@article{23093, abstract = {Land-use change, such as the transformation of woody ecosystems into open pastures, acts as a strong ecological filter, favouring some species while excluding others according to differences in ecological niche breadth. Understanding how differences in niche breadth influence species responses under anthropogenic filters is crucial to anticipate their persistence or displacement. In this study, we quantified realized niche breadth in two sympatric ecosystem engineers, the Neotropical leaf-cutter ants Atta cephalotes and Atta laevigata, to test whether breadth differences are consistent with specialist and generalist ecological strategies. We characterized realized niche breadth across fine-scale environmental gradients by integrating hemispherical photography, microclimatic data, mound architecture, and edaphic profiles from 114 colonies across a regional transect in the Colombian Andes, alongside macroclimatic data from Copernicus. Principal Component Analysis (PCA) and PERMANOVA identified canopy openness and bushes- and tree-type vegetation density as the principal axes of interspecific niche partitioning. The observed differences in realized niche breadth were consistent with specialist and generalist ecological strategies. A. laevigata was predominantly associated with open-canopy areas, warmer micro- and macroclimatic conditions, and narrower edaphic dispersion. In contrast, A. cephalotes occupied a wider range of microhabitat conditions. This broader realized niche breadth is compatible with previous reports of A. cephalotes occurring in urban areas. Together, these findings suggest that niche breadth may influence how Neotropical leaf-cutter ants respond to habitat transformation, helping to understand the ecological consequences of land-use change.}, author = {Garcia Castillo, Diego Fernando}, issn = {1932-6203}, journal = {Plos One}, number = {10}, pages = {e0351518}, publisher = {Public Library of Science}, title = {{Generalism vs. specialization: Does niche breadth influence species responses to anthropogenic land-use change in Neotropical leaf-cutter ants?}}, doi = {10.1371/journal.pone.0351518}, volume = {21}, year = {2026}, } @article{23089, abstract = {The location of the hydrogen-helium (H/He) immiscibility boundary controls whether and where helium rain occurs in giant planets, yet it remains uncertain because high-pressure experiments are challenging and ab initio simulations are limited in system size and simulation time. We map this boundary by computing composition-dependent chemical potentials from large-scale molecular dynamics driven by machine learning potentials trained on three density functional approximations (PBE, vdW-DF, and the hybrid HSE). Across the pressure range of 100-1000 GPa, the demixing temperatures are typically ~ 2000 K lower than previous ab initio simulations using small system sizes, and this discrepancy is larger than the estimated error from the chosen density functionals, machine learning potentials, neglect of nuclear quantum effects, and statistical uncertainties. Fitting the H/He mixing free energy to a Redlich-Kister regular solution model rationalizes the thermodynamic driving force for phase separation, and provides a predictive representation of the boundary. Comparing with current planetary interior profiles indicates that helium rain is plausible in Saturn but unlikely in the warmer interior of Jupiter. Our results narrow the uncertainty in the H/He immiscibility boundary and provide inputs for planetary models that couple demixing, heat transport, and composition gradients in gas giants.}, author = {Wang, Xiaoyu and Hamel, Sebastien and Cheng, Bingqing}, issn = {2041-1723}, journal = {Nature Communications}, publisher = {Springer Nature}, title = {{Hydrogen-helium immiscibility boundary in gas-giant planetary interiors from machine-learning molecular dynamics}}, doi = {10.1038/s41467-026-77117-8}, volume = {17}, year = {2026}, } @article{23090, abstract = {Homologous recombination is ubiquitous across evolution, generating variation through genetic reshuffling. Although bacteria lack meiotic recombination, homologous recombination has been known to extensively shape their genomes. However, the mechanisms and ecological conditions sustaining frequent recombination in bacteria remain unclear. Using an Escherichia coli–P1 phage model system, we reveal how frequent recombination emerges from CRISPR-based herd immunity to a generalized transducing phage (DNA vector). Herd immunity maintains phage-susceptible donor bacteria, recipient immune bacteria, and transducing phage, which promotes chromosomal gene flow that exceeds spontaneous mutation by up to two orders of magnitude. Notably, recombination begins as bacterial cultures enter stationary phase, when canonical mutation supply through population growth and DNA replication is strongly reduced, and recombination can be reinitiated by brief fresh nutrient pulses. Genetic analysis showed that stationary-phase recombination requires recA, recB, and recG, connecting this process to a defined homologous recombination pathway, and suggests a plausible transcriptional regulatory link to transition to nutrient limitation. Bacterial herd immunity therefore has an unexpected evolutionary consequence: it can promote homologous recombination by turning phages into de facto pollinators. This mechanism can help explain how high rates of homologous recombination may be sustained across bacterial populations and suggests that bacterial immune systems can shape molecular evolution not only by blocking infection but also by regulating genetic exchange.}, author = {Payne, Pavel and Plevka, Pavel and Bollback, Jonathan P and Guet, Calin C}, issn = {1537-1719}, journal = {Molecular Biology and Evolution}, keywords = {homologous recombination, defense systems, CRISPR-Cas, herd immunity, stationary phase, bacterial evolution}, number = {10}, publisher = {Oxford University Press}, title = {{Herd immunity underlies homologous recombination in stationary phase bacteria}}, doi = {10.1093/molbev/msag238}, volume = {43}, year = {2026}, } @article{23088, abstract = {In this review, we provide an engineering assessment of prevalent blood-wetted cardiovascular devices, their hematologic complications, and their interconnections to identify key areas for future research. In fact, the incidence of cardiovascular diseases has promoted the development of various devices to treat these conditions, including mechanical circulatory supports (mechanical pumps that assist or replace failing hearts), artificial valves to replace faulty heart valves, stents to relieve obstructions in blood vessels, vascular grafts to repair/reconstruct damaged vessels, patches to reinforce or reconstruct cardiovascular tissues, and other implants. The hemocompatibility of these cardiovascular devices, namely their ability to interact with blood flow without causing adverse reactions, remains unsatisfactory, and recurrent complications include thrombosis, hemolysis, and bleeding. Therefore, the discussion provided herein will support readers approaching cardiovascular technologies in building a solid foundation and provide everyone with an up-to-date overview of ongoing research in this multidisciplinary field.}, author = {Padovani, Damiano and Afsharimani, Nasima S and Cioncolini, Andrea and Ding, Yu}, issn = {2731-3395}, journal = {Communications Engineering}, publisher = {Springer Nature}, title = {{Hematologic complications and design challenges in cardiovascular devices}}, doi = {10.1038/s44172-026-00771-9}, volume = {5}, year = {2026}, } @phdthesis{23072, abstract = {Inferring signal from large quantities of data is one of the most important problems in today’s world, with neural networks emerging as the most powerful solution. While there have been massive breakthroughs in the ML space, there are two main drawbacks. The first is that most of these models are “black boxes”, with very little understanding of why they work, which makes it hard to find the correct architecture for a given problem. The architecture is crucial, as the widely used training algorithms are “local” and thus rely on the loss landscape being benign enough to find a global optimum. This brings us to the second problem: while there is a lot of evidence that this can be overcome with large enough data, this is less clear for datasets which are noisy, do not have enough samples, or have a non-standard structure. Historically, on a smaller scale, the alternative has been simple (Bayesian) statistical methods, which also have the advantage of being interpretable and adaptable. However, many of the classical results cannot be easily extended to the high-dimensional regime in which modern data lives. In this work we want to consider two different settings relating to the above. The first is approximate message passing (AMP), an iterative algorithm for high-dimensional (generalized) linear models that easily lends itself to Bayesian setups, and which in many cases is provably Bayes-optimal. The second is an autoencoder with a shallow encoder, for which we can analyze the weights along the training trajectory of gradient descent. Surprisingly, we will find a connection between the two, as we recover certain structures of AMP. We will first introduce the AMP framework by studying an extension that can be applied to a wider variety of data: rotationally invariant generalized approximate message passing (RI-GAMP). This shows that one can extend the AMP framework to a much wider class of algorithms, relevant to more practical settings. The results are then also confirmed on real data that go beyond the theoretical setting. We then move to the setup of an autoencoder with a shallow encoder and a Bayesian prior in the high-dimensional regime, in which the input and compression dimensions are large and proportional; this is also a first step towards opening one of the black boxes above, as we can say precisely when and why the network works. While autoencoders are widely used in modern ML architectures, most fundamental research in this direction has focused on extreme asymptotic regimes, where the autoencoder is either severely over- or under-parameterized, and which do not extend to the proportional high-dimensional regime. We show that for Gaussian priors the network finds the global optimum, and these theoretical findings extrapolate strikingly well to real image data. Next we extend this analysis to more structured priors and a deeper decoder. For sparse Gaussian inputs in the training regime studied here, the shallow decoder does not exploit sparsity and yields the same dynamics as in the Gaussian setting. We then show how a deeper decoder can break this behavior, and interestingly, if we treat the problem as an AMP problem, the network eventually learns the same decoding as AMP. This too extrapolates to real image data. Lastly, we will show that the AMP setup has real practical use, by using a practical variant, genetic vector approximate message passing (gVAMP), for predicting plasma protein levels from genetic information using the UKB GWAS data. This is a perfect example of the problems in the high-dimensional regime: approximately 8.4 million dimensions and 40,000 samples, where the high noise, low sample count, and large size make it hard for ML methods to work. To get the optimal prediction accuracy we consider a two-step inference. We first consider a pre-processed version of the data, of about 880,000 dimensions, on which we run the gVAMP algorithm; this allows us to find predictive regions, taking into account joint effects between different regions, and for most proteins we end up selecting only about 0.1% of the dimensions. We then consider the analogue of this small subset, on which we can now run a standard tree algorithm (XGB) that no longer suffers from the aforementioned problems. This pipeline yields better prediction accuracy than recent nonlinear deep learning approaches applied to this data, as we are able to handle the pre-processing in a principled Bayesian way.}, author = {Kögler, Kevin}, issn = {2663-337X}, pages = {222}, publisher = {Institute of Science and Technology Austria}, title = {{Compression and inference in high dimensions: An approximate message passing perspective}}, doi = {10.15479/AT-ISTA-23072}, year = {2026}, } @article{23094, abstract = {The formation of C(sp2)–heteroatom bonds through cross-coupling catalysis is central to the synthesis of pharmaceuticals, agrochemicals and materials. Whereas Pd0/PdII catalysis requires substrate-specific ligand optimization to balance the competing demands of oxidative addition and reductive elimination, NiI/NiIII catalysis offers a complementary strategy because the bond-forming step is intrinsically favourable. However, contemporary NiI/NiIII methodologies suffer from insufficient oxidative addition reactivity, restricting the aryl halide scope and requiring high catalyst loadings. Here we show that mechanistically guided ligand design overcomes these limitations. Together with a non-nucleophilic base additive that promotes direct visible-light generation of NiI from a bench-stable NiII precatalyst, this ligand design enables the coupling of electron-rich aryl bromides with N-, O-, S- and P-based nucleophiles at nickel loadings as low as 100 ppm. The method is compatible with sterically encumbered nucleophiles and enables gram-scale synthesis and late-stage functionalization of complex molecules.}, author = {Bena, Aleksander and Banik, Trisha and Giannoudis, Christos and Ortis, Florian and Bím, Daniel and Baunis, Haralds and Palissery, Gayathri and Pieber, Bartholomäus}, issn = {2520-1158}, journal = {Nature Catalysis}, publisher = {Springer Nature}, title = {{Ligand design broadens NiI-catalysed C(sp2)–heteroatom couplings of aryl bromides at low catalyst loadings}}, doi = {10.1038/s41929-026-01616-6}, year = {2026}, } @article{23095, abstract = {The PXP chain was recently shown to exhibit superdiffusive energy transport with Kardar-Parisi-Zhang-like scaling, z ≈ 3/2, joining a growing number of spin chains with this exponent. An understanding of how this anomalous hydrodynamics emerges from microscopics is, however, still lacking. In this work, we show that finite-temperature energy transport in this model provides a window into the emergence of superdiffusion. At finite temperature, the energy autocorrelation function exhibits a crossover from short-time coherent dynamics to long-time hydrodynamics. The short-time behavior is dominated by a single magnon band and can be understood analytically. In momentum space, this regime is characterized by spectral weight near q = π. The damping time τ , which separates the short-time magnon-dominated behavior from the late-time hydrodynamics, grows rapidly upon cooling, consistent with an activated form τ (β) ∼ βeβ with a gap scale set by the magnon band. At longer times, the spectral weight transfers to q = 0 and the running decay exponent drifts toward the superdiffusive value z = 3/2. Finite-temperature energy transport therefore provides a bridge between microscopic magnon physics and late-time superdiffusion in the PXP model.}, author = {Shengtao, Jiang and Desaules, Jean-Yves Marc and Ljubotina, Marko and Scaffidi, Thomas}, issn = {2469-9969}, journal = {Physical Review B}, number = {8}, publisher = {American Physical Society}, title = {{Finite-temperature crossover from coherent magnons to energy superdiffusion in the PXP model}}, doi = {10.1103/mx9k-1mc6}, volume = {114}, year = {2026}, } @article{23115, abstract = {We investigate the association between galaxies and neutral O I absorption systems at z ∼ 6, which trace metalenriched gas during the epoch of reionization. We identify 40 galaxies across six quasar fields, residing in 15 overdensities within 300 kpc of the background sight lines. Five O I absorption systems are associated with five of these overdensities, yielding a covering fraction of 0.27 0.10 +0.13 within 300 kpc. The absorption occurs beyond typical virial radii, indicating that the gas traces extended overdensity environments rather than individual galaxy halos, unlike the z ∼ 0 circumgalactic medium (CGM), which is largely bound to halos. These galaxy-associated absorbers account for ∼35% of all O I systems seen in blind quasar surveys, implying the remainder arise in lower-mass galaxies below our detection threshold or in dense neutral intergalactic medium pockets. The CGM around these galaxies contains ≳ 2 × 106 M⊙ of oxygen, comparable to the interstellar medium oxygen mass of the galaxies themselves, suggesting that the surrounding environment holds as much metal mass as the galaxies. All five galaxy-associated systems show significantly higher log NCII NOI ( / ) ratios than absorbers lacking galaxy associations. Furthermore, relative abundance ratios ([Si/O], [C/O]) reveal that four of the five exhibit enrichment patterns consistent with Population III nucleosynthesis at the outskirts of galaxy overdensities. These rare systems offer a unique window into the role of first-generation stars in shaping the early metal enrichment of galaxies and their environments.}, author = {Higginson, Jack and Bordoloi, Rongmon and Simcoe, Robert A. and Matthee, Jorryt J and Kashino, Daichi and Mackenzie, Ruari and Kramarenko, Ivan and Lilly, Simon J. and Eilers, Anna-Christina and Naidu, Rohan P. and Yue, Minghao}, issn = {1538-4357}, journal = {The Astrophysical Journal}, number = {1}, publisher = {IOP Publishing}, title = {{EIGER. VIII. First stars signatures in the connection between O I absorption and galaxies in the epoch of reionization}}, doi = {10.3847/1538-4357/ae3e81}, volume = {999}, year = {2026}, } @article{23117, abstract = {We present a comprehensive analysis of the relationship between galaxies and the intergalactic medium (IGM) during the late stages of cosmic reionization, based on the complete JWST EIGER dataset. Using deep NIRCam 3.5 μm slitless spectroscopy, we construct a sample of 948 [O iii]λ5008-emitting galaxies with −21.4 ≲ MUV ≲ −17.2 spanning 5.33 < z < 6.97 along six quasar sight lines. We correlate these galaxies with Lyα and Lyβ transmission measured from high-resolution quasar spectra across multiple redshift intervals. We find clear redshift evolution in the correlation between galaxy density and transmission: it is suppressed in overdense regions at z < 5.50, while enhanced at 5.70 < z < 6.15. The intermediate range exhibits a transitional behavior. Cross-correlation measurements further reveal excess absorption within ∼8 cMpc of galaxies at low redshifts, and enhanced transmission at intermediate scales (∼5–20 cMpc) at z > 5.70. Statistical tests using mock catalogs with realistic galaxy clustering but no correlation with the transmission field confirm that the observed correlations are unlikely to arise by chance. The evolving signals can be explained by stronger absorption in overdense regions, combined with the competing influences of local radiation fields and the rising background radiation. While local radiation dominates ionization of the surrounding IGM at earlier times, the background becomes increasingly important, eventually surpassing the impact of nearby galaxies. These results support an inside-out progression of reionization, with ionized regions originating around clustered, star-forming galaxies and gradually extending into underdense regions.}, author = {Kashino, Daichi and Lilly, Simon J. and Matthee, Jorryt J and Mackenzie, Ruari and Eilers, Anna-Christina and Bordoloi, Rongmon and Simcoe, Robert A. and Naidu, Rohan P. and Yue, Minghao and Liu, Bin}, issn = {1538-4357}, journal = {The Astrophysical Journal}, number = {2}, publisher = {IOP Publishing}, title = {{EIGER. VII. The evolving relationship between galaxies and the intergalactic medium in the final stages of reionization}}, doi = {10.3847/1538-4357/ae2799}, volume = {997}, year = {2026}, } @article{23111, abstract = {In single-molecule electronics, 4,4′-bipyridine is a well-characterized molecule that serves both as a fundamental testbed for developing experimental methodologies and showcases the complex behaviors expected from molecular electronic components. In break junction experiments, it is generally understood to exhibit a high- and a low-conductance state that are attributed to a tilted and stretched single-molecule configuration. Despite this established view, we suggest a supramolecular origin for these conductance states that has not previously been considered. Our findings indicate that the high- and low-conductance states may arise from the presence of two molecules and one molecule, respectively, challenging the conventional interpretation. Using a state-of-the-art machine learning force field called the neuroevolution potential, we find that the conventional interpretation of a tilted and stretched configuration is inconsistent with our simulations. Instead, our results suggest that the presence of two molecules promotes junction geometries and gold rearrangements that stabilize a high-conductance state whose transmission exceeds twice that of the low-conductance state. Furthermore, we compare this interpretation to the existing literature of diverse experimental data on 4,4′-bipyridine in break junctions and find that it is consistent with the broader body of experimental evidence. Our results highlight the structural complexity of molecular behavior within break junctions, suggesting even more complex dynamics than originally anticipated. In this light, a broader examination of the dynamics of molecules in single-molecule break junctions with machine learning-assisted molecular dynamics is warranted.}, author = {Bro-Jørgensen, William and Lin, Junfeng and Hamill, Joseph M. and Solomon, Gemma C.}, issn = {2694-2496}, journal = {ACS Nanoscience Au}, number = {4}, pages = {662--673}, publisher = {American Chemical Society}, title = {{Machine learning-enhanced molecular dynamics of 4,4′-bipyridinein a break junction: A supramolecular origin of the high conductance}}, doi = {10.1021/acsnanoscienceau.6c00052}, volume = {6}, year = {2026}, } @article{23116, abstract = {The Legacy Survey of Space and Time (LSST) is expected to observe up to ∼100 million quasars in the next decade. In this work, we show that it is possible to use such data to measure the characteristic frequency evolution of a “chirp” induced by gravitational waves, which can serve as robust evidence for the presence of a compact supermassive black hole binary. Following the LSST specifications, we generate mock lightcurves consisting of (i) a post-Newtonian chirp produced by orbital motion through, e.g., relativistic Doppler boosting, (ii) a damped random walk representing intrinsic quasar variability, and (iii) Gaussian photometric errors, while assuming nonuniform observations with extended gaps over a period of 10 yr. Through a fully Bayesian analysis, we show that we can simultaneously measure the chirp and noise parameters with little degeneracy between the two. For chirp signals with an amplitude of A = 0.5 mag and a range of times to merger (tm = 15–104 yr), we can typically measure a nonzero amplitude and positive frequency derivative with over 5σ credibility. For binaries with tm = 50 yr, we achieve 3σ (5σ) confidence that the signal is chirping for A ≳ 0.1 (A > 0.2). The median runtime of our analysis is 5.6 minutes, with a minimum as low as 35 s, making it scalable to a large number of lightcurves. This implies that LSST could, on its own, establish the presence of a compact supermassive black hole binary, and thus discover gravitational wave sources detectable by LISA and by Pulsar Timing Arrays.}, author = {Xin, Chengcheng and Isi, Maximiliano and Farr, Will M. and Haiman, Zoltán}, issn = {1538-4357}, journal = {The Astrophysical Journal}, number = {1}, publisher = {IOP Publishing}, title = {{Identifying compact chirping SMBHBs in LSST using Bayesian analysis}}, doi = {10.3847/1538-4357/ae40b3}, volume = {999}, year = {2026}, } @article{23096, abstract = {The first generation of stars, known as population III (Pop III), formed from primordial gas consisting solely of hydrogen and helium and is believed to have emerged only a few hundred million years after the Big Bang. Detecting the chemical enrichment of metal-poor circumgalactic gas offers a promising way to trace the enrichment signature of Pop III stars. Along the sight line to the quasar SDSS J0100+2802, a metal absorber at z = 5.945, showing over-abundant carbon and silicon compared with solar, has been reported to be consistent with the enrichment pattern of Pop III stars. Here, using data recorded by the James Webb Space Telescope, we report the discovery of an unusually metal-poor galaxy overdensity of 17 members (mean metallicity ~3% of solar) near this metal absorber, which is ~0.4 dex more metal-poor than coeval galaxies in similarly overdense environments. This less chemically evolved system may have provided favourable conditions for preserving the absorption signatures of Pop III enrichment. We infer a minimum dark matter halo mass of log(Mh,min/M⊙) = 10.68+0.93 −1.72, supporting late-time Pop III formation at the outskirts of atomic hydrogen cooling haloes. Our findings open a promising observational pathway to identifying the chemical imprints of the first stars and constrain the conditions for their formation.}, author = {Li, Zihao and Kakiichi, Koki and Christensen, Lise and Cai, Zheng and D’Odorico, Valentina and Matthee, Jorryt J and Kashino, Daichi and Bordoloi, Rongmon and Mackenzie, Ruari and Berg, Trystyn A.M. and Vanni, Irene and Salvadori, Stefania and Venditti, Alessandra and Zhang, Shiwu and Bosman, Sarah E.I. and Bañados, Eduardo and Davies, Frederick B. and Fan, Xiaohui and Jun, Hyunsung D. and Jin, Xiangyu and Li, Mingyu and Rojas-Ruiz, Sofía and Wang, Feige and Yang, Jinyi and Zou, Siwei and Zhang, Huanian and Zhu, Yongda}, issn = {2397-3366}, journal = {Nature Astronomy}, publisher = {Springer Nature}, title = {{First-star imprints in a metal-poor galaxy overdensity near the end of reionization}}, doi = {10.1038/s41550-026-02993-5}, year = {2026}, } @article{23112, abstract = {We study the joint spectral properties of two coupled random matrices H(1) and H(2), which are either real symmetric or complex Hermitian. The entries of these matrices exhibit polynomially decaying correlations, both within each matrix and between them. Surprisingly, we find that under extremely weak decorrelation condition, permitting H(1) and H(2) to be almost fully correlated, the fluctuations of their individual eigenvalues in the bulk of the spectrum are still asymptotically independent. Furthermore, we demonstrate that this decorrelation condition is optimal.}, author = {Kolupaiev, Oleksii}, issn = {1350-7265}, journal = {Bernoulli}, keywords = {correlated random matrix, eigenvalue perturbation theory, Local law, Wigner-type matrix}, number = {4}, pages = {2999--3023}, publisher = {Bernoulli Society for Mathematical Statistics and Probability}, title = {{Spectral independence of almost fully correlated random matrices}}, doi = {10.3150/26-bej1976}, volume = {32}, year = {2026}, } @article{23060, author = {Ziletti, Chiara}, isbn = {9783702512187}, issn = {1012-0327}, journal = {Scrinium}, location = {Barcelona, Spain}, pages = {181--186}, publisher = {Anton Pustet Verlag}, title = {{International Council on Archives (ICA) Barcelona Congress 2025, 27-30 October 2025}}, volume = {80}, year = {2026}, } @article{23114, author = {Pieber, Bartholomäus and Nijs, Anne}, issn = {1099-0690}, journal = {European Journal of Organic Chemistry}, publisher = {Wiley}, title = {{The EuChemS division of organic chemistry and EurJOC - partners in advancing organic chemistry}}, doi = {10.1002/ejoc.70847}, year = {2026}, } @article{23123, abstract = {How many points can be placed in an 𝑛 × 𝑛 grid sothat every (affine) line contains at most 𝑘 points? Weprove that for 𝑛 ⩾ 𝑘 ⩾ 1037 the maximum number ofpoints is exactly 𝑘𝑛. Our proof builds on the recent workof Kovács, Nagy and Szabó (who proved an analogousresult when 𝑘 is at least about √𝑛 log 𝑛), incorporat-ing ideas of Jain and Pham. Using the same approach,we also obtain new bounds for higher-dimensionalextensions of this problem}, author = {Grebennikov, Aleksandr and Kwan, Matthew Alan}, issn = {1469-2120}, journal = {Bulletin of the London Mathematical Society}, number = {10}, publisher = {Wiley}, title = {{No‐(k+1)‐in‐line problem for large constant k}}, doi = {10.1112/blms.70510}, volume = {58}, year = {2026}, } @article{23121, abstract = {A widespread observation in molecular evolution is that X-linked genes evolve faster—and often adapt faster—than autosomal genes. Three main ideas have been put forward to explain “faster-X” adaptation. The first is that new beneficial mutations are typically partially recessive with respect to fitness, leading to more efficient selection in hemizygous males. The second is that sex differences in recombination, or sex differences in variance in reproductive success, enhance the effective population size on the X chromosome relative to autosomes. Both ideas have limitations: the first conflicts with theories of dominance, in which beneficial mutations are proposed to be partially dominant, while the second only applies to some taxa. Here we tested a third, newly-proposed theory, in which mutations with large “scaled phenotypic effects” (i.e., large effects relative to the distance to a phenotypic optimum) experience more positive selection on the X. Specifically, we used three proxies for scaled phenotypic effects—amino-acid dissimilarity, amino-acid conservation, and gene age—and estimated X and autosomal rates of adaptation of nonsynonymous mutations across effect-size classes. We did this in three lineages with a well-documented faster-X: Drosophila melanogaster, Mus musculus, and Homo sapiens. As expected, we found that large-effect mutations were more likely to be under purifying selection and less likely to be under positive selection than small-effect mutations. However, contrary to the new theory, faster-X adaptation was not enriched among large-effect mutations. Overall, our results highlight an unresolved gap between patterns of sex chromosome evolution and theories of dominance for fitness.}, author = {Ruzicka, Filip and Vicoso, Beatriz}, issn = {1759-6653}, journal = {Genome Biology and Evolution}, keywords = {evolutionary biology, population genetics, sex chromosomes, adaptation, genetic divergence, McDonald-Kreitman test, Fisher’s geometric model}, publisher = {Oxford University Press}, title = {{Is faster-X adaptation due to large-effect mutations? An empirical test of a new theory}}, doi = {10.1093/gbe/evag259}, year = {2026}, } @article{23124, abstract = {Among the set of hypersurfaces of degree d and dimension defined by the vanishing of a homogeneous polynomial with coefficients in the set {−1, +1}, we investigate the probability that a hypersurface contains a rational point as d and tend to ∞.}, author = {Browning, Timothy D and Sawin, Will}, issn = {1464-3847}, journal = {The Quarterly Journal of Mathematics}, publisher = {Oxford University Press}, title = {{Random diophantine equations of large degree}}, doi = {10.1093/qmath/haag037}, year = {2026}, } @phdthesis{22984, author = {Teplova, Anastasiia}, isbn = {978-3-99078-093-0}, issn = {2663-337X }, pages = {190}, publisher = {Institute of Science and Technology Austria}, title = {{Chasing the elusive: Investigating nucleotide cyclase activity in gibberellin and strigolactone signalling; Cellular mechanisms of gravity sensing and response in roots}}, doi = {10.15479/AT-ISTA-22984}, year = {2026}, } @phdthesis{23079, abstract = {We study the computational aspects of the two central solution concepts of stochastic games played on finite graphs for an infinite number of steps: the value in two-player zero-sum games, and Nash equilibria in multi-player games. In both settings, exact solutions are in tractable. Fortwo-playerzero-sumconcurrentstochasticgames,valuescanbeirrational,and the associated decision problem is SQRT-SUM hard. For multi-player turn-based stochastic games,theequilibriumprobabilitiescanbeirrational,anddecidingtheconstrainedexistence of a Nash equilibrium is undecidable in the presence of memory, and ∃R-complete when the players are restricted to stationary strategies. Hence, in both settings, the natural computational problem is the approximation of the solution within an arbitrary additive error. In this thesis, we present improved complexity results and algorithms for such approximation problems. The first part of the thesis considers two-player zero-sum concurrent stochastic games with two classic objectives: (a) stateful-discounted objectives, which are similar to the classic discounted-sum objectives, but states are associated with different discount factors rather than a single discount factor; and (b) parity objectives, which are a canonical representation for ω-regular objectives. For stateful-discounted objectives, given an ordering of the discount factors, the limit value is the limit of the value of the stateful-discounted objectives, as the discount factors approach zero according to the given order. The value-approximation problem is known to be in EXPSPACE for the limit value of stateful-discounted objectives and in PSPACEforparityobjectives,andthebest-knownalgorithmsforbothproblemsareatleast exponential time, with an exponential dependence on the number of states and actions. Our main results for the value-approximation problem for the limit value of stateful-discounted objectives and parity objectives areas follows: (a)we establish TFNPNP complexity; and (b)we present algorithms that improve the dependency on the number of actions in the exponent from linear to logarithmic. In particular, if the number of states is constant, our algorithms run in polynomial time. The second part of the thesis considers multi-player turn-based stochastic games with terminal payoffs, where the players are restricted to stationary strategies. We study the approximate constrained existence problem of Nash equilibria: given a game that has a Nash equilibrium in which the payoff of every player lies in a given interval, compute a strategy profile that is an ε-Nash equilibrium and that satisfies the same constraints up to an additive error ε. Our main results are as follows: (a) we present an FNPNP algorithm for the problem; and(b)we establish that its decision version is NP-hard, already with two players. For the upperbound,weshowthatifaconstrainedNashequilibriumexists,thenthereexists one in which the non-zero probabilities are at least an inverse of a double-exponential in the i input size, and that such a strategy profile can be represented, up to an additive error ε, with floating-point numbers of polynomial size. We complement the upper bound with a lower bound on this approach: we present a game with only five players in which every constrained Nash equilibrium requires double-exponentially small probabilities. The two parts share a common technical toolkit: bounds on solutions of systems of polynomial inequalities that arise from real algebraic geometry, the floating-point representation of doubly-exponentially small numbers, and guess-and-verify procedures that resolve single-player games with an NP oracle.}, author = {Asadi, Ali}, issn = {2791-4585}, pages = {83}, publisher = {Institute of Science and Technology Austria}, title = {{Approximation of values and equilibria in stochastic games: Complexity and algorithms}}, doi = {10.15479/AT-ISTA-23079}, year = {2026}, }