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Learning to sign changed my life after a brain injury

BBC News

As Tina walks onto the stage in front of hundreds of people she is beaming. She's collecting her British Sign Language (BSL) certificate which is the culmination of a journey that began with tragedy. Learning BSL has helped me say words that I cannot speak, she says. In 2018, while returning from a holiday, Tina fell down a flight of stairs and was in a coma for six weeks. The accident caused a traumatic brain injury that dramatically changed her life, leaving her struggling to speak.


Towards Unsupervised Training of Matching-based Graph Edit Distance Solver via Preference-aware GAN

arXiv.org Artificial Intelligence

Graph Edit Distance (GED) is a fundamental graph similarity metric widely used in various applications. However, computing GED is an NP-hard problem. Recent state-of-the-art hybrid GED solver has shown promising performance by formulating GED as a bipartite graph matching problem, then leveraging a generative diffusion model to predict node matching between two graphs, from which both the GED and its corresponding edit path can be extracted using a traditional algorithm. However, such methods typically rely heavily on ground-truth supervision, where the ground-truth node matchings are often costly to obtain in real-world scenarios. In this paper, we propose GEDRanker, a novel unsupervised GAN-based framework for GED computation. Specifically, GEDRanker consists of a matching-based GED solver and introduces an interpretable preference-aware discriminator. By leveraging preference signals over different node matchings derived from edit path lengths, the discriminator can guide the matching-based solver toward generating high-quality node matching without the need for ground-truth supervision. Extensive experiments on benchmark datasets demonstrate that our GEDRanker enables the matching-based GED solver to achieve near-optimal solution quality without any ground-truth supervision.


AbBiBench: A Benchmark for Antibody Binding Affinity Maturation and Design

arXiv.org Artificial Intelligence

We introduce AbBiBench (Antibody Binding Benchmarking), a benchmarking framework for antibody binding affinity maturation and design. Unlike previous strategies that evaluate antibodies in isolation, typically by comparing them to natural sequences with metrics such as amino acid recovery rate or structural RMSD, AbBiBench instead treats the antibody-antigen (Ab-Ag) complex as the fundamental unit. It evaluates an antibody design's binding potential by measuring how well a protein model scores the full Ab-Ag complex. We first curate, standardize, and share more than 184,500 experimental measurements of antibody mutants across 14 antibodies and 9 antigens-including influenza, lysozyme, HER2, VEGF, integrin, Ang2, and SARS-CoV-2-covering both heavy-chain and light-chain mutations. Using these datasets, we systematically compare 15 protein models including masked language models, autoregressive language models, inverse folding models, diffusion-based generative models, and geometric graph models by comparing the correlation between model likelihood and experimental affinity values. Additionally, to demonstrate AbBiBench's generative utility, we apply it to antibody F045-092 in order to introduce binding to influenza H1N1. We sample new antibody variants with the top-performing models, rank them by the structural integrity and biophysical properties of the Ab-Ag complex, and assess them with in vitro ELISA binding assays. Our findings show that structure-conditioned inverse folding models outperform others in both affinity correlation and generation tasks. Overall, AbBiBench provides a unified, biologically grounded evaluation framework to facilitate the development of more effective, function-aware antibody design models.


How Reinforcement Learning After Next-Token Prediction Facilitates Learning

arXiv.org Machine Learning

Recent advances in reasoning domains with neural networks have primarily been enabled by a training recipe that optimizes Large Language Models, previously trained to predict the next-token in a sequence, with reinforcement learning algorithms. We introduce a framework to study the success of this paradigm, and we theoretically expose the optimization mechanisms by which reinforcement learning improves over next-token prediction in this setting. We study learning from mixture distributions of short and long ``chain-of-thought'' sequences encoding a single task. In particular, when the task consists of predicting the parity of $d$ bits and long sequences are rare, we show how reinforcement learning after next-token prediction enables autoregressive transformers to generalize, whereas mere next-token prediction requires extreme statistical or computational resources to do so. We further explain how reinforcement learning leverages increased test-time computation, manifested in longer responses, to facilitate this learning process. In a simplified setting, we theoretically prove that autoregressive linear models following this training recipe can efficiently learn to predict the parity of $d$ bits as long as the proportion of long demonstrations in the data mix is not exponentially small in the input dimension $d$. Finally, we demonstrate these same phenomena in other settings, including the post-training of Llama-series models on mixture variations of common mathematical reasoning benchmarks.


Analyzing Data Quality and Decay in Mega-Constellations: A Physics-Informed Machine Learning Approach

arXiv.org Artificial Intelligence

In the era of mega-constellations, the need for accurate and publicly available information has become fundamental for satellite operators to guarantee the safety of spacecrafts and the Low Earth Orbit (LEO) space environment. This study critically evaluates the accuracy and reliability of publicly available ephemeris data for a LEO mega-constellation - Starlink. The goal of this work is twofold: (i) compare and analyze the quality of the data against high-precision numerical propagation. By analyzing two months of real orbital data for approximately 1500 Starlink satellites, we identify discrepancies between high precision numerical algorithms and the published ephemerides, recognizing the use of simplified dynamics at fixed thresholds, planned maneuvers, and limitations in uncertainty propagations. Furthermore, we compare data obtained from multiple sources to track and analyze deorbiting satellites over the same period. Empirically, we extract the acceleration profile of satellites during deorbiting and provide insights relating to the effects of non-conservative forces during reentry. For non-deorbiting satellites, the position Root Mean Square Error (RMSE) was approximately 300 m, while for deorbiting satellites it increased to about 600 m. Through this in-depth analysis, we highlight potential limitations in publicly available data for accurate and robust Space Situational Awareness (SSA), and importantly, we propose a data-driven model of satellite decay in mega-constellations. Keywords: Starlink, Low Earth Orbit, Physics-Informed Machine Learning, Space Situational Awareness, Satellite Decay 1. Introduction As the number of active satellites in Low Earth Orbit (LEO) continues to grow, ensuring their safe operation has become a complex challenge. Accurate trajectory prediction and collision avoidance are now essential, as overcrowding in LEO has significantly raised the likelihood of orbital collisions [1]. Such events not only threaten the functionality of space assets but also contribute to the accumulation of debris, increasing the risk of chain reaction scenarios like the Kessler syndrome [2].


Large Language Models for Imbalanced Classification: Diversity makes the difference

arXiv.org Machine Learning

Oversampling is one of the most widely used approaches for addressing imbalanced classification. The core idea is to generate additional minority samples to rebalance the dataset. Most existing methods, such as SMOTE, require converting categorical variables into numerical vectors, which often leads to information loss. Recently, large language model (LLM)-based methods have been introduced to overcome this limitation. However, current LLM-based approaches typically generate minority samples with limited diversity, reducing robustness and generalizability in downstream classification tasks. To address this gap, we propose a novel LLM-based oversampling method designed to enhance diversity. First, we introduce a sampling strategy that conditions synthetic sample generation on both minority labels and features. Second, we develop a new permutation strategy for fine-tuning pre-trained LLMs. Third, we fine-tune the LLM not only on minority samples but also on interpolated samples to further enrich variability. Extensive experiments on 10 tabular datasets demonstrate that our method significantly outperforms eight SOTA baselines. The generated synthetic samples are both realistic and diverse. Moreover, we provide theoretical analysis through an entropy-based perspective, proving that our method encourages diversity in the generated samples.


The Best PC Monitor for Most People Is 75 Off

WIRED

Dell's excellent 4K monitor is a perfect second screen for working from home. All products featured on WIRED are independently selected by our editors. However, we may receive compensation from retailers and/or from purchases of products through these links. If you're tired of staring a tiny laptop screen while working from home, consider scooping up our favorite desktop monitor for almost 25 percent off its normal price. The Dell 27 Plus 4K (8/10, WIRED Reivew) is currently marked down to just $228 on Amazon, the lowest we've seen yet for this smart and practical 4K screen.


Equity threatens mass direct action over use of actors' images in AI content

The Guardian

Equity confirmed it was supporting a Scottish actor who believes her image was used in the creation of Tilly Norwood (above), an AI-generated'actor'. Equity confirmed it was supporting a Scottish actor who believes her image was used in the creation of Tilly Norwood (above), an AI-generated'actor'. Equity threatens mass direct action over use of actors' images in AI content The performing arts union Equity has threatened mass direct action over tech and entertainment companies' use of its members' likenesses, images and voices in AI content without permission. Its general secretary, Paul W Fleming, said it planned to coordinate data requests en masse to companies to force them to disclose whether they used members' data in AI-generated material without consent. Last week the union confirmed its was supporting a Scottish actor who believes her image was used in the creation of the "AI actor" Tilly Norwood, which has been widely condemned by the film industry.


AI could make it harder to establish blame for medical failings, experts say

The Guardian

Where an AI system is used, patients could face difficulties showing fault in the event of a negative outcome, experts say. Where an AI system is used, patients could face difficulties showing fault in the event of a negative outcome, experts say. The use of artificial intelligence in healthcare could create a legally complex blame game when it comes to establishing liability for medical failings, experts have warned. The development of AI for clinical use has boomed, with researchers creating a host of tools, from algorithms to help interpret scans to systems that can aid with diagnoses . AI is also being developed to help manage hospitals, from optimising bed capacity to tackling supply chains.


The Download: planet hunting, and India's e-scooters

MIT Technology Review

Plus: The Trump administration has laid off thousands of federal health workers. The pendant on Rebecca Jensen-Clem's necklace is composed of 36 silver hexagons entwined in a honeycomb mosaic. At the Keck Observatory, in Hawaii, just as many segments make up a mirror that spans 33 feet, reflecting images of uncharted worlds for her to study. Jensen-Clem, an astronomer at the University of California, Santa Cruz, works with the Keck Observatory to try to detect new planets without leaving our own. It's a pursuit that faces a vast array of obstacles, for example wind, and fluctuations in atmospheric density and temperature. At her lab among the redwoods, Jensen-Clem and her students experiment with new technologies and software to help overcome the challenges, and see into space more clearly.