{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T01:36:10Z","timestamp":1760060170186,"version":"build-2065373602"},"reference-count":46,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2025,8,6]],"date-time":"2025-08-06T00:00:00Z","timestamp":1754438400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Research Impact Fund at Durham University"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Information"],"abstract":"<jats:p>Accurately estimating the radiation dose received by an individual is essential for evaluating potential damage caused by exposure to ionizing radiation. Most retrospective dosimetry methods require the time since exposure to be known and rely on calibration curves specific to that time point. In this work, we introduce a novel method tailored to the \u03b3-H2AX assay, which is a protein-based biomarker for radiation exposure, that enables the estimation of both the radiation dose and the time of exposure within a plausible post-exposure interval. Specifically, we extend calibration curves available at two distinct time points by incorporating the biological decay of foci, resulting in a model that captures the joint dependence of foci count on both dose and time. We demonstrate the applicability of this approach using both real-world and simulated data.<\/jats:p>","DOI":"10.3390\/info16080672","type":"journal-article","created":{"date-parts":[[2025,8,6]],"date-time":"2025-08-06T10:13:51Z","timestamp":1754475231000},"page":"672","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["A Procedure to Estimate Dose and Time of Exposure to Ionizing Radiation from the \u03b3-H2AX Assay"],"prefix":"10.3390","volume":"16","author":[{"given":"Yilun","family":"Cai","sequence":"first","affiliation":[{"name":"Department of Mathematical Sciences, Durham University, Durham DH1 3LE, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1849-7353","authenticated-orcid":false,"given":"Yingjuan","family":"Zhang","sequence":"additional","affiliation":[{"name":"Department of Mathematical Sciences, Durham University, Durham DH1 3LE, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0009-0008-3238-9133","authenticated-orcid":false,"given":"Hannah","family":"Mancey","sequence":"additional","affiliation":[{"name":"Cytogenetics Group of the Radiation, Chemical, Climate and Environmental Hazards Division, UK Health Security Agency, Chilton, Oxfordshire OX11 0RQ, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1041-8908","authenticated-orcid":false,"given":"Stephen","family":"Barnard","sequence":"additional","affiliation":[{"name":"Cytogenetics Group of the Radiation, Chemical, Climate and Environmental Hazards Division, UK Health Security Agency, Chilton, Oxfordshire OX11 0RQ, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9457-2020","authenticated-orcid":false,"given":"Jochen","family":"Einbeck","sequence":"additional","affiliation":[{"name":"Department of Mathematical Sciences, Durham University, Durham DH1 3LE, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2025,8,6]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"413","DOI":"10.1093\/rpd\/nci699","article-title":"Luminescence dosimetry using building materials and personal objects","volume":"119","author":"Bailiff","year":"2006","journal-title":"Radiat. 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