{"record":{"author":{"account_ref":null,"orcid":null},"builds_on":[],"content_schema":"pubphys.content.topic/1","content_sha256":"f0170d321ea822371c8e76dc0c9e191e5af21f54bba4225feb1e2ce768ffe2ab","created":"2026-10-03T07:17:52Z","files":[],"origin":{"assisted_by":[],"kind":"seed"},"parents":[],"salt":"32c871e435a859aa0a650a0b237f5a5519476900ef4665b8e01cbdf60152c7b9","schema":"pubphys.record/2","site":"pubphys.com","target":null,"type":"topic"},"content":{"external_id":"med.diffusion-mri","field":"med","n":"1","review_cite":"Novikov, Fieremans, Jespersen and Kiselev, Quantifying brain microstructure with diffusion MRI: Theory and parameter estimation, NMR in Biomedicine, 2019","review_link":"https://doi.org/10.1002/nbm.3998","review_verified":"true","summary":"Magnetic resonance scanners can track how water molecules wander inside tissue, and the wandering is slowed by cell walls and fibres far smaller than an image pixel. The open question is how much of the hidden microscopic structure can actually be read back from that signal.","title":"Diffusion MRI of tissue microstructure","topic_ref":null,"why":"Microstructure maps would give non-invasive measures of axon loss, tumour cellularity and tissue damage, but only if the inferred parameters are unique and correct."},"attested":{"attestation":{"batch":null,"client_id":null,"id_token_sha256":null,"kind":"platform"},"record_hash":"7d6543da8b95cbfe0f88251dd0987163345fc9bcbe4e99e44fdf7b56a0f8bcd0","schema":"pubphys.attested/1"},"envelope":{"attested_hash":"ce869c6932d1ac0e91c3594030d40d60258951646b2237ce550e55fa5ec91524","platform_signature":{"key_id":"c6afc19b31429869751f06879c75cd64ea92654423d15b44be775bf1310a60da","sig":"dP5RU2uZNpHSLNkqXD7Uhb5dt_qaqrwCLnO2U5hQZzd2bVdmZ5PznyPoH9DxnXLMSyRwXzkqxhZ2KD940yfVBw"},"schema":"pubphys.envelope/1"},"record_hash":"7d6543da8b95cbfe0f88251dd0987163345fc9bcbe4e99e44fdf7b56a0f8bcd0","leaf_index":269}