{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2026:2BQEGVDDOWAXBB2XWQQSWH7WJT","short_pith_number":"pith:2BQEGVDD","canonical_record":{"source":{"id":"2607.28771","kind":"arxiv","version":1},"metadata":{"license":"http://creativecommons.org/licenses/by/4.0/","primary_cat":"cs.CV","submitted_at":"2026-07-30T18:46:57Z","cross_cats_sorted":[],"title_canon_sha256":"d222dac49b8afd7e3d627034ddf8baf8bffa1bb1966ef13153c3cb2f0594171b","abstract_canon_sha256":"4161eb29bd604b5457500fb7bf6fd91411833b7bc1b1e3bee6707c5b78747c84"},"schema_version":"1.0"},"canonical_sha256":"d0604354637581708757b4212b1ff64cf61cd0f19e7679be5c2bc9d6ff6d78d9","source":{"kind":"arxiv","id":"2607.28771","version":1},"source_aliases":[{"alias_kind":"arxiv","alias_value":"2607.28771","created_at":"2026-08-03T00:12:50Z"},{"alias_kind":"arxiv_version","alias_value":"2607.28771v1","created_at":"2026-08-03T00:12:50Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.2607.28771","created_at":"2026-08-03T00:12:50Z"},{"alias_kind":"pith_short_12","alias_value":"2BQEGVDDOWAX","created_at":"2026-08-03T00:12:50Z"},{"alias_kind":"pith_short_16","alias_value":"2BQEGVDDOWAXBB2X","created_at":"2026-08-03T00:12:50Z"},{"alias_kind":"pith_short_8","alias_value":"2BQEGVDD","created_at":"2026-08-03T00:12:50Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2026:2BQEGVDDOWAXBB2XWQQSWH7WJT","target":"record","payload":{"canonical_record":{"source":{"id":"2607.28771","kind":"arxiv","version":1},"metadata":{"license":"http://creativecommons.org/licenses/by/4.0/","primary_cat":"cs.CV","submitted_at":"2026-07-30T18:46:57Z","cross_cats_sorted":[],"title_canon_sha256":"d222dac49b8afd7e3d627034ddf8baf8bffa1bb1966ef13153c3cb2f0594171b","abstract_canon_sha256":"4161eb29bd604b5457500fb7bf6fd91411833b7bc1b1e3bee6707c5b78747c84"},"schema_version":"1.0"},"canonical_sha256":"d0604354637581708757b4212b1ff64cf61cd0f19e7679be5c2bc9d6ff6d78d9","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-08-03T00:12:50.474064Z","signature_b64":"HgMX4wjXvFQqktawppzOhWhVuPshi9yslOsrEKNu2/RZtw1o2Qt0zpRCqQCj0xPhX48/X+8tTFEhf8MenUAIAA==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"d0604354637581708757b4212b1ff64cf61cd0f19e7679be5c2bc9d6ff6d78d9","last_reissued_at":"2026-08-03T00:12:50.471922Z","signature_status":"signed_v1","first_computed_at":"2026-08-03T00:12:50.471922Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"2607.28771","source_version":1,"attestation_state":"computed"},"signer":{"signer_id":"pith.science","signer_type":"pith_registry","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"created_at":"2026-08-03T00:12:50Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"cRc+oRuSxvmBHsIk3l6qeTXUbocl6R4gnv0PqhDxET6nh6fB0CxK2mVW1VNINEw1GMxOFlmtcNsRQQRL4uFSAA==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-08-06T07:26:12.101554Z"},"content_sha256":"b5484710702dafd7d34f7651282f4f933a594137456c5e0d9b6959b15515f880","schema_version":"1.0","event_id":"sha256:b5484710702dafd7d34f7651282f4f933a594137456c5e0d9b6959b15515f880"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2026:2BQEGVDDOWAXBB2XWQQSWH7WJT","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"Do Medical Foundation Models Generalize on the African Brain?","license":"http://creativecommons.org/licenses/by/4.0/","headline":"","cross_cats":[],"primary_cat":"cs.CV","authors_text":"Esther E. Bron, Gonzalo Esteban Mosquera Rojas, Juancito van Leeuwen, Kaouther Mouheb, Stefan Klein","submitted_at":"2026-07-30T18:46:57Z","abstract_excerpt":"Medical foundation models (FMs) are increasingly used for brain MRI analysis. However, their evaluation remains dominated by high-resource datasets, leaving generalization to African cohorts underexplored. We assess whether FMs generalize equally to African and non-African brain MRI data across two tasks: dementia classification using a Nigerian dataset and brain tumor segmentation using BraTS-Africa. We evaluate two generalist FMs (BrainIAC, 3DINO) and two segmentation-specific FMs (MedSAM2, Medical-SAM2) against a from-scratch baseline. For classification, FMs provide limited gains (highest "},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"2607.28771","kind":"arxiv","version":1},"verdict":{"id":null,"model_set":{},"created_at":null,"strongest_claim":"","one_line_summary":"","pipeline_version":null,"weakest_assumption":"","pith_extraction_headline":""},"integrity":{"clean":true,"summary":{"advisory":0,"critical":0,"by_detector":{},"informational":0},"endpoint":"/pith/2607.28771/integrity.json","findings":[],"available":true,"detectors_run":[],"snapshot_sha256":"c28c3603d3b5d939e8dc4c7e95fa8dfce3d595e45f758748cecf8e644a296938"},"references":{"count":0,"sample":[],"resolved_work":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57","internal_anchors":0},"formal_canon":{"evidence_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"author_claims":{"count":0,"strong_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"builder_version":"pith-number-builder-2026-05-17-v1"},"verdict_id":null},"signer":{"signer_id":"pith.science","signer_type":"pith_registry","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"created_at":"2026-08-03T00:12:50Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"oHzOKckTWaL1fIHQN+BbJAyWNP2RW4oj3c5yGkXGm0oFkB14NsQwLF2zMWyiobDO4dwX/boAG0j0sAg2QCANAQ==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-08-06T07:26:12.102052Z"},"content_sha256":"c0e67a0b698c2d8c8f4b7a6109e30f04bd307e7695fee28df346bcbe924b845d","schema_version":"1.0","event_id":"sha256:c0e67a0b698c2d8c8f4b7a6109e30f04bd307e7695fee28df346bcbe924b845d"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/2BQEGVDDOWAXBB2XWQQSWH7WJT/bundle.json","state_url":"https://pith.science/pith/2BQEGVDDOWAXBB2XWQQSWH7WJT/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/2BQEGVDDOWAXBB2XWQQSWH7WJT/bundle.json","status":"primary"}],"public_keys":[{"key_id":"pith-v1-2026-05","algorithm":"ed25519","format":"raw","public_key_b64":"stVStoiQhXFxp4s2pdzPNoqVNBMojDU/fJ2db5S3CbM=","public_key_hex":"b2d552b68890857171a78b36a5dccf368a953413288c353f7c9d9d6f94b709b3","fingerprint_sha256_b32_first128bits":"RVFV5Z2OI2J3ZUO7ERDEBCYNKS","fingerprint_sha256_hex":"8d4b5ee74e4693bcd1df2446408b0d54","rotates_at":null,"url":"https://pith.science/pith-signing-key.json","notes":"Pith uses this Ed25519 key to sign canonical record SHA-256 digests. Verify with: ed25519_verify(public_key, message=canonical_sha256_bytes, signature=base64decode(signature_b64))."}],"merge_version":"pith-open-graph-merge-v1","built_at":"2026-08-06T07:26:12Z","links":{"resolver":"https://pith.science/pith/2BQEGVDDOWAXBB2XWQQSWH7WJT","bundle":"https://pith.science/pith/2BQEGVDDOWAXBB2XWQQSWH7WJT/bundle.json","state":"https://pith.science/pith/2BQEGVDDOWAXBB2XWQQSWH7WJT/state.json","well_known_bundle":"https://pith.science/.well-known/pith/2BQEGVDDOWAXBB2XWQQSWH7WJT/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2026:2BQEGVDDOWAXBB2XWQQSWH7WJT","merge_version":"pith-open-graph-merge-v1","event_count":2,"valid_event_count":2,"invalid_event_count":0,"equivocation_count":0,"current":{"canonical_record":{"metadata":{"abstract_canon_sha256":"4161eb29bd604b5457500fb7bf6fd91411833b7bc1b1e3bee6707c5b78747c84","cross_cats_sorted":[],"license":"http://creativecommons.org/licenses/by/4.0/","primary_cat":"cs.CV","submitted_at":"2026-07-30T18:46:57Z","title_canon_sha256":"d222dac49b8afd7e3d627034ddf8baf8bffa1bb1966ef13153c3cb2f0594171b"},"schema_version":"1.0","source":{"id":"2607.28771","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"2607.28771","created_at":"2026-08-03T00:12:50Z"},{"alias_kind":"arxiv_version","alias_value":"2607.28771v1","created_at":"2026-08-03T00:12:50Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.2607.28771","created_at":"2026-08-03T00:12:50Z"},{"alias_kind":"pith_short_12","alias_value":"2BQEGVDDOWAX","created_at":"2026-08-03T00:12:50Z"},{"alias_kind":"pith_short_16","alias_value":"2BQEGVDDOWAXBB2X","created_at":"2026-08-03T00:12:50Z"},{"alias_kind":"pith_short_8","alias_value":"2BQEGVDD","created_at":"2026-08-03T00:12:50Z"}],"graph_snapshots":[{"event_id":"sha256:c0e67a0b698c2d8c8f4b7a6109e30f04bd307e7695fee28df346bcbe924b845d","target":"graph","created_at":"2026-08-03T00:12:50Z","signer":{"key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signer_id":"pith.science","signer_type":"pith_registry"},"payload":{"graph_snapshot":{"author_claims":{"count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57","strong_count":0},"builder_version":"pith-number-builder-2026-05-17-v1","claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"formal_canon":{"evidence_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"integrity":{"available":true,"clean":true,"detectors_run":[],"endpoint":"/pith/2607.28771/integrity.json","findings":[],"snapshot_sha256":"c28c3603d3b5d939e8dc4c7e95fa8dfce3d595e45f758748cecf8e644a296938","summary":{"advisory":0,"by_detector":{},"critical":0,"informational":0}},"paper":{"abstract_excerpt":"Medical foundation models (FMs) are increasingly used for brain MRI analysis. However, their evaluation remains dominated by high-resource datasets, leaving generalization to African cohorts underexplored. We assess whether FMs generalize equally to African and non-African brain MRI data across two tasks: dementia classification using a Nigerian dataset and brain tumor segmentation using BraTS-Africa. We evaluate two generalist FMs (BrainIAC, 3DINO) and two segmentation-specific FMs (MedSAM2, Medical-SAM2) against a from-scratch baseline. For classification, FMs provide limited gains (highest ","authors_text":"Esther E. Bron, Gonzalo Esteban Mosquera Rojas, Juancito van Leeuwen, Kaouther Mouheb, Stefan Klein","cross_cats":[],"headline":"","license":"http://creativecommons.org/licenses/by/4.0/","primary_cat":"cs.CV","submitted_at":"2026-07-30T18:46:57Z","title":"Do Medical Foundation Models Generalize on the African Brain?"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"2607.28771","kind":"arxiv","version":1},"verdict":{"created_at":null,"id":null,"model_set":{},"one_line_summary":"","pipeline_version":null,"pith_extraction_headline":"","strongest_claim":"","weakest_assumption":""}},"verdict_id":null}}],"author_attestations":[],"timestamp_anchors":[],"storage_attestations":[],"citation_signatures":[],"replication_records":[],"corrections":[],"mirror_hints":[],"record_created":{"event_id":"sha256:b5484710702dafd7d34f7651282f4f933a594137456c5e0d9b6959b15515f880","target":"record","created_at":"2026-08-03T00:12:50Z","signer":{"key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signer_id":"pith.science","signer_type":"pith_registry"},"payload":{"attestation_state":"computed","canonical_record":{"metadata":{"abstract_canon_sha256":"4161eb29bd604b5457500fb7bf6fd91411833b7bc1b1e3bee6707c5b78747c84","cross_cats_sorted":[],"license":"http://creativecommons.org/licenses/by/4.0/","primary_cat":"cs.CV","submitted_at":"2026-07-30T18:46:57Z","title_canon_sha256":"d222dac49b8afd7e3d627034ddf8baf8bffa1bb1966ef13153c3cb2f0594171b"},"schema_version":"1.0","source":{"id":"2607.28771","kind":"arxiv","version":1}},"canonical_sha256":"d0604354637581708757b4212b1ff64cf61cd0f19e7679be5c2bc9d6ff6d78d9","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"d0604354637581708757b4212b1ff64cf61cd0f19e7679be5c2bc9d6ff6d78d9","first_computed_at":"2026-08-03T00:12:50.471922Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-08-03T00:12:50.471922Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"HgMX4wjXvFQqktawppzOhWhVuPshi9yslOsrEKNu2/RZtw1o2Qt0zpRCqQCj0xPhX48/X+8tTFEhf8MenUAIAA==","signature_status":"signed_v1","signed_at":"2026-08-03T00:12:50.474064Z","signed_message":"canonical_sha256_bytes"},"source_id":"2607.28771","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:b5484710702dafd7d34f7651282f4f933a594137456c5e0d9b6959b15515f880","sha256:c0e67a0b698c2d8c8f4b7a6109e30f04bd307e7695fee28df346bcbe924b845d"],"state_sha256":"0580651daf14c9dddd515ea8af31280c13c85dbe7277606be0f62d54b268cfdc"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"0C+35WJ7uOsfEtnbRTh/wPbtcvKTdSqgzii4btOYXvsLj32a4zZInXl+7ktOSz+FPXYUpqv2QhItuO92TZTMDw==","signed_message":"bundle_sha256_bytes","signed_at":"2026-08-06T07:26:12.105488Z","bundle_sha256":"15f151c1537adf2789615c36b70f12f72c54fddd41ef988d9626aa01ac33e89b"}}