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Hao Chen

Publications and source records attributed to Hao Chen.

At least 19 recordsLinked to original sources

scTREAT: Latent Diffusion for Single-Cell Drug-Response Prediction

Generating drug-induced transcriptional responses requires a model to account for cellular background together with molecular identity and dose. We present scTREAT, the first diffusion framework to factorize state and drug guidance for single-cell drug-response prediction. A shared latent expression space connects baseline and response, while Guided Decomposable Attention (GD-Attn) injects a baseline representation and a dose-conditioned molecular embedding. Independent channel dropout exposes four conditioning states during training; inference combines three conditional predictions with separately specified state and drug coefficients, and dose modulates drug-guidance strength. On condition-level pseudobulk profiles derived from the Tahoe-100M single-cell atlas, scTREAT achieves the best value on 10 of 12 metrics for unseen cell line-drug combinations (UC) and 11 of 12 for unseen drugs (UD). Ablations examine condition injection, molecular representation, and guidance design. On UD, the relative gains over the second-best model reach 36.11% and 34.21% for DEG logFC-Spearman and logFC-Pearson. These results demonstrate the effectiveness of combining shared latent expression modeling with explicit state and drug conditioning for response prediction.

q-bio.QM↗

EvoWorld: Towards Out-of-Sight World Evolution in Generative Video Models

Generative video models are increasingly used as visual world simulators, yet their primary strength lies in rendering plausible pixels rather than reasoning about how a world should evolve. Coherent world evolution requires more than visual fidelity: when an event occurs, a model must infer its consequences for the entities in the world and then render the resulting state. For example, after a wild beast appears, the model should not only depict the wild beast, but also infer whether a nearby person should flee, take cover, or fight back based on the realized scene. Existing diffusion-based video models lack an explicit mechanism for maintaining world state and reasoning over such event-conditioned consequences, often producing visually plausible but behaviorally static or causally inconsistent outputs. To make this reasoning gap concrete and measurable, we propose a new problem, Out-of-Sight Causal Evolution, which requires a model to render an event, reason about its consequences for the evolving world state, and reveal a causally plausible outcome as the world continues to evolve, even out of sight. As a baseline reference solution, we introduce EvoWorld, a brain-renderer collaboration framework in which a vision-language model serves as the world brain: it observes generated segments, maintains an evolving account of the world, and reasons about plausible state transitions, while a segment-autoregressive video renderer realizes them visually. We further introduce EvoWorld-Data and EvoWorld-Bench for training and evaluating event realization, causal reactions, and revisit consistency. Experiments show that EvoWorld substantially improves event-conditioned causal evolution over recent models while preserving visual quality and consistency, establishing a reference point for reasoning-guided, autonomous world evolution beyond the current field of view.

cs.CV↗

META-Robot: Self-Cognition and Capability Scaling in Agentic Robots

LLM-based robotic agent systems can generate programs for robot control, yet their generalization to new tasks often depends on elaborate scaffolding. Expanding their skill repertoires alone offers limited guidance on how to assess new capabilities or identify what remains beyond their reach. We introduce META-Robot, a framework that couples self cognition with capability scaling by expanding the criteria through which an agent evaluates and develops its skills. At its core, action-level predicates make execution outcomes explicit and available for LLM reasoning. The agent uses these assessments to identify its own limitations, extend relevant evaluation criteria, and guide the structured expansion of its skills. Proprioceptive feedback further grounds this process in the robot's physical state, enriching the evidence available for self-cognition. Experiments in simulation and on real robots demonstrate stronger overall task performance, generalization to new tasks, continued expansion of skills and evaluation criteria, and effective use of non-visual proprioceptive signals.

cs.RO↗

CellCanon: An Agentic Cellular World Model for Prediction, Explanation, and Observation-Driven Updating

Biological discovery requires using molecular knowledge and new measurements to infer responses beyond the conditions already observed. We introduce CellCanon, the first agentic cellular world model to unify single-cell expression prediction, evidence-grounded explanation, and observation-driven updating. Its predictive core reuses condition-level biological evidence across gene-specific numerical readouts to guide single-cell expression generation. A shared world state links predictions, acquired measurements, and source-linked claims, supporting explanation and revision. On 339 held-out SciPlex3 conditions across three cell lines, CellCanon improves differential-expression AUPRC and Macro-F1 over the best baseline for each metric by 63.3% and 17.3%, respectively, and direction Macro-F1 by 7.2%. Relative to gene-wise reasoning on matched drug-cell cohorts, measured language-model token use falls by 99.77% for Predict and 98.41% for Explain. On the source-grounded benchmark, Explain correctly answers all answerable questions with supporting proofs and identifies all insufficient-evidence cases. In simulated experimental feedback, Update uses one measured source context per drug to exceed the best fine-tuned baselines in differential-expression AUPRC and Macro-F1 without changing model weights. Together, these capabilities support a cumulative account of cellular responses, with predictions and biological judgments that can be revised as evidence accumulates.

q-bio.QM↗

When Predictive Fit Misleads: Selecting Marketing Mix Models Using Experimental RoAS Benchmarks

Marketing Mix Models (MMMs) are used to estimate channel-level Return on Ad Spend (RoAS) and guide marketing investment, yet competing specifications are usually compared on predictive-fit metrics such as out-of-sample R-squared, MAPE, or RMSE. We show that predictive fit can diverge from recovery of the causal quantities that drive marketing decisions. In simulations with known RoAS, the best-fitting specification is often not the one that recovers RoAS most accurately; replicated studies show that this disagreement is systematic and persists under media-spend collinearity, noise, and a misspecified carryover shape. Selecting specifications against experimental RoAS benchmarks, even imprecise ones, improves RoAS recovery relative to fit-based selection, and a real-world application with experimental benchmarks shows the same pattern. We propose an applied workflow: calibrate MMM specifications against estimand-aligned experimental benchmarks when they exist, and otherwise report RoAS sensitivity across plausible specifications rather than relying on a single best-fitting model.

stat.AP↗

Agnostic and efficient detection of $\mathbb{Z}_2$ symmetry-protected topological phases in projected entangled-pair states

Symmetry-protected topological (SPT) phases are the simplest example of quantum phases that cannot be detected by local order parameters. Their classification is by now well-established from multiple perspectives, a prominent one being via tensor network states. The practical question, however, is not mere classification, but detection: given the ground state of an interacting Hamiltonian and a symmetry group $G$ along with its representation, is there an efficient way to tell if the state is in a SPT phase with respect to $G$? While there exist such practical tests in one spatial dimension (1D), methods in 2D have so far been restricted to finite-size systems or require an explicit form of virtual symmetries of the tensor networks representing the ground state. Here, we develop an agnostic and efficient method to detect interacting $\mathbb{Z}_2$ 2D SPT phases, using an infinite projected entangled-pair (PEPS) representation of the ground state. The method is agnostic to the symmetry representation in the virtual space of the PEPS tensor and applicable independent of the bond dimension of the tensors. Moreover, it is efficient as it does not require finite-size scalings: it works directly in the thermodynamic limit. We numerically demonstrate the procedure by mapping out phase boundaries away from fixed-point wavefunctions. We extract the SPT label cocycle data explicitly from the PEPS tensor.

cond-mat.str-el↗

TorchUMM: A Unified Multimodal Model Codebase for Evaluation, Analysis, and Post-training

Recent advances in unified multimodal models (UMMs) have led to a proliferation of architectures capable of understanding, generating, and editing across visual and textual modalities. However, developing a unified framework for UMMs remains challenging due to the diversity of model architectures and the heterogeneity of training paradigms and implementation details. In this paper, we present TorchUMM, the first unified codebase for comprehensive evaluation, analysis, and post-training across diverse UMM backbones, tasks, and datasets. TorchUMM supports a broad spectrum of models covering a wide range of scales and design paradigms. Our benchmark encompasses three core task dimensions: multimodal understanding, generation, and editing, and integrates both established and novel datasets to evaluate perception, reasoning, compositionality, and instruction-following abilities. By providing a unified interface and standardized evaluation protocols, TorchUMM enables fair and reproducible comparisons across heterogeneous models and fosters deeper insights into their strengths and limitations, facilitating the development of more capable unified multimodal systems. Code is available at: https://github.com/AIFrontierLab/TorchUMM.

cs.AI↗

Growth of structure in holographic dark energy models: a posterior predictive comparison

Structure formation has been used to test the viability of the IR cutoff in the Tsallis holographic dark energy (THDE) model, and the future event horizon was found to be a viable IR cutoff (Phys. Rev. D 113, 123531 (2026)). Motivated by this, we constrain the HDE, THDE, and BHDE models using the combined Pantheon+ SN Ia, OHD, DESI DR2, and CMB distance prior datasets, and propagate the MCMC posterior samples into the linear growth sector to obtain the predicted $fσ_8(z)$ and $S_8(z)$ histories under the smooth dark energy approximation. We find that the growth predictions of HDE and BHDE are nearly indistinguishable, while those of THDE lie lowest. A posterior predictive $χ^2$ comparison shows that current $fσ_8$ measurements are statistically consistent with all three models, whereas the $S_8$ comparison yields markedly larger $χ^2$ values for HDE and BHDE and a value for THDE close to that of $Λ$CDM. As an illustrative diagnostic, we construct the $(fσ_8, S_8)$ plane and find that the trajectories of THDE and $Λ$CDM reach the vicinity of the current data region, while those of HDE and BHDE do not. Our results indicate that structure growth observables provide a promising probe for discriminating among holographic dark energy models, while a definitive discrimination will require a joint background and growth likelihood and consistent growth measurements.

gr-qc↗

GlucoAgent: Personalized Glucose Forecasting from Multimodal Personal Context

Continuous glucose monitors, smartwatches, meal logs, and health profiles form a rich multimodal personal context that can significantly enhance glucose forecasting. However, existing methods struggle to effectively utilize these signals to improve glucose prediction because the relevance of different modalities varies drastically across individuals and time. We present GlucoAgent, an LLM-based agentic system that addresses this challenge through dynamic, case-by-case analysis at inference time. For each forecast, GlucoAgent writes and runs code over an individual's multimodal context and returns predictions with a reason and supporting evidence. The generated programs are highly diverse, ranging from retrieving similar past meals to fitting and back-testing physiological and statistical models. On CGMacros, a multimodal glucose dataset, GlucoAgent outperforms time series foundation models on every forecasting horizon, achieving an average RMSE of 22.5 mg/dL compared to 23.5 mg/dL of Chronos-2, the leading multimodal time series foundation model. Furthermore, GlucoAgent is highly effective at leveraging multimodal data. The addition of multimodal data reduces its average RMSE by 1.4 mg/dL (24.0 mg/dL to 22.5 mg/dL), compared to a marginal 0.3 mg/dL (23.8 mg/dL to 23.5 mg/dL) improvement for Chronos-2. This advantage is most pronounced in challenging post-meal windows, where GlucoAgent uses multimodal context to reduce 60-minute forecast RMSE by 4.6 mg/dL (31.0 mg/dL to 26.5 mg/dL), far exceeding the 0.8 mg/dL (31.9 mg/dL to 31.1 mg/dL) reduction achieved by Chronos-2.

cs.AI↗

PyRUA-DataFarm: LLM Agent as a Cost-Efficient Teleoperator for Real-Ready Robot Data

Teleoperation remains the default way to collect robot demonstrations, but every episode costs robot and operator time, and every new task starts from scratch. We ask whether a coding agent can take over the teleoperator's job. In our DataFarm, the agent receives a data request and one calibration episode of the robot in the target scene and rebuilds the task in simulation: it writes the scene, an expert controller, and a success judge. The simulator supplies exact actions, and a video model conditioned on real images renders each rollout as photographic video, generating all camera views together consistently. The output is real-ready data: synchronized camera views labelled with the robot's actions, on which a policy can be trained directly and deployed on the real robot. Independent judges certify the expert and every rendered episode before admission. On five real-robot tasks, policies trained only on farm data match policies trained on as many teleoperated episodes (93 vs. 84 successes in 100 trials), and under an unseen tablecloth and coloured light they keep 87 successes where the teleoperation-trained policies fall to 46. Adapting a task is fully automatic and costs \$21 of API usage on average, paid once per task, plus \$5 for a render contract; every further episode costs \$0.80 on average for simulation, rendering, and review, with no robot or operator. One hour of three-view data for a task costs \$107 on average, these costs included, slightly below a quote of \$117 for teleoperation in China and below \$290 in labour alone in North America.

cs.RO↗

Meson spectra in a screened relativized quark model

In this work, we employed the modified Godfrey--Isgur model to systematically investigate the mass spectra of several light, heavy-light, and heavy-heavy meson systems. In this model, a screened potential is employed to phenomenologically account for modifications to the long-range confining interaction associated with unquenched effects. We performed a global refit of the relevant model parameters to a combined set of 90 adopted meson masses spanning all three sectors, ensuring a consistent parameter determination across the different meson systems. Using the resulting parameter set, we calculated the low-lying and highly excited spectra and the corresponding mixed states in different meson families, and compared our results with existing experimental data and other theoretical results. The assignment of several newly observed structures (such as $B_c^*$ and $D_{s1}(2933)$) have also been discussed based on their predicted masses. Overall, the model describes several main spectroscopic features across different flavors and provides mass predictions for highly excited states that have not yet been experimentally established.

hep-ph↗

Learning to Adjudicate: Verifier-Guided Multi-Agent Reasoning for E-Commerce Relevance

Relevance modeling is fundamental to e-commerce search, determining how well retrieved products satisfy the needs expressed in a user's query. Accurate judgments require interpreting user intent, comparing product attributes, and applying business-specific matching criteria. Current methods based on large language models (LLMs) leverage contextual understanding and reasoning, focusing on incorporating domain-specific context and enhancing reasoning performance. Despite these advances, difficult query-product pairs remain challenging when evidence from different perspectives supports conflicting conclusions. A single reasoning pass may fail to reconcile these conflicts and ensure that decisive evidence guides the final judgment. To address this challenge, we propose Collaborative Adjudication with Debate and Replay Experience (CADRE), a framework for evidence-based adjudication in e-commerce relevance assessment. CADRE organizes three expert agents sharing a frozen backbone to analyze product attributes, user intent, and business rules in separate contexts, while a trainable Verifier assesses their supporting evidence against the applicable matching criteria to determine relevance. Under expert disagreement, a Verifier-guided debate elicits targeted clarification and revision of disputed interpretations before final adjudication. We optimize the Verifier through multi-turn group relative policy optimization and adapt successful-experience replay so that trajectories yielding correct terminal labels can be reused alongside fresh rollouts in subsequent updates. For efficient online serving, we use CADRE as an offline teacher to distill its relevance judgments into a lightweight student model. Offline evaluations and online A/B tests on an e-commerce search advertising platform demonstrate that CADRE improves relevance classification and key business and relevance satisfaction metrics.

cs.IR↗

Molecular Curvature Enables Tubular π-Stacked Pathways in Three-Dimensional Conductive Metal-Organic Frameworks

Conductive metal-organic frameworks (MOFs) are commonly constructed from planar aromatic ligands, whose geometries favor conventional π-stacking arrangements. However, intrinsically twisted ligands offer an alternative geometric approach to directing aromatic packing and constructing unconventional framework architectures. Here, we employ intrinsically twisted, butterfly-shaped dibenzo[g,p]chrysene-2,3,6,7,10,11,14,15-octaol (DBC) ligands to construct a series of lanthanide MOFs. Single-crystal X-ray diffraction reveals an interpenetrated three-dimensional framework in which π-π interactions between the aromatic fragments generate axially extended tubular π-stacked pathways, alongside one-dimensional channels rich in hydrogen-bonding sites. Lanthanide substitution preserves the overall tubular framework topology while modulating aromatic stacking distances and local pore environments. PrDBC single crystals exhibit mixed electron-proton transport, with electron and proton conductivities reaching 1.62 x 10-3 and 4.37 x 10-4 S cm-1, respectively, at 338 K and 30% relative humidity. This work highlights molecular curvature as a structural design strategy for constructing three-dimensional conductive MOFs that integrate tubular aromatic stacks with tunable pore environments for mixed electron-proton transport.

cond-mat.mtrl-sci↗

4K Image Super-Resolution on Mobile NPUs: Mobile AI 2026 Challenge Report

Image super-resolution is widely used on mobile devices for upscaling various types of image data. This creates a need for efficient deep learning-based models that are not only performant but can also be deployed on neural processing units (NPUs) present in the majority of mobile and IoT chipsets. In this Mobile AI challenge, we address this problem and propose the participants to design fast solutions that can upsample images from Full HD to 4K resolution while running on popular mobile NPUs from Qualcomm and MediaTek. For this, the participants were provided with the DIV2K dataset and trained models to do an efficient 3X image upscaling. The competition had two tracks: in the first track, the models had to be fully quantized (INT8), and the runtime of all models was evaluated on the Qualcomm Snapdragon 8 Elite Gen 5 NPU. In the second track, the participants were developing floating-point solutions that were evaluated on the MediaTek Dimensity 9500 NPU. Top solutions proposed in this challenge are able to reconstruct 4K images under 5 milliseconds while reaching a PSNR score of 30 dB. A comprehensive description of the models developed in the challenge is provided in this paper.

cs.CV↗

Local Fan-type obstructions and Ore-type conditions for rainbow Hamiltonicity in graph systems

Let $G=(G_1,...,G_n)$ be a graph system on a common $n$-vertex set $V$. For $v\in V$, set \[ δ(v)=\min_{i\in[n]}d_{G_i}(v), \qquad E_{\cap}=\bigcap_{i=1}^n E(G_i), \] and let $d^c(u,v)$ denote the length of a shortest rainbow $u$--$v$ path. We study Hamiltonicity conditions imposed only on pairs at small rainbow distance. Suppose that every $G_i$ is $2$-connected and that \[ δ(u),δ(v)<\frac n2, \qquad d^c(u,v)\le2 \quad\Longrightarrow\quad uv\in E_{\cap}. \] Our main result shows that any system satisfying this local Fan-type condition but containing no rainbow Hamilton cycle must satisfy \[ E_{\cap}=\varnothing, \qquad \sum_{v\in V}δ(v)\le\frac{n^2-1}{2}. \] Consequently, either $E_{\cap}\ne\varnothing$ or $\sum_{v\in V}δ(v)\ge\lceil n^2/2\rceil$ guarantees a rainbow Hamilton cycle. We further prove that the local Ore-type condition \[ δ(u)+δ(v)<n, \qquad d^c(u,v)\le2 \quad\Longrightarrow\quad uv\in E_{\cap} \] already forces a rainbow Hamilton cycle. Along the way, the Fan-type hypothesis yields a rainbow Hamilton path and a rainbow $(n-1)$-cycle. For diagonal systems, our conditions reduce to the classical Fan and local Ore conditions. The proofs combine rainbow rotation--extension with a double-counting argument in an auxiliary digraph. Keywords: graph system; rainbow Hamilton cycle; rainbow distance; Fan-type condition; Ore-type condition; rotation--extension.

math.CO↗

Dimension Changes the Scale-Signal Channel in Nearest-Neighbor Two-Sample Testing

Nearest-neighbor two-sample tests are often analyzed with dimension fixed. We study the power of the generalized edge-count test on a directed 1-nearest-neighbor graph. This statistic combines a weighted sum and a difference of the two within-sample edge counts. For balanced isotropic Gaussian samples with $d/\log N\toγ>0$, we derive the connection probabilities under local location and scale alternatives. Under location alternatives, the two counts have equal mean shifts, which cancel in their difference. Under scale alternatives, the two counts instead have mean shifts of opposite signs. We also derive the growth rate of the null expectation $\mathbb{E}_0C_3$, where $C_3$ counts pairs of directed edges sharing exactly one vertex. On an explicit range of $γ$, we establish local-power limits strictly above the test level for scale alternatives in the difference component at the scale $|\varepsilon_N|\asymp (\mathbb{E}_0C_3)^{1/2}/(Nd)$. Here $\mathbb{E}_0C_3$ gives the variance order of the difference count under these local alternatives. At this scale, the standardized drift of the weighted sum vanishes. When $d=1$, the weighted component instead detects local Gaussian scale alternatives while the difference component has no limiting drift. Thus dimension changes both the magnitude of a detectable scale difference and the component of the test that detects it.

math.ST↗

FuzzAgent: Multi-Agent System for End-to-End Evolutionary Library Fuzzing

Library fuzzing synthesizes harnesses that expose new API interactions, but deploying it end to end still requires extensive project-specific integration. Existing LLM-based systems automate individual steps, yet they treat execution outcomes as coarse signals: a stalled campaign does not reveal which state blocks progress, and a crash trace does not reveal whether the library or the harness is at fault. We present FuzzAgent, a multi-agent system that builds and evolves a complete fuzzing campaign from a source tree alone. Specialized agents acquire project knowledge and repair campaign artifacts automatically. Hierarchical coverage diagnosis localizes blockers from modules down to branches, and dependency-aware generation converts them into harnesses with the required API lifecycle. Crash validation recovers runtime object states to distinguish harness misuse from library bugs. We evaluate FuzzAgent on 20 real-world C/C++ libraries against five state-of-the-art baselines (OSS-Fuzz, OSS-Fuzz-Gen, PromptFuzz, PromeFuzz, and ProteusFuzz). FuzzAgent completes the full fuzzing lifecycle for all 20 libraries without human intervention at $3.17 per library. On the 20 libraries, it reaches 179619 branches, exceeding OSS-Fuzz, PromptFuzz, ProteusFuzz, PromeFuzz, and OSS-Fuzz-Gen by 45.1%, 73.2%, 87.7%, 92.1%, and 191.2%, respectively. FuzzAgent also identifies 102 new library bugs, 90 of which have already been acknowledged or fixed by upstream maintainers.

cs.SE↗

Approximation of the relaxed Euler system at the level of the compressible Navier-Stokes equations

We study the global well-posedness of the Cauchy problem in $\mathbb R^d$, $d\geq2$, for the relaxed compressible Euler system with a Maxwell-type constitutive law for the stress tensor. We show that the corresponding compressible Navier-Stokes solutions serve as both relaxation limits and large-time asymptotic profiles of the global relaxed Euler solutions constructed here. Given a Navier-Stokes background satisfying suitable boundedness and decay assumptions, we construct global smooth relaxed Euler solutions for each fixed $α\in(0,1]$ and sufficiently small $\varepsilon>0$. Here, the background need not be small. After subtracting the stress initial layer, the approximation error is $O(\varepsilon^α)$ uniformly in time. Under suitable additional conditions on the initial perturbations, this error decays in $L^2$ faster than the decay of standard Navier-Stokes background, uniformly in $\varepsilon$, identifying the background solution as a large-time asymptotic profile. As an application, we obtain the corresponding small-data results using classical Navier-Stokes theory to verify the background assumptions.

math.AP↗