@article{20098,
  abstract     = {Climate change is causing wildfires to become more frequent and intense. While predicting burned areas using bioclimatic and anthropogenic factors is an active research area, few studies have examined what drives the economic damages of wildfires. Our study aims to fill this gap by analyzing key factors influencing global economic wildfire damages and projecting future damages under three shared socioeconomic pathways (SSPs). We apply regression analyses to identify significant predictors of economic wildfire damages at country levels and use the fitted model to project future damages under SSP126, SSP245, and SSP370. Results show that the human vulnerability index (HVI), reflecting socioeconomic conditions, is the strongest predictor of historical wildfire damages, followed by water vapor pressure deficit during the fire season and population density around forested areas. We found high population density to be associated with lower damages. These findings contrast with studies of burned areas, where climate factors are more dominant. Our model projects that by 2070, average global economic wildfire damages will be three times higher under SSP370 than SSP126. Our model also shows that following SSP126 not only reduces wildfire damages but also lessens the inequalities in damage distribution across countries. This pathway’s dual focus on equitable socioeconomic progress and climate action potentially enhances a country’s resilience that helps mitigate wildfire damages. Our analyses also indicate that strong socioeconomic development can offset wildfire damages associated with climate hazards, although this is less certain under SSP370. SSP126’s integrated approach improves both socioeconomic conditions and limits global warming, providing substantial benefits to less developed countries while still reducing damages in developed nations, despite their already low HVI scores. Our work complements existing research on burned areas and underscores the importance of sustainable development and international collaboration in reducing the economic damages of wildfires.},
  author       = {Hwong, Yi-Ling and Byers, Edward and Werning, Michaela and Quilcaille, Yann},
  issn         = {2752-5295},
  journal      = {Environmental Research: Climate},
  number       = {3},
  publisher    = {IOP Publishing},
  title        = {{Sustainable development key to limiting climate change-driven wildfire damages}},
  doi          = {10.1088/2752-5295/adec11},
  volume       = {4},
  year         = {2025},
}

@article{20099,
  abstract     = {The hippocampus, critical for learning and memory, is dogmatically described as a trisynaptic circuit where dentate gyrus granule cells (GCs), CA3 pyramidal neurons (PNs), and CA1 PNs are serially connected. However, CA3 also forms an autoassociative network, and its PNs have diverse morphologies, intrinsic properties, and GC input levels. How PN subtypes compose this recurrent network is unknown. To determine the synaptic arrangement of identified CA3 PNs, we combine multicellular patch-clamp recording and post hoc morphological analysis in mouse hippocampal slices. PNs can be divided into distinct “superficial” and “deep” subclasses, the latter including previously reported “athorny” cells. Subclasses have distinct input-output transformations and asymmetric connectivity, which is more abundant from superficial to deep PNs, splitting CA3 locally into two parallel recurrent networks. Coincident spontaneous inhibition occurs frequently within but not between subclasses, implying subclass-specific inhibitory innervation. Our results suggest two separately controlled sublayers for parallel information processing in hippocampal CA3.},
  author       = {Watson, Jake and Vargas Barroso, Victor M and Jonas, Peter M},
  issn         = {2211-1247},
  journal      = {Cell Reports},
  number       = {8},
  publisher    = {Elsevier},
  title        = {{Cell-specific wiring routes information flow through hippocampal CA3}},
  doi          = {10.1016/j.celrep.2025.116080},
  volume       = {44},
  year         = {2025},
}

@article{20100,
  abstract     = {A key step in protein structure prediction involves the detection of co-evolving pairs of residues, a signal for spatial proximity. This information is gleaned from multiple sequence alignment and underscores Alphafold’s structure prediction for almost every known protein. A simple means to create proteins beyond those found in nature, is by unnaturally fusing together two known proteins or protein parts. Here we demonstrate that structured peptides are predicted with significantly reduced accuracy when added to the terminal ends of scaffold proteins. Appending the multiple sequence alignment for the individual peptide tags to that of the scaffold protein often restores prediction accuracy. This work suggests that this windowed multiple sequence alignment approach can be a useful tool for predicting the structure of fused, chimeric proteins.},
  author       = {Vedula, Sanketh and Bronstein, Alexander and Marx, Ailie},
  issn         = {2001-0370},
  journal      = {Computational and Structural Biotechnology Journal},
  pages        = {3292--3298},
  publisher    = {Elsevier},
  title        = {{Improving prediction accuracy in chimeric proteins with windowed multiple sequence alignment}},
  doi          = {10.1016/j.csbj.2025.07.039},
  volume       = {27},
  year         = {2025},
}

@article{20102,
  abstract     = {Speciation is rarely observable directly. A way forward is to compare pairs of ecotypes that evolved in parallel in similar contexts but have reached different degrees of reproductive isolation. Such comparisons are possible in the marine snail Littorina saxatilis by contrasting barriers to gene flow between parallel ecotypes in Spain and Sweden. In both countries, divergent ecotypes have evolved to withstand either crab predation or wave action. Here, we explore transects spanning contact zones between the Crab and the Wave ecotypes using low-coverage whole-genome sequencing, morphological and behavioural traits. Despite parallel phenotypic divergence, distinct patterns of differentiation between the ecotypes emerged: a continuous cline in Sweden indicating a weak barrier to gene flow, but two highly genetically and phenotypically divergent, and partly spatially overlapping clusters in Spain suggesting a much stronger barrier to gene flow. The absence of Spanish early-generation hybrids supported strong isolation, but a low level of gene flow is evident from molecular data. In both countries, highly differentiated loci were located in both shared and country-specific chromosomal inversions but were also present in collinear regions. Despite being considered the same species and showing similar levels of phenotypic divergence, the Spanish ecotypes are much closer to full reproductive isolation than the Swedish ones. Barriers to gene flow of very different strengths between ecotypes within the same species might be explained by dissimilarities in the spatial arrangement of habitats, the selection gradients or the ages of the systems.},
  author       = {Raffini, Francesca and De Jode, Aurélien and Johannesson, Kerstin and Faria, Rui and Zagrodzka, Zuzanna B. and Westram, Anja M and Galindo, Juan and Rolán-Alvarez, Emilio and Butlin, Roger K.},
  issn         = {1365-294X},
  journal      = {Molecular Ecology},
  number       = {21},
  publisher    = {Wiley},
  title        = {{Phenotypic divergence and genomic architecture between parallel ecotypes at two different points on the speciation continuum in a marine snail}},
  doi          = {10.1111/mec.70025},
  volume       = {34},
  year         = {2025},
}

@misc{20103,
  abstract     = {Official implementation, windowed MSAs, and the predictions as reported in the manuscript titled "Improving Prediction Accuracy in Chimeric Proteins with Windowed Multiple Sequence Alignment". (2025-06-27)},
  author       = {Vedula, Sanketh and Bronstein, Alexander and Marx, Ailie},
  publisher    = {Harvard Dataverse},
  title        = {{Replication Data for: "Improving Prediction Accuracy in Chimeric Proteins with Windowed Multiple Sequence Alignment"}},
  doi          = {10.7910/DVN/DYEBVM},
  year         = {2025},
}

@misc{20107,
  abstract     = {This repository contains the data and scripts required to reproduce the results of the manuscript "Sustainable Development Key to Limiting Climate Change-Driven Wildfire Damages" submitted to the Environmental Research Climate Journal (ERCL). },
  author       = {Hwong, Yi-Ling and Byers, Edward and Werning, Michaela and Quilcaille, Yann},
  publisher    = {Zenodo},
  title        = {{Data - Sustainable Development Key to Limiting Climate Change-Driven Wildfire Damages}},
  doi          = {10.5281/ZENODO.13988679},
  year         = {2025},
}

@article{20116,
  abstract     = {Auxin regulates various aspects of plant growth and development by modulating the transcription of target genes through the degradation of auxin/indole-3-acetic acid (Aux/IAA) repressors via the 26S proteasome. Proteasome regulator 1 (PTRE1), a positive regulator of proteasome activity, has been implicated in auxin-mediated proteasome suppression; however, the mechanism by which auxin modulates PTRE1 function remains unclear. Here, we demonstrate that auxin promotes the interaction between germin-like protein 1 (GLP1) and PTRE1, facilitating PTRE1 retention at the plasma membrane. The relocation of PTRE1 results in reduced nuclear 26S proteasome activity, and thus the attenuated Aux/IAA degradation and altered Aux/IAA homeostasis, ultimately resulting in suppressed auxin-mediated transcriptional regulation. Our findings uncover a previously uncharacterized regulatory axis in auxin signaling that controls Aux/IAA protein stability, functioning alongside the TIR1- and TRANSMEMBRANE KINASE 1 (TMK1)-mediated pathways, and highlight the coordination of auxin signaling from the cell surface to the nucleus via auxin-induced PTRE1 relocation, which fine-tunes Aux/IAA protein homeostasis and auxin responses.},
  author       = {Xu, Faqing and Yu, Yongqiang and Guan, Bin and Xu, Tongda and Xu, Zhihong and Xue, Hongwei},
  issn         = {2211-1247},
  journal      = {Cell Reports},
  number       = {8},
  publisher    = {Elsevier},
  title        = {{Germin-like protein 1 interacts with proteasome regulator 1 to regulate auxin signaling by controlling Aux/IAA homeostasis}},
  doi          = {10.1016/j.celrep.2025.116056},
  volume       = {44},
  year         = {2025},
}

@article{20143,
  abstract     = {Bacteria and archaea deploy diverse antiviral defense systems, many of which remain mechanistically uncharacterized. Here, we characterize Kiwa, a widespread two-component system composed of the transmembrane sensor KwaA and the DNA-binding effector KwaB. Cryogenic electron microscopy (cryo-EM) analysis reveals that KwaA and KwaB assemble into a large, membrane-associated supercomplex. Upon phage binding, KwaA senses infection at the membrane, leading to KwaB binding of ejected phage DNA and inhibition of replication and late transcription, without inducing host cell death. Although KwaB can bind DNA independently, its antiviral activity requires association with KwaA, suggesting spatial or conformational regulation. We show that the phage-encoded DNA-mimic protein Gam directly binds and inhibits KwaB but that co-expression with the Gam-targeted RecBCD system restores protection by Kiwa. Our findings support a model in which Kiwa coordinates membrane-associated detection of phage infection with downstream DNA binding by its effector, forming a spatially coordinated antiviral mechanism.},
  author       = {Zhang, Zhiying and Todeschini, Thomas C. and Wu, Yi and Kogay, Roman and Naji, Ameena and Cardenas Rodriguez, Joaquin and Mondi, Rupavidhya and Kaganovich, Daniel and Taylor, David W. and Bravo, Jack Peter Kelly and Teplova, Marianna and Amen, Triana and Koonin, Eugene and Patel, Dinshaw J. and Nobrega, Franklin L.},
  issn         = {1097-4172},
  journal      = {Cell},
  number       = {21},
  pages        = {5862--5877.e23},
  publisher    = {Elsevier},
  title        = {{Kiwa is a membrane-embedded defense supercomplex activated at phage attachment sites}},
  doi          = {10.1016/j.cell.2025.07.002},
  volume       = {188},
  year         = {2025},
}

@phdthesis{20149,
  abstract     = {Immune responses depend on the coordinated and efficient migration of leukocytes. These
cells, which are embedded and tightly confined within tissues, must navigate and traverse
diverse and complex three-dimensional environments. Leukocytes adapt their locomotory
behavior to the mechanical, geometrical, and biochemical characteristics of their
surroundings. In low-density environments, where the pore size of the interstitial matrix
allows free passage, these cells position the nucleus directly behind the lamellipodium, the
protrusive actin structure that forms the leading front of the cell. In this configuration, they
use the nucleus as a gauge to identify the path of least resistance.
Here, we show that in high-density environments, where the pore size precludes free passage
of the cell body, leukocytes reposition the microtubule-organizing center (MTOC) and
associated organelles in front of the nucleus. In this configuration, they use actin structures
protruding orthogonally to the direction of migration in order to open a path for the cell body.
We identify two distinct actin populations that serve this purpose at different subcellular
localizations. At the leading edge, local indentation of the plasma membrane leads to
recruitment of the Wiskott-Aldrich syndrome protein (WASp), which, via Arp2/3, results in
the formation of individual actin foci. At the cell body, actin polymerization is triggered by
DOCK8, a Cdc42 exchange factor, resulting in the formation of a central actin pool.
We demonstrate that the central and peripheral actin pools are functionally communicating
and that depletion of the central actin pool leads to increased actin accumulation at the cell
front, resulting in excessive extension of the leading edge.},
  author       = {Dos Reis Rodrigues, Patricia},
  issn         = {2663-337X},
  pages        = {114},
  publisher    = {Institute of Science and Technology Austria},
  title        = {{Coordination of protrusive forces in immune cell migration }},
  doi          = {10.15479/AT-ISTA-20149},
  year         = {2025},
}

@article{20154,
  abstract     = {In long-lived mammals, including humans, brain cell homeostasis is critical for maintaining brain function throughout life. Most neurons are generated during development and must maintain their cellular identity and plasticity to preserve brain function. Although extensive studies indicate the importance of recycling and regenerating cellular molecules to maintain cellular homeostasis, recent evidence has shown that some proteins and RNAs do not turn over for months and even years. We propose that these long-lived cellular molecules may be the basis for maintaining brain function in the long term, but also a potential convergent target of brain aging. We highlight key discoveries and challenges, and propose potential directions to unravel the mystery of brain cell longevity.},
  author       = {Hetzer, Martin W and Toda, Tomohisa},
  issn         = {1878-108X},
  journal      = {Trends in Neurosciences},
  number       = {9},
  pages        = {645--654},
  publisher    = {Elsevier},
  title        = {{Long-lived cellular molecules in the brain}},
  doi          = {10.1016/j.tins.2025.07.004},
  volume       = {48},
  year         = {2025},
}

@article{20155,
  abstract     = {We study time averages for the norm of solutions to kinetic Fokker–Planck equations associated with general Hamiltonians. We provide fully explicit and constructive decay estimates for systems subject to a confining potential, allowing fat-tail, subexponential and (super-)exponential local equilibria, which also include the classic Maxwellian case. The key step in our estimates is a modified Poincaré inequality, obtained via a Lions–Poincaré inequality and an averaging lemma.},
  author       = {Brigati, Giovanni and Stoltz, Gabriel},
  issn         = {1095-7154},
  journal      = {SIAM Journal on Mathematical Analysis},
  number       = {4},
  pages        = {3587--3622},
  publisher    = {Society for Industrial and Applied Mathematics},
  title        = {{How to construct explicit decay rates for kinetic Fokker–Planck equations?}},
  doi          = {10.1137/24M1700351},
  volume       = {57},
  year         = {2025},
}

@article{20182,
  abstract     = {Sex chromosomes have evolved many times throughout the tree of life, and understanding what has shaped their unusual morphological, sequence, and regulatory features has been a long-standing goal. Most early insights into insect sex chromosome biology came from a few model species, such as the fruit fly Drosophila melanogaster, which limited broad-scale evolutionary inferences. More recently, extensive comparative genomics studies have uncovered several unexpected patterns, which we highlight in this review. First, we describe the conservation of the ancestral X chromosome over 450 million years but also its recurrent turnover (i.e. its reversal to an autosome when a new X chromosome arose) in at least one order. We then summarize classical and more recent findings on how insects modulate the expression of X-linked genes following the degradation of the Y chromosome and how the diverse mechanisms of dosage compensation identified may elucidate important principles of sex chromosome regulatory evolution.},
  author       = {Toups, Melissa A and Vicoso, Beatriz},
  issn         = {2214-5753},
  journal      = {Current Opinion in Insect Science},
  publisher    = {Elsevier},
  title        = {{Insect sex chromosome evolution: Conservation, turnover, and mechanisms of dosage compensation}},
  doi          = {10.1016/j.cois.2025.101411},
  volume       = {72},
  year         = {2025},
}

@article{20183,
  abstract     = {The unequal segregation of organelles has been proposed to be an intrinsic mechanism that contributes to cell fate divergence during asymmetric cell division; however, in vivo evidence is sparse. Using super-resolution microscopy, we analysed the segregation of organelles during the division of the neuroblast QL.p in C. elegans larvae. QL.p divides to generate a daughter that survives, QL.pa, and a daughter that dies, QL.pp. We found that mitochondria segregate unequally by density and morphology and that this is dependent on mitochondrial dynamics. Furthermore, we found that mitochondrial density in QL.pp correlates with the time it takes QL.pp to die. We propose that low mitochondrial density in QL.pp promotes the cell death fate and ensures that QL.pp dies in a highly reproducible and timely manner. Our results provide in vivo evidence that the unequal segregation of mitochondria can contribute to cell fate divergence during asymmetric cell division in a developing animal.},
  author       = {Segos, Ioannis and Van Eeckhoven, Jens and Berger, Simon and Mishra, Nikhil and Lambie, Eric J. and Conradt, Barbara},
  issn         = {2041-1723},
  journal      = {Nature Communications},
  publisher    = {Springer Nature},
  title        = {{Unequal segregation of mitochondria during asymmetric cell division contributes to cell fate divergence in sister cells in vivo}},
  doi          = {10.1038/s41467-025-62484-5},
  volume       = {16},
  year         = {2025},
}

@article{20184,
  abstract     = {Specialized DNA polymerases facilitate various cellular processes. Despite extensive research, the mutagenic effects of these error-prone enzymes on genomes are not fully understood. Here we show that Pol IV promotes genomic instability in Pseudomonas aeruginosa by misincorporating oxidized guanine nucleotides. This activity led to a distinctive mutational signature, characterized by A-to-C transversions occurring preferentially at AT sites flanked by a 5’G and/or 3’C. Furthermore, Pol IV preferentially targeted pathogenicity genes located at specific chromosomal locations near the replication termination region and rRNA-encoding operons. Half of the mutation events catalyzed by Pol IV impaired gene function. This can be attributed to the bias of Pol IV for mutating codons with its preferred sequence contexts, leading to substitutions to unreactive alanine and glycine residues. Remarkably, mutation signatures identified for Pol IV were found in clinical isolate genomes of P. aeruginosa, providing compelling evidence for its role in genetic diversification during pathogen adaptation.},
  author       = {Castell, Sofía D. and Fernandez, Consuelo M. and Tumas, Ignacio N. and Margara, Lucía M. and Miserendino, Maria C and Ceschin, Danilo G. and Pezza, Roberto J. and Monti, Mariela R.},
  issn         = {2399-3642},
  journal      = {Communications Biology},
  publisher    = {Springer Nature},
  title        = {{The low-fidelity DNA Pol IV accelerates evolution of pathogenicity genes in Pseudomonas aeruginosa}},
  doi          = {10.1038/s42003-025-08589-5},
  volume       = {8},
  year         = {2025},
}

@article{20185,
  abstract     = {We show a local rigidity result for the integrability of symplectic billiards. We prove that any domain which is close to an ellipse, and for which the symplectic billiard map is rationally integrable must be an ellipse as well. This is in spirit of the result of [2] for Birkhoff billiards.},
  author       = {Tsodikovich, Daniel},
  issn         = {1050-6926},
  journal      = {Journal of Geometric Analysis},
  number       = {10},
  publisher    = {Springer Nature},
  title        = {{Local rigidity for symplectic billiards}},
  doi          = {10.1007/s12220-025-02148-4},
  volume       = {35},
  year         = {2025},
}

@article{20186,
  abstract     = {Enforcement of information-flow policies has been extensively studied by language-based approaches over the past few decades. In this paper, we propose an alternative, novel, general, and effective approach using enforcement of hyperproperties– a powerful formalism for expressing and reasoning about a wide range of information-flow security policies. We study black- vs. gray- vs. white-box enforcement of hyperproperties expressed by nondeterministic finite-word hyperautomata (NFH), where the enforcer has null, some, or complete information about the implementation of the system under scrutiny. Given an NFH, in order to generate a runtime enforcer, we reduce the problem to controller synthesis for hyperproperties and subsequently to the satisfiability problem for quantified Boolean formulas (QBFs). The resulting enforcers are transferable with low-overhead. We conduct a rich set of case studies, including information-flow control for JavaScript code, as well as synthesizing obfuscators for control plants.},
  author       = {Hsu, Tzu Han and Oliveira Da Costa, Ana A and Wintenberg, Andrew and Bartocci, Ezio and Bonakdarpour, Borzoo},
  issn         = {1432-0525},
  journal      = {Acta Informatica},
  number       = {3},
  publisher    = {Springer Nature},
  title        = {{Gray-box runtime enforcement of hyperproperties}},
  doi          = {10.1007/s00236-025-00502-1},
  volume       = {62},
  year         = {2025},
}

@article{20187,
  abstract     = {Very long-chain fatty acids (VLCFAs), being constituents of different types of lipids, are critical factors in plant development, presumably due to their impact on the endomembrane system. The VLCFAs are synthesized in the endoplasmic reticulum by a heterotetrameric enzymatic complex including β-ketoacyl CoA reductase 1 (KCR1), whose mutant is lethal. Here, we describe the ectopic shoot meristems (esm) mutant, a viable kcr1 allele presumably affecting surface properties of the KCR1 protein. This kcr1-2 mutant shows reduced fatty acyl elongation that impacts VLCFAs. The kcr1-2 plants show severe defects during different stages of development, which all correlate with defects in polar localization and subcellular trafficking of PIN auxin transporters and resulting asymmetric auxin distribution. Detailed analysis of KCR1 expression and patterning defects in kcr1-2 suggests that KCR1 plays a role in delineating boundaries around meristematic and specialized differentiating tissues, including root and shoot meristems, initiating lateral roots, lateral root primordia, and trichomes. In these contexts, KCR1-produced VLCFAs may act in a non-cell-autonomous manner. Viable kcr1-2 represents a useful tool to study VLCFA roles in plant development and highlights VLCFAs as critical developmental factors at the interface of cell polarity and tissue development.},
  author       = {Babic, David and Abualia, Rashed and Fiedler, Lukas and Qi, Linlin and Tellier, Frédérique and Smoljan, Adrijana and Rakusova, Hana and Valošek, Petr and Han, Huibin and Benková, Eva and Faure, Jean Denis and Friml, Jiří},
  issn         = {1365-313X},
  journal      = {Plant Journal},
  number       = {3},
  publisher    = {Wiley},
  title        = {{Biosynthesis of very long-chain fatty acids is required for Arabidopsis auxin-mediated embryonic and post-embryonic development}},
  doi          = {10.1111/tpj.70396},
  volume       = {123},
  year         = {2025},
}

@article{20188,
  abstract     = {Collective cell migration is coordinated by the front-to-rear intercellular propagation of EGFR-Ras-ERK pathway activation. However, the molecular mechanisms integrating front-to-rear information into this intercellular signaling cascade, particularly the determinants of cellular front-side specification, remain elusive. We visualized the activity of EGFR, Ras, Rac1 and Rab5A (hereafter Rab5) by using FRET biosensors and chemogenetic tools. Whereas EGFR activation was uniformly observed within cells, Ras activation was biased to the front side within cells. The polarized Ras activation depended on Merlin and Rac1, which also showed front-biased activation. Furthermore, Rab5, a crucial regulator of cell migration, demonstrated similar front-biased activation and was found to function downstream of Ras while being necessary for Rac1 activation. Thus, the positive feedback loop consisting of Ras, Rab5 and Rac1 is activated primarily at the front of collectively migrating cells. These findings offer new spatio-temporal insight into processing front–rear information during collective cell migration.},
  author       = {Jikko, Yuya and Deguchi, Eriko and Matsuda, Kimiya and Hino, Naoya and Tsukiji, Shinya and Matsuda, Michiyuki and Terai, Kenta},
  issn         = {1477-9137},
  journal      = {Journal of Cell Science},
  number       = {15},
  publisher    = {The Company of Biologists},
  title        = {{Front-biased activation of the Ras-Rab5-Rac1 loop coordinates collective cell migration}},
  doi          = {10.1242/jcs.263779},
  volume       = {138},
  year         = {2025},
}

@inproceedings{20189,
  abstract     = {Certification was made mandatory for the first time in the latest hardware model checking competition. In this case study, we investigate the trade-offs of requiring certificates for both passing and failing properties in the competition. Our evaluation shows that participating model checkers were able to produce compact, correct certificates that could be verified with minimal overhead. Furthermore, the certifying winner of the competition outperforms the previous non-certifying state-of-the-art model checker, demonstrating that certification can be adopted without compromising model checking efficiency.},
  author       = {Froleyks, Nils and Yu, Zhengqi and Preiner, Mathias and Biere, Armin and Heljanko, Keijo},
  booktitle    = {37th International Conference on Computer Aided Verification},
  isbn         = {9783031986673},
  issn         = {1611-3349},
  location     = {Zagreb, Croatia},
  pages        = {281--295},
  publisher    = {Springer Nature},
  title        = {{Introducing certificates to the hardware model checking competition}},
  doi          = {10.1007/978-3-031-98668-0_14},
  volume       = {15931},
  year         = {2025},
}

@article{20192,
  abstract     = {We study the physical origin and spectroscopic impact of extreme nebular emission in high-redshift galaxies. The nebular continuum, which can appear during an extreme starburst, is of particular importance as it tends to redden UV slopes and has a significant contribution to the UV luminosities of galaxies. Furthermore, its shape can be used to infer the gas density and temperature of the interstellar medium. First, we provide a theoretical background, showing how different stellar populations (SPS models, initial mass functions (IMFs), and stellar temperatures) and nebular conditions impact observed galaxy spectra. We demonstrate that, for systems with strong nebular continuum emission, 1) UV fluxes can increase by up to 0.7~mag (or more in the case of hot/massive stars) above the stellar continuum, which may help reconcile the surprising abundance of bright high-redshift galaxies and the elevated UV luminosity density at z>10, 2) at high gas densities, UV slopes can redden from \beta<-2.5 to \beta\sim-1, 3) observational measurements of \xi_{\rm ion} are gross underestimates, and 4) UV downturns from two-photon emission can masquerade as damped Ly\alpha systems. Second, we present a dataset of 58 galaxies observed with NIRSpec on JWST at 2.5<z<9.0 that are selected to have strong nebular continuum emission via the detection of the Balmer jump. Five of the 58 spectra are consistent with being dominated by nebular emission, exhibiting both a Balmer jump and a UV downturn consistent with two-photon emission. For some galaxies, this may imply the presence of hot massive stars and a top-heavy IMF. We conclude by exploring the properties of spectroscopically confirmed z>10 galaxies, finding that UV slopes and UV downturns are in some cases redder or steeper than expected from SPS models, which may hint at more exotic (e.g. hotter/more massive stars or AGN) ionizing sources.},
  author       = {Katz, Harley and Cameron, Alex J. and Saxena, Aayush and Barrufet, Laia and Choustikov, Nicholas and Cleri, Nikko J. and De Graaff, Anna and Ellis, Richard S. and Fosbury, Robert A.E. and Heintz, Kasper E. and Maseda, Michael and Matthee, Jorryt J and Mcconachie, Ian and Oesch, Pascal A.},
  issn         = {2565-6120},
  journal      = {The Open Journal of Astrophysics},
  publisher    = {Maynooth Academic Publishing},
  title        = {{21 Balmer Jump Street: The nebular continuum at high redshift and implications for the bright galaxy problem, UV continuum slopes, and early stellar populations}},
  doi          = {10.33232/001c.142570},
  volume       = {8},
  year         = {2025},
}

