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    "headline": "The River Model Kept Environmental DNA Nonnegative",
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    "dek": "A delayed stochastic source linked migratory fish movement to downstream DNA concentration.",
    "summary": "A delayed stochastic source linked migratory fish movement to downstream DNA concentration.",
    "body_text": "A preprint proposes a stochastic partial differential equation for river eDNA, with a delayed source driven by modeled fish migration. The authors derive analytical properties, design a discretization that remains nonnegative and apply it to midstream measurements with sensitivity analysis. It is an early mathematical framework, not a validated abundance estimator for all rivers or species.",
    "why_it_matters": "A delayed stochastic source linked migratory fish movement to downstream DNA concentration.",
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      "It is an early mathematical framework, not a validated abundance estimator for all rivers or species."
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    "tags": [
      "environmental DNA",
      "rivers",
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      "title": "arXiv preprint 2608.03364",
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