Bicyclic Dipeptide (+)‐Azonazine A

   https://doi.org/10.1002/anie.202311266  

   Liu, Mengting; Ohashi, Masao; Zhou, Qingyang; Sanders, Jacob N.; McCauley, Erin P.; Crews, Phillip; Houk, K. N.; Tang, Yi (August 2023, Angewandte Chemie International Edition)

   Abstract We uncovered and reconstituted a concise biosynthetic pathway of the strained dipeptide (+)‐azonazine A from marine‐derivedAspergillus insulicola. Formation of the hexacyclic benzofuranoindoline ring system from cyclo‐(l‐Trp‐N‐methyl‐l‐Tyr) is catalyzed by a P450 enzyme through an oxidative cyclization. Supplementing the producing strain with various indole‐substituted tryptophan derivatives resulted in the generation of a series of azonazine A analogs. 

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3. Boltz-1: Democratizing Biomolecular Interaction Modeling

   https://doi.org/10.1101/2024.11.19.624167  

   Wohlwend, Jeremy; Corso, Gabriele; Passaro, Saro; Reveiz, Mateo; Leidal, Ken; Swiderski, Wojtek; Portnoi, Tally; Chinn, Itamar; Silterra, Jacob; Jaakkola, Tommi; et al (November 2024, bioRxiv)

   Abstract Understanding biomolecular interactions is fundamental to advancing fields like drug discovery and protein design. In this paper, we introduce Boltz-1, an open-source deep learning model incorporating innovations in model architecture, speed optimization, and data processing achieving AlphaFold3-level accuracy in predicting the 3D structures of biomolecular complexes. Boltz-1 demonstrates a performance on-par with state-of-the-art commercial models on a range of diverse benchmarks, setting a new benchmark for commercially accessible tools in structural biology. By releasing the training and inference code, model weights, datasets, and benchmarks under the MIT open license, we aim to foster global collaboration, accelerate discoveries, and provide a robust platform for advancing biomolecular modeling. 

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4. Investigating the [C ii]-to-H i Conversion Factor and the H i Gas Budget of Galaxies at z ≈ 6 with Hydrodynamic Simulations

   https://doi.org/10.3847/2041-8213/ac982c  

   Vizgan, David; Heintz, Kasper E.; Greve, Thomas R.; Narayanan, Desika; Davé, Romeel; Olsen, Karen P.; Popping, Gergö; Watson, Darach (October 2022, The Astrophysical Journal Letters)

   Abstract One of the most fundamental baryonic matter components of galaxies is the neutral atomic hydrogen (Hi). At low redshifts, this component can be traced directly through the 21 cm transition, but to infer the Higas content of the most distant galaxies, a viable tracer is needed. We here investigate the fidelity of the fine-structure transition of the (²P_3/2−²P_1/3) transition of singly ionized carbon Ciiat 158μm as a proxy for Hiin a set simulated galaxies atz≈ 6, following the work by Heintz et al. We select 11,125 star-forming galaxies from thesimbasimulations, with far-infrared line emissions postprocessed and modeled within the Sigameframework. We find a strong connection between Ciiand Hi, with the relation between this Cii-to-Hirelation (β_[CII]) being anticorrelated with the gas-phase metallicity of the simulated galaxies. We further use these simulations to make predictions for the total baryonic matter content of galaxies atz≈ 6, and specifically the Higas mass fraction. We find mean values ofM_{H I}/M_⋆= 1.4 andM_{H I}/M_bar,tot= 0.45. These results provide strong evidence for Hibeing the dominant baryonic matter component by mass in galaxies atz≈ 6. 

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5. Decoupling Activity and Specificity in Coronazymes

   https://doi.org/10.1002/smll.202500783  

   Ji, Jiahao; Zuo, Li; Pokhrel, Bishal; Pokhrel, Pravin; Shakya, Sajan; Shen, Hao; Mao, Hanbin (March 2025, Small)

   Abstract Specificity and activity are often at odds for natural enzymes. In this work, specificity and activity in coronazymes made of an Au nanoparticle (AuNP) and coated with DNA aptamer for glucose substrates are decoupled. By single‐molecule fluorescent MT‐HILO (magnetic tweezers coupled with highly inclined and laminated optical sheet) microscopy, it is found that this coronazyme has ≈30 times higher activity on thed‐glucose compared to bare AuNP nanozymes. Significantly, the new coronazyme demonstrates long‐range modulations by circularly polarized light (CPL) according to the matching chirality between the CPL and DNA corona, which follows the rule of chiral induced spin selectivity (CISS). Although the aptamer in the coronazyme is evolved againstd‐glucose, surprisingly, this coronazyme catalyzesl‐glucose better thand‐glucose, likely due to the faster rates for the aptamer to interact with thel‐ overd‐glucose. These results demonstrate, for the first time, an artificial enzyme with its catalytic activity controlled by short‐range intermolecular forces, whereas its chiral specificity is modulated by long‐range CPLs. This decoupled arrangement is pivotal to forge premier catalysts with activity and specificity superior to natural enzymes by separately optimizing these two properties. 

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