arXiv:2603.26858v1 Announce Type: cross Abstract: Single-cell RNA-seq data analysis typically requires representations that capture heterogeneous local structure across multiple scales while remaining stable and interpretable. In this work, we propose a hierarchical sheaf spectral embedding (HSSE) framework that constructs informative cell-level features based on persistent sheaf Laplacian analysis. Starting from scale-dependent low-dimensional embeddings, we define cell-centered local neighborhoods at multiple resolutions. For each local neighborhood, we construct a data-driven cellular sheaf that encodes local relationships among cells. We […]

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arXiv:2602.17826v1 Announce Type: new Abstract: Language models exhibit fundamental limitations — hallucination, brittleness, and lack of formal grounding — that are particularly problematic in high-stakes specialist fields requiring verifiable reasoning. I investigate whether formal domain ontologies can enhance language model reliability through retrieval-augmented generation. Using mathematics as proof of concept, I implement a neuro-symbolic pipeline leveraging the OpenMath ontology with hybrid retrieval and cross-encoder reranking to inject relevant definitions into model prompts. Evaluation on the MATH benchmark with […]

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arXiv:2603.24806v1 Announce Type: new Abstract: Diffusion models are increasingly used for robot learning, but current designs face a clear trade-off. Action-chunking diffusion policies like ManiCM are fast to run, yet they only predict short segments of motion. This makes them reactive, but unable to capture time-dependent motion primitives, such as following a spring-damper-like behavior with built-in dynamic profiles of acceleration and deceleration. Recently, Movement Primitive Diffusion (MPD) partially addresses this limitation by parameterizing full trajectories using Probabilistic Dynamic […]

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arXiv:2604.15341v1 Announce Type: new Abstract: Mixed Reality (MR) offers immersive and multimodal opportunities for education but remains difficult for teachers to author without technical expertise. We propose MRGEN, a conceptual framework for LLM-powered authoring tools to support teachers in creating MR learning activities that work on mobile devices (tablets and smartphones). MRGEN articulates three axes: Learning Objectives, MR Modality, and GAI Assistance. To validate our framework, we implemented a prototype based on the open-source MIXAP authoring platform and […]

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arXiv:2602.10251v1 Announce Type: new Abstract: AI chatbots are widely used by children and teens today, but they pose significant risks to youth’s privacy and safety due to both increasingly personal conversations and potential exposure to unsafe content. While children under 13 are protected by the Children’s Online Privacy Protection Act (COPPA), chatbot providers’ own privacy policies may also provide protections, since they typically prohibit children from accessing their platforms. Age gating is often employed to restrict children online, […]

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arXiv:2603.02229v1 Announce Type: new Abstract: Safety post-training has been studied extensively in single-step “chat” settings where safety typically refers to refusing harmful requests. We study an “agentic” (i.e., multi-step, tool-use) setting where safety refers to harmful actions directly taken by the LLM. We compare the effects of running direct preference optimization (DPO) on safety or helpfulness alone vs both metrics sequentially. As expected, training on one metric alone results in an extreme point along this frontier. However, unlike […]

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arXiv:2603.00611v1 Announce Type: new Abstract: Recently, Spectral Compressive Imaging (SCI) has achieved remarkable success, unlocking significant potential for dynamic spectral vision. However, existing reconstruction methods, primarily image-based, suffer from two limitations: (i) Encoding process masks spatial-spectral features, leading to uncertainty in reconstructing missing information from single compressed measurements, and (ii) The frame-by-frame reconstruction paradigm fails to ensure temporal consistency, which is crucial in the video perception. To address these challenges, this paper seeks to advance spectral reconstruction from […]

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Before the acceleration of AI, insider risk always centered on human intent. Security teams monitored high-risk employees who were prone to downloading files before leaving the company, or negligent employees who engaged in thoughtless behavior (e.g., clicking a phishing link.) In other words, the insider risk threat model was based on people doing things they shouldn’t. AI has fundamentally changed this paradigm. The risk is no longer limited to ill-intentioned employees but also to those who wish to […]

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