@article{22318, abstract = {Many intended uses of differential privacy involve a continual mechanism that is set up to run continuously over a long period of time, making more statistical releases as either queries come in or the dataset is updated. In this paper, we give the first general treatment of privacy against adaptive adversaries for mechanisms that support dataset updates and a variety of queries, all arbitrarily interleaved. It also models a very general notion of neighboring, that includes both event-level and user-level privacy. We prove several concurrent composition theorems for continual mechanisms, which ensure privacy even when an adversary can interleave its queries and dataset updates to the different composed mechanisms. Previous concurrent composition theorems for differential privacy were only for the case when the dataset is static, with no adaptive updates. We also give the first interactive and continual generalizations of the “parallel composition theorem” for noninteractive differential privacy. Specifically, we show that the analogue of the noninteractive parallel composition theorem holds if either there are no adaptive dataset updates or each of the composed mechanisms satisfies pure differential privacy, but it fails to hold for composing approximately differentially private mechanisms with dataset updates. Thus, we prove a tight new composition theorem for this case. In addition, we prove concurrent filter compositions theorems for the scenarios in which the privacy parameters are adaptively chosen. We extend these results to other measures of differential privacy, including Rényi DP and 𝑓 -DP. We then formalize a set of general conditions on a continual mechanism M that runs multiple continual submechanisms such that the privacy guarantees of M follow directly using the above concurrent composition theorems on the sub-mechanisms, without further privacy loss. This enables us to give a simpler and modular privacy analysis of a recent continual histogram mechanism of Henzinger, Sricharan, and Steiner. In the case of approximate DP, ours is the first proof that shows that its privacy holds against adaptive adversaries. We also provide a framework that simplifies the analysis of local differential privacy when the protocol includes multi-round server-user interactions. Using this result, we simplify the privacy analysis of the core decomposition protocol of Dhulipala, Henzinger, Li, Liu, Sricharan, and Zhu [5].}, author = {Henzinger, Monika H and Safavi Hemami, Roodabeh and Vadhan, Salil}, issn = {2836-6573}, journal = {Proceedings of the ACM on Management of Data}, keywords = {differential privacy, concurrent composition, continual release, continual observation, data streaming, continual mechanisms, concurrent parallel composition, concurrent filter composition}, number = {2}, pages = {1--26}, publisher = {Association for Computing Machinery}, title = {{Concurrent composition for differentially private continual mechanisms}}, doi = {10.1145/3801895}, volume = {4}, year = {2026}, } @inproceedings{22294, abstract = {Modern computer systems store vast amounts of personal data, enabling advances in AI and ML but risking user privacy and trust. For privacy reasons, it is sometimes desired for an ML model to forget part of the data it was trained on. In this paper, we introduce a novel unlearning approach based on Forgetting Neural Networks (FNNs), a neuroscience-inspired architecture that explicitly encodes forgetting through multiplicative decay factors. While FNNs had previously been studied as a theoretical construct, we provide the first concrete implementation and demonstrate their effectiveness for targeted unlearning. We propose several variants with per-neuron forgetting factors, including rank-based assignments guided by activation levels, and evaluate them on MNIST and Fashion-MNIST benchmarks. Our method systematically removes information associated with forget sets while preserving performance on retained data. Membership inference attacks confirm the effectiveness of FNN-based unlearning in erasing information about the training data from the neural network. These results establish FNNs as a promising foundation for efficient and interpretable unlearning. }, author = {Hatua, Amartya and Nguyen, Trung and Cano Cordoba, Filip and Sung, Andrew}, booktitle = {Proceedings of the 18th International Conference on Agents and Artificial Intelligence}, isbn = {9789897587962}, issn = {2184-433X}, keywords = {Machine Unlearning, Neuroscience-Inspired Machine Learning, Membership Inference Attacks}, location = {Marbella, Spain}, pages = {1536--1546}, publisher = {SciTePress}, title = {{Machine unlearning using forgetting neural networks}}, doi = {10.5220/0014326500004052}, volume = {2}, year = {2026}, } @article{22322, abstract = {We study the problem of continually releasing statistics of an evolving dataset under differential privacy. In the event-level setting, we show the first polynomial lower bounds on the additive error for insertions-only graph problems such as maximum matching, degree histogram and k-core number computation. These results represent an exponential improvement on the polylogarithmic lower bounds of Fichtenberger, Henzinger and Ost [ESA 2021] for the former two problems, and are the first lower bounds in the continual release setting for the latter problem. Our results run counter to the intuition that the difference between insertions-only vs fully dynamic updates causes the gap between polylogarithmic and polynomial additive error. Indeed, we show that for estimating the size of the maximum matching or k-core number of a vertex, allowing small multiplicative approximations is what brings the additive error down to polylogarithmic. We complement these results with improved upper bounds on the additive error when no multiplicative approximation is allowed. Beyond graphs, our techniques also show that polynomial additive error is unavoidable for the Simultaneous Norm Estimation problem in the insertions-only setting. When multiplicative approximations are allowed, we circumvent this lower bound by giving the first continual mechanism with polylogarithmic additive error under (1 + ζ) multiplicative approximations, for any ζ > 0, for estimating all monotone symmetric norms simultaneously. In the item-level setting, we show polynomial lower bounds on the product of the multiplicative and the additive error of continual mechanisms for a large range of graph problems. To the best of our knowledge, these are the first lower bounds shown for any differentially private mechanism under continual release with multiplicative error. To obtain these results, we prove a new lower bound on the product of multiplicative and additive error for the 1-Way-Marginals problem, and give reductions from 1-Way-Marginals to our desired graph problems. This generalizes the prior results of Hardt and Talwar [STOC 2010] and Bun, Ullman and Vadhan [STOC 2014, SIAM J. Comput. 2018], who gave lower bounds on the additive error for the special case of mechanisms with no multiplicative error.}, author = {Aryanfard, Bardiya and Henzinger, Monika H and Saulpic, David and Sricharan, A. R.}, issn = {2836-6573}, journal = {Proceedings of the ACM on Management of Data}, number = {2}, pages = {1--27}, publisher = {Association for Computing Machinery}, title = {{Improved lower bounds for privacy under continual release}}, doi = {10.1145/3801903}, volume = {4}, year = {2026}, } @article{22326, abstract = {In many developmental systems, cells differentiate into a tissue by reading out morphogen concentration fields, a process fundamentally limited by noise. How much can the precision of this process be improved by nonlocal information, e.g., via cell-cell communication? Using a Bayes-optimal framework, we show that positional inference depends crucially on morphogen spatial correlations and on the "structural prior" that encodes the geometry of the cellular lattice performing the readout, thereby determining what a cell can reliably assume about the position of its neighbors when interpreting nonlocal morphogen signals. We derive upper bounds on positional information gain due to nonlocal readout and identify signal processing algorithms that approximate optimal positional inference, as well as simple chemical reaction schemes which implement such algorithms. Our theory suggests that correlational information can be exploited to significantly enhance developmental precision.}, author = {Zhang, Chen Y and Mateu Hoyos, Pablo and Brückner, David and Tkačik, Gašper}, issn = { 1079-7114}, journal = {Physical Review Letters}, publisher = {American Physical Society}, title = {{Nonlocal decoding of positional and correlational information during development}}, doi = {10.1103/mbjk-v4ym}, volume = {137}, year = {2026}, } @article{22333, abstract = {RNA polymerase II (Pol II) must be assembled in the cytoplasm before it enters the nucleus, where it transcribes protein-coding genes. Although transcription by Pol II is intensively studied, how this central multi-subunit enzyme is made and the role of dedicated assembly factors remains unclear. Here, we report the integrative structural analysis of a native human Pol II from the cytoplasm captured near the end of biogenesis. The complex contains Gdown1 and three biogenesis factors – RPAP2 and the critical small GTPases GPN1 and GPN3. Cryo-EM analysis of the complex reveals how Gdown1 and RPAP2 associate with Pol II and prevent the premature association of transcription factors. Further biochemical and cryo-EM analysis reveals how RPAP2 tethers GPN1–GPN3 to the complex and how the assembly of the RPAP2–GPN1–GPN3 complex is controlled by GTP hydrolysis. The combined results uncover a network of interactions that chaperone cytoplasmic Pol II to prevent aberrant interactions, reveal a molecular switch regulating biogenesis factor association, and suggest a general mechanism for the action of GPN-loop GTPase family of enzymes.}, author = {Hlavata, Annamaria and Neuditschko, Benjamin and Schellhaas, Ulla and Plaschka, Clemens and Herzog, Franz and Bernecky, Carrie A}, issn = {2041-1723}, journal = {Nature Communications}, publisher = {Springer Nature}, title = {{Structure of cytoplasmic RNA polymerase II}}, doi = {10.1038/s41467-026-75416-8}, year = {2026}, } @phdthesis{22017, author = {Kleinhanns, Tobias}, isbn = {978-3-99078-081-7}, issn = {2663-337X}, pages = {59}, publisher = {Institute of Science and Technology Austria}, title = {{Unraveling the origin and evolution of defects to enable advanced thermoelectric performance}}, doi = {10.15479/AT-ISTA-22017}, year = {2026}, } @phdthesis{22334, abstract = {Characterizing protein dynamics at the atomic level is essential for our understanding of biological mechanisms. Whether it is to facilitate metabolite transport, catalyze reactions, transmit signals, or regulate metabolism – proteins are constantly in motion and sample multiple conformational states to fulfill their function. Nuclear magnetic resonance (NMR) spectroscopy is particularly well suited to elucidate the dynamics of biomolecules on their complex free-energy landscape. In particular, solid-state magic-angle spinning (MAS) NMR enables the study of large molecular assemblies, protein crystals, or insoluble proteins at atomic resolution without an inherent molecular size limitation. MAS NMR experiments to probe protein dynamics are extremely versatile and sensitive to motional timescales from picoseconds to seconds. Over the past decades, technological advances, developments in experimental design, and new isotope-labeling approaches have further expanded the possibilities of this technique and significantly improved the accuracy of the determined motional parameters. Functionally important sites of proteins often contain aromatic residues. Their side-chain motions have therefore long served as valuable indicators of mechanistically relevant dynamics in NMR studies. In this thesis, site-specifically labeled aromatic residues act as sensitive reporters for MAS NMR studies of protein dynamics. The first part addresses how different environments impact side-chain motion by probing ring flips of phenylalanines and tyrosines in crystalline proteins and amyloid fibrils. It provides important insights for the analysis of dynamics obtained in non-native protein environments and emphasizes the complex factors that determine the timescale of internal dynamics. In the second part, the focus shifts towards methodological questions regarding the investigation of protein dynamics by 19F MAS NMR. The fluorine nucleus exhibits promising characteristics for NMR studies but also presents significant challenges, which is why the full methodological potential of 19F MAS NMR has not been fully realized yet. This work demonstrates that paramagnetic doping can considerably reduce the measurement time and improve the sensitivity of fluorinated samples. Finally, 19F MAS NMR is evaluated as a tool for studying protein side-chain dynamics on the example of tryptophans. The results illustrate the challenges in analyzing such experiments and lay the foundation for further development of 19F MAS NMR relaxation studies. Taken together, this thesis highlights the potential of combining specific isotope labeling, MAS NMR, and complementary methods such as crystallography and computational simulations to elucidate internal protein dynamics. The further development of such integrative approaches will be crucial to improving our understanding of complex mechanisms and protein function. }, author = {Becker, Lea Marie}, isbn = {978-3-99078-084-8}, issn = {2663-337X}, pages = {205}, publisher = {Institute of Science and Technology Austria}, title = {{Exploring protein dynamics using specific labeling approaches for solid-state MAS NMR}}, doi = {10.15479/AT-ISTA-22334}, year = {2026}, } @article{22105, abstract = {Protein conformational energy landscapes are shaped not only by intramolecular interactions but also by their environment. In protein crystals and protein–protein complexes, intermolecular contacts alter this energy landscape, but the exact nature of this alteration is difficult to decipher. Understanding how the crystal lattice affects protein dynamics is crucial for crystallography-based studies of motion, yet its influence on collective motions remains unclear. Aromatic ring flips in the hydrophobic core represent sensitive probes of such dynamics. Here, we compare the kinetics of aromatic ring flips in the protein GB1 in crystals, in complex with its binding partner IgG, and in solution, combining advanced isotope labelling with quantitative NMR methods. We show that rings in the core flip nearly a thousand times less frequently in crystals than in solution. Enhanced-sampling molecular dynamics simulations, based on a crystal structure of a GB1 variant reported in this work, reproduce these elevated barriers and reveal how the crystal restrains motions.}, author = {Becker, Lea Marie and Fu, Haohao and Tatman, Benjamin and Dreydoppel, Matthias and Kapitonova, Anna and Balazs, Daniel and Weininger, Ulrich and Engilberge, Sylvain and Chipot, Christophe and Schanda, Paul}, issn = {17554349}, journal = {Nature Chemistry}, publisher = {Springer Nature}, title = {{Aromatic ring flips reveal reshaping of protein dynamics in crystals and complexes}}, doi = {10.1038/s41557-026-02155-0}, year = {2026}, } @article{21777, abstract = {The advantageous characteristics attributed to the 19F nucleus have made it a popular target for nuclear magnetic resonance (NMR) once again in recent years. Aside from solution NMR, an increasing number of studies have been conducted applying solid-state magic-angle spinning (MAS) NMR to fluorine-labelled samples. Here, the high chemical shift anisotropy and strong dipolar couplings can be utilised to get structural insights into proteins and measure long distances. Despite increasing popularity and promising benefits, the sensitivity of biomolecular 19F MAS NMR often suffers from slow longitudinal T1 relaxation and therefore long recycle delays. In this work, we expand paramagnetic doping, an approach commonly used to reduce proton T1 relaxation times, to 19F-labelled biological samples. We study the effect of Gd(DTPA) and Gd(DTPA-BMA) on 19F T1 and T2, and 13C T1 and T2 relaxation in a [5-19F13C]-tryptophan-labelled protein via 19F-detected MAS NMR experiments. The observed paramagnetic relaxation enhancement substantially reduces measurement times of 19F MAS NMR experiments without compromising resolution. Additionally, we report the chemical shift assignments of all four fluorotryptophan signals in the 12×39 kDa-large protein TET2 using a mutagenesis approach.}, author = {Becker, Lea Marie and Toscano, Giorgia and Kapitonova, Anna and Singh, Rajkumar and Guillerm, Undina and Lichtenecker, Roman J. and Schanda, Paul}, issn = {2699-0016}, journal = {Magnetic Resonance}, number = {1}, pages = {29--37}, publisher = {Copernicus Publications}, title = {{Accelerated 19F biomolecular magic-angle spinning NMR with paramagnetic dopants}}, doi = {10.5194/mr-7-29-2026}, volume = {7}, year = {2026}, } @unpublished{22359, abstract = {We prove a mesoscopic central limit theorem for linear eigenvalue statistics of correlated Hermitian random matrices. The class considered here includes Wigner and Wigner-type matrices, as well as models whose entry correlations decay polynomially in the distance between index pairs. The proof combines a multivariate cumulant expansion with multi-resolvent local laws and a detailed analysis of the resulting variance kernel on the operator-level.}, author = {Lee, Jaehun and Erdös, László}, keywords = {Central limit theorem, universality, matrix Dyson equation, multi-resolvent local law}, title = {{Mesoscopic eigenvalue statistics for correlated random matrices}}, doi = {10.48550/arXiv.2607.05848}, year = {2026}, } @article{22360, abstract = {In this paper, we consider the rectangular random matrix X =(xij ) ∈ RN×n whose entries are iid with tail P(|xij | > t) ∼ t−α for some α> 0. We consider the regime N(n)/n → a > 1 as n tends to infinity. Our main interest lies in the right singular vector corresponding to the smallest singular value, which we will refer to as the ``bottom singular vector'', denoted by 𝔲. In this paper, we prove the following phase transition regarding the localization length of 𝔲: when α< 2 the localization length is O(n/ log n); when α> 2 the localization length is of order n. Similar results hold for all right singular vectors around the smallest singular value. The variational definition of the bottom singular vector suggests that the mechanism for this localization-delocalization transition when α goes across 2 is intrinsically different from the one for the top singular vector when α goes across 4}, author = {Bao, Zhigang and Lee, Jaehun and Xu, Xiaocong}, issn = {1096-0783}, journal = {Journal of Functional Analysis}, number = {4}, publisher = {Elsevier}, title = {{Phase transition for the bottom singular vector of rectangular random matrices}}, doi = {10.1016/j.jfa.2025.111266}, volume = {290}, year = {2026}, } @article{22362, abstract = {We present a systematic study of the environments of 25 luminous quasars at z > 6.5 from the ASPIRE program. Using JWST/NIRCam wide-field slitless spectroscopy data, we identified 487 galaxies at 5.3 ≲ z ≲ 7.0 exhibiting [O III] emission. Among these, 122 [O III] emitters lie within |Δvlos| < 1000 km s −1 of the quasars, corresponding to a ∼9.4-fold enhancement relative to the average galaxy density at other redshifts. Furthermore, we identified 16 [C II]-emitting galaxies at the quasar redshifts from Atacama Large Millimeter/submillimeter Array (ALMA) mosaic observations. A cross-correlation function analysis between quasars and [O III]+[C II] emitters yields a cross-correlation length of r 8.68 h cMpc 0 QG 0.55 = +0.51 1 and an autocorrelation of r 15.76 h cMpc 0 QQ 2.70 = +2.48 1 , indicating that z ∼ 7 quasars reside in dark matter halos with Mhalo 1012.27 0.26 M 0.21 = + and have a quasar lifetime of tQ 10 yr 7.05 1.01 0.95 = + . Notably, the number of [O III]-emitting galaxies at quasar redshifts varies significantly from field to field, ranging from 0 to 20, highlighting a diverse quasar environment. Remarkably, seven quasars trace significant galaxy overdensities (i.e., protoclusters), with δgal > 5 within a volume of V ∼ 500 cMpc3 . We also find that |Δvlos| increases rapidly toward smaller galaxy–quasar separations in protocluster fields, consistent with galaxy kinematics around extremely massive halos in cosmological simulations. By combining JWST and ALMA data, we reveal the complex and diverse environments of these early quasars, providing robust evidence that the earliest luminous quasars are effective tracers of galaxy overdensities, albeit with substantial field-to-field variation.}, author = {Wang, Feige and Champagne, Jaclyn B. and Huang, Jiamu and Yang, Jinyi and Hennawi, Joseph F. and Fan, Xiaohui and Zhang, Haowen and Costa, Tiago and Decarli, Roberto and Habouzit, Melanie and Sun, Fengwu and Bañados, Eduardo and Jin, Xiangyu and Kakiichi, Koki and Meyer, Romain A. and Wu, Yunjing and Belladitta, Silvia and Blecha, Laura and Bosman, Sarah E.I. and Cai, Zheng and Connor, Thomas and Davies, Frederick B. and Eilers, Anna Christina and Haiman, Zoltán and Jun, Hyunsung D. and Li, Mingyu and Li, Zihao and Liu, Weizhe and Lupi, Alessandro and Lyu, Jianwei and Mazzucchelli, Chiara and Onoue, Masafusa and Pizzati, Elia and Pudoka, Maria and Rojas-Ruiz, Sofía and Schindler, Jan Torge and Shen, Yue and Tee, Wei Leong and Trakhtenbrot, Benny and Trebitsch, Maxime and Vestergaard, Marianne and Volonteri, Marta and Walter, Fabian and Zhang, Huanian and Zou, Siwei}, issn = {15384357}, journal = {Astrophysical Journal}, number = {1}, publisher = {IOP Publishing}, title = {{ASPIRE: The environments and dark matter halos of luminous quasars in the epoch of reionization}}, doi = {10.3847/1538-4357/ae7bfa}, volume = {1006}, year = {2026}, } @article{22364, abstract = {Finding the first generation of (Population III or Pop III) stars is one of the most ambitious and exciting challenges of astrophysics. JWST opened concrete prospects for their detection during the Epoch of Reionization, where increasing evidence suggests that residual Pop III formation may persist, even within pristine pockets of high-mass halos, due to inhomogeneous enrichment. However, the identification of Pop III stars within globally enriched environments will be challenging. We investigate the detectability of a subdominant Pop III component in/around massive (M⋆ ≳ 10^9 M⊙) galaxies at z ≈ 6.5–9 from the dustyGadget cosmological simulation suite, and the confusion arising from second-generation (Pop II) stars in their surroundings. We find that young (≲1 Myr), massive (MIII ∼ 6 × 10^5 M⊙) Pop III clusters forming within these galaxy environments are responsible for strong HeII1640 line emission (LHeII1640 ≳ 10^41 erg ^s−1), which would be detectable with ≈10(50) hr of medium-resolution observations with NIRSpec/IFU at z ≈ 6(10). These bright luminosities cannot be produced by standard Pop II populations alone. On the other hand, the dominant Pop II component within massive “hybrid” Pop III hosts powers strong metal line emission (L[OIII]5007 ≳ 10^42 erg s^−1), indicating that the detection of metal lines alone cannot exclude the presence of Pop IIIs in high-z galaxy environments. We further discuss candidate selection strategies based on Lyα, Hα, and Hβ emission, and how spatially resolved observations may enable the detection of isolated, pristine pockets in the outskirts of massive halos.}, author = {Venditti, Alessandra and Graziani, Luca and Schneider, Raffaella and Bromm, Volker and Muñoz, Julian B. and Di Cesare, Claudia and Valiante, Rosa and Calabrò, Antonello and Maiolino, Roberto and Finkelstein, Steven L. and Parente, Massimiliano and Saggini, Matteo and Chisholm, John}, issn = {1538-4357}, journal = {The Astrophysical Journal}, number = {2}, publisher = {IOP Publishing}, title = {{Catching the nebular needle in a polluted haystack: Line-emission signatures from population III-forming pockets around massive galaxies at the end of reionization}}, doi = {10.3847/1538-4357/ae7b2c}, volume = {1005}, year = {2026}, } @article{22369, abstract = {The high-redshift progenitors of present-day galaxy clusters are believed to substantially contribute to the global star formation rate density and drive the large-scale reionisation of the Universe. Here we present a blind and unbiased search for and characterisation of galaxy overdensities during the reionisation epoch at redshifts z ∼ 5.5 − 7 based on rest-frame optical JWST/NIRCam grism spectroscopy of the Abell 2744 lensing field as part of the JWST All the Little Things (ALT) survey. Using a physically motivated, cosmological inference friends-of-friends (FoF) algorithm, we identified six galaxy overdensities, including five robust systems at z = 5.66–6.77. They are all characterised by total halo masses of Mhalo ≳ 1011 M⊙, inferred from a range of proxies. We find that the galaxy members in these overdense environments are on average less massive though equally metal-rich, and generally comprised of younger stellar populations, as indicated by their bluer spectral slopes and less prominent Balmer breaks compared to field galaxies at similar redshifts. Further, we use this novel rest-frame optical selection of galaxy proto-clusters to infer the fraction and 3D distribution of strong Lyman-α emitters (LAEs) and damped Lyman-α absorbers (DLAs) in the overdensity environments. We find that two out of the six galaxy overdensities have excess H I absorption compared to the field average, while the other four are consistent within their large scatter in density. These results present the first direct observational constraints on the tomography of the dense, neutral gas reservoirs in large-scale galaxy overdensities at z > 5 and highlight the limitations of pre-JWST searches for reionisation-era galaxy overdensities relying on the detection of strong LAEs alone.}, author = {Terp, Chamilla and Heintz, Kasper E. and Matthee, Jorryt J and Naidu, Rohan P. and Oesch, Pascal A. and Witten, Callum and Kashino, Daichi and Pollock, Clara L. and Di Cesare, Claudia and Torralba Torregrosa, Alberto}, issn = {1432-0746}, journal = {Astronomy & Astrophysics}, publisher = {EDP Sciences}, title = {{All the massive galaxy overdensities during reionisation: JWST rest-frame optical selection reveals young, chemically evolved galaxies embedded in dense, neutral gas at z > 5}}, doi = {10.1051/0004-6361/202659436}, volume = {710}, year = {2026}, } @article{22363, abstract = {Eukaryotic gene regulation relies on stochastic yet controlled promoter switching, in which genes transition between transcriptionally active and inactive states. Despite the molecular complexity of this process, recent studies have revealed a surprising invariance of the “switching correlation time” (TC)—the characteristic decay time of the autocorrelation function of promoter activity fluctuations—across gene expression levels in multiple genes and organisms. A biophysically plausible explanation for this invariance has so far been lacking. Here, we show that this empirical constraint imposes stringent requirements on minimal yet realistic models of transcriptional regulation. Specifically, reproducing TC–invariance requires regulatory architectures with at least four internal states and nonequilibrium dynamics that break detailed balance. Using Bayesian inference on Drosophila gap gene expression data, we demonstrate that such models i) quantitatively reproduce the observed TC–invariance, ii) remain robust to parameter perturbations, and iii) maximize information transmission from transcription factor concentration to gene expression. Remarkably, the TC-invariant modulation strategy we identify as optimal closely parallels contemporary control-theoretic results on the modulation of stochastic switching systems. Taken together, our results suggest that eukaryotic transcriptional regulation operates in a nonequilibrium regime to balance precision, reaction-rate limitations, and energy dissipation, thereby achieving near-optimal information transmission under fundamental physical constraints.}, author = {Zoller, Benjamin and Benichou, Alexis and Gregor, Thomas and Tkačik, Gašper}, issn = {1091-6490}, journal = {Proceedings of the National Academy of Sciences of the United States of America}, number = {28}, publisher = {National Academy of Sciences}, title = {{Invariant nonequilibrium dynamics in gene regulation optimize information flow}}, doi = {10.1073/pnas.2524855123}, volume = {123}, year = {2026}, } @article{22365, abstract = {Phase plates can, in principle, overcome the poor image contrast in cryo–electron microscopy (cryo-EM) and the resulting limits on the structural reconstruction of small proteins. However, previous designs have been unstable and compromised the high-resolution signal and have thus been unable to surpass results achieved by standard cryo-EM. Here, we show that the laser phase plate (LPP), installed in a modern, custom Titan Krios microscope, enhances the resolution in single-particle reconstruction of small proteins by improving specimen-motion correction and recovery of information from the early frames, as well as particle visualization, three-dimensional classification, and alignment. These advances use standard defocus ranges and reconstruction procedures but open the door to LPP-tailored protocols, offering further improvements by leveraging the LPP demonstrated here.}, author = {Petrov, Petar N and Zhang, Jessie T. and Remis, Jonathan and Axelrod, Jeremy J. and Cheng, Hang and Cooper, Eric S. and Hicklin, Ian K. and Sandhaus, Shahar and Schnurr, Cooper and Glaeser, Robert M. and Müller, Holger}, issn = {1095-9203}, journal = {Science}, number = {6807}, pages = {195--196}, publisher = {AAAS}, title = {{Laser phase plate improves structure determination of small proteins by cryo-EM}}, doi = {10.1126/science.aeh0665}, volume = {393}, year = {2026}, } @article{22361, abstract = {Causal optimal transport and adapted Wasserstein distance have applications in different fields from optimization to mathematical finance and machine learning. The goal of this article is to provide equivalent formulations of these concepts in classic probabilistic language. In particular, we prove a Skorokhod representation theorem for adapted weak convergence, reformulate the equivalence of stochastic processes using Markovian lifts, and give an expression for the adapted Wasserstein distance based on representing processes on a common stochastic basis.}, author = {Beiglböck, Mathias and Pflügl, Susanne and Schrott, Stefan}, issn = {0304-4149}, journal = {Stochastic Processes and their Applications}, publisher = {Elsevier}, title = {{A probabilistic view on the adapted Wasserstein distance}}, doi = {10.1016/j.spa.2026.105032}, volume = {201}, year = {2026}, } @article{22372, abstract = {Neurons acquire polarity by specifying one neurite as the axon, whereas the others become dendrites. But how this fundamental asymmetry is established remains unclear1. Neuronal polarization has been thought to rely primarily on growth cones that sense external cues2. Here we show that growth cones alone do not direct this process and that the soma acts as a central organizer of neuronal polarization. Using live imaging and genetic loss-of-function approaches in vivo, combined with optogenetic control and local cytoskeletal perturbations in cultured neurons, we uncover a soma-initiated oscillatory program that primes axon selection. Periodic actin branching that depends on the actin-related protein 2/3 (ARP2/3) complex at the soma remodels a global actomyosin network, thereby generating an actin wave that retracts neurites before propagating into a single neurite tip. Exposure to this wave relaxes local actomyosin contractility, which drives a transient microtubule-based protrusion and biases this neurite towards axon fate. As the cell exits this oscillatory stage, this neurite can overcome global inhibition and extend independently of ARP2/3, whereas actomyosin activity suppresses axon formation in the remaining neurites so that they subsequently become dendrites. This soma-driven mechanism ensures the emergence of a single axon independent of environmental cues and underpins the unidirectional information flow in neuronal circuits.}, author = {Lin, Tien Chen and Coles, Charlotte H. and Alfadil, Eissa and Fäßler, Florian and Husch, Andreas and Dupraz, Sebastian and Pietralla, Thorben and Narita, Akihiro and Schelski, Max and Flynn, Kevin C. and Stern, Sina and Möhl, Christoph and Hilton, Brett J. and Vauti, Franz and Arnold, Hans Henning and Schur, Florian Km and Bradke, Frank}, issn = {1476-4687}, journal = {Nature}, publisher = {Springer Nature}, title = {{An intrinsic cytoskeletal oscillator establishes neuronal polarity}}, doi = {10.1038/s41586-026-10755-6}, year = {2026}, } @phdthesis{22255, abstract = {This thesis studies spectral rigidity and nonrigidity phenomena in dynamical systems. The central question is whether a dynamical system can be determined, up to a natural conjugacy, from its spectrum. We consider three related spectra: the length spectrum, the action spectrum, and the Lyapunov spectrum. The first part of the thesis concerns Liouville metrics on the two-dimensional torus. It is a long-standing folklore conjecture that Liouville metrics are the only integrable metrics on the torus. We prove a length-spectral rigidity result for linear conformal deformations of Liouville metrics by exploiting the dynamical properties of the rational tori -- analogues of the resonant convex caustics in billiards. We also establish a complementary classification result showing that marked-length-isospectral Liouville metrics are characterized by rearrangements of the one-dimensional functions appearing in their conformal factors, generalizing a theorem of Abbondandolo-Mazzucchelli. In particular, the second result gives nonrigidity examples within the class of Liouville metrics. The second part of the thesis studies the standard map from the viewpoint of action and Lyapunov spectra. We construct nontrivial deformations of the standard map which preserve the symplectic actions (respectively, the Lyapunov exponents) of infinitely many periodic orbits accumulating on an invariant curve. The proof combines a resonant normal form construction with Picard iteration schemes to obtain a sequence of periodic orbits accumulating on an invariant curve with a Liouville rotation number. Within the resonant normal forms we capture the dependence of these periodic orbits on the resonant Fourier coefficients of the dynamics on the invariant curve and, using the contraction mapping principle, obtain a suitable deformation achieving the prescribed spectral data associated with this sequence of orbits. The result can be viewed as a symplectic twist-map analogue of a length-spectral nonrigidity phenomenon for Riemannian manifolds and convex billiards, and it motivates the existence problem for similar 'partially length-isospectral' deformations of strictly convex billiard tables. }, author = {Li, Yunzhe}, issn = {2663-337X}, pages = {131}, publisher = {Institute of Science and Technology Austria}, title = {{Spectral rigidity and nonrigidity of dynamical systems}}, doi = {10.15479/AT-ISTA-22255}, year = {2026}, } @article{22371, abstract = {Amoeboid cell migration is key to efficient T cell immunity. Spatial polarization of organelles within cells, including endo-lysosomes, is a prerequisite of migration. However, how ultrastructural polarization is linked to the signaling requirements governing T cell migration remains unknown. Here we show that signaling molecules generated by endo-lysosome-localized kinases regulate velocity of amoeboid migration. Specifically, imaging of T cells identifies accumulation of endo-lysosomes decorated with the lipid kinases VPS34–PIKfyve at the uropod of polarized cells. Activity of VPS34 and PIKfyve regulates speed, but not directedness, of migrating T cells. Mechanistically, PI(3,5)P2 generated by the sequential action of VPS34 and PIKfyve, mediates Ca2+ efflux from lysosomes via the mucolipin TRP cation channel 1 (TRPML1), thus controlling activity of myosin IIA and hence the generation of propulsive force through retrograde actin flow. The VPS34–PIKfyve kinases also regulate velocity of myeloid cells, as well as of the amoeba Dictyostelium discoideum – establishing the axis as an evolutionarily conserved speed control system of amoeboid cell migration.}, author = {Dehio, Philippe G and Michard, Céline and Yam-Puc, Juan Carlos and Martí I Líndez, Adrià Arnau and Jandke, Anett and Unterstab, Gunhild and Fabre, Lucien and Sauteur, Loïc and Artinger, Marc and Legler, Daniel F. and Sixt, Michael K and Schaefer, Thorsten and Wymann, Matthias P. and Okkenhaug, Klaus and Soldati, Thierry and Mehling, Matthias and Hess, Christoph}, issn = {1469-3178}, journal = {EMBO Reports}, publisher = {Springer Nature}, title = {{A conserved VPS34-PIKfyve-TRPML1-myosin II axis regulates the speed of amoeboid cell migration}}, doi = {10.1038/s44319-026-00861-x}, year = {2026}, }