{"record":{"author":{"account_ref":null,"orcid":null},"builds_on":[],"content_schema":"pubphys.content.revision/1","content_sha256":"dba18063910b0e777ae131e1b25c2540f09fcb8f6abd5f281bae3d2fa46c701f","created":"2026-10-03T07:18:06Z","files":[],"origin":{"assisted_by":[],"kind":"seed"},"parents":["5475cf5dc5b1a72283d26dc95dc6e00d7ea4e00096a7c6492e409a1816eeb011"],"salt":"24522523837971580f5a8897c40f587a5e8ce636fbfad1d433d0a367c4e4bec6","schema":"pubphys.record/2","site":"pubphys.com","target":null,"type":"revision"},"content":{"answer_type":"value","assisted_by":[],"external_id":"med.bnct.boron-microdistribution","kind":"well-posed","literature_status":"open","n":"1","parents":[],"plain":"The capture fragments travel only about a cell diameter, so the dose depends on whether the boron is inside each cell or outside it. Measurements of this in patients are lacking.","posed_since":"","precise":"Measure the B-10 concentration distribution at 1 to 10 micron resolution in tumour, tumour margin and normal tissue for the clinical carriers (boronophenylalanine and sodium borocaptate), including the fraction of tumour cells with low uptake, and convert it into a microdosimetric specific-energy distribution for the $\\alpha$ and Li-7 fragments of ranges about 9 and 5 micron. An answer is a measured distribution and the resulting ratio of cellular to bulk-averaged dose.","problem_ref":null,"references":"","settled_by":"Neutron autoradiography or secondary-ion mass spectrometry on biopsy samples taken at treatment time, combined with track-level dose calculation.","status_note":"","title":"Cellular-scale boron distribution in tumour and normal tissue","topic_ref":"0c8039c980b31f825989ca36e1cd7529f5aab83d616e66638b0e9746fc03ac15"},"attested":{"attestation":{"batch":null,"client_id":null,"id_token_sha256":null,"kind":"platform"},"record_hash":"d294368893449ccc1ea088b9532ed292bf26d42c78fb19a62e93964356dc22fd","schema":"pubphys.attested/1"},"envelope":{"attested_hash":"25cd7d8189034893af514c13fa4c94ff5690e34d0665c44f6c111d9e24118aab","platform_signature":{"key_id":"c6afc19b31429869751f06879c75cd64ea92654423d15b44be775bf1310a60da","sig":"OwArNm3X8ZtJj0Vj8sD0kvDUNsmfrxZfjWH5WpQhNERUKwYuBXt1wg-TMw27MKvtBoV10qzx508VKKteh_WUDw"},"schema":"pubphys.envelope/1"},"record_hash":"d294368893449ccc1ea088b9532ed292bf26d42c78fb19a62e93964356dc22fd","leaf_index":1666}