{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2021:T75M5PEUEIVGN4T5AIBO5BCJ5P","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":"1375dac4fddc5d7c10b791df707897a06c20b678a50cbde1ac200d5b41373c30","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"physics.med-ph","submitted_at":"2021-02-10T08:35:51Z","title_canon_sha256":"25f75f45eba93dce6cf677794e67c39e6ec39c47369559ec8c63045feb93a700"},"schema_version":"1.0","source":{"id":"2102.05318","kind":"arxiv","version":2}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"2102.05318","created_at":"2026-07-05T02:14:33Z"},{"alias_kind":"arxiv_version","alias_value":"2102.05318v2","created_at":"2026-07-05T02:14:33Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.2102.05318","created_at":"2026-07-05T02:14:33Z"},{"alias_kind":"pith_short_12","alias_value":"T75M5PEUEIVG","created_at":"2026-07-05T02:14:33Z"},{"alias_kind":"pith_short_16","alias_value":"T75M5PEUEIVGN4T5","created_at":"2026-07-05T02:14:33Z"},{"alias_kind":"pith_short_8","alias_value":"T75M5PEU","created_at":"2026-07-05T02:14:33Z"}],"graph_snapshots":[{"event_id":"sha256:7a54c17c73ee34bf2f23f412f443ff06fbdeeefc3016ab9fb9868604538c3725","target":"graph","created_at":"2026-07-05T02:14:33Z","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/2102.05318/integrity.json","findings":[],"snapshot_sha256":"c28c3603d3b5d939e8dc4c7e95fa8dfce3d595e45f758748cecf8e644a296938","summary":{"advisory":0,"by_detector":{},"critical":0,"informational":0}},"paper":{"abstract_excerpt":"Attenuation compensation (AC) is a pre-requisite for reliable quantification and beneficial for visual interpretation tasks in single-photon emission computed tomography (SPECT). Typical AC methods require the availability of an attenuation map obtained using a transmission scan, such as a CT scan. This has several disadvantages such as increased radiation dose, higher costs, and possible misalignment between SPECT and CT scans. Also, often a CT scan is unavailable. In this context, we and others are showing that scattered photons in SPECT contain information to estimate the attenuation distri","authors_text":"Abhinav K. Jha, Md Ashequr Rahman, Richard Laforest, Thomas Schindler, Zitong Yu","cross_cats":[],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"physics.med-ph","submitted_at":"2021-02-10T08:35:51Z","title":"A physics and learning-based transmission-less attenuation compensation method for SPECT"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"2102.05318","kind":"arxiv","version":2},"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:b8e071914de8a4e7908eb92e6699115177cb1f5324ad01ee260687863f5a1894","target":"record","created_at":"2026-07-05T02:14:33Z","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":"1375dac4fddc5d7c10b791df707897a06c20b678a50cbde1ac200d5b41373c30","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"physics.med-ph","submitted_at":"2021-02-10T08:35:51Z","title_canon_sha256":"25f75f45eba93dce6cf677794e67c39e6ec39c47369559ec8c63045feb93a700"},"schema_version":"1.0","source":{"id":"2102.05318","kind":"arxiv","version":2}},"canonical_sha256":"9ffacebc94222a66f27d0202ee8449ebe91d5c6a72a418c5af6b60b30e6648ed","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"9ffacebc94222a66f27d0202ee8449ebe91d5c6a72a418c5af6b60b30e6648ed","first_computed_at":"2026-07-05T02:14:33.662739Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-07-05T02:14:33.662739Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"Yj2WAPzHBKmSUWq5+k/8l82homG2nJwDFLGYIlmz+PkVbgjO3oswm+IEFlcn/SOlQVW6UQZgmC4nuZ0/5HcHBw==","signature_status":"signed_v1","signed_at":"2026-07-05T02:14:33.663119Z","signed_message":"canonical_sha256_bytes"},"source_id":"2102.05318","source_kind":"arxiv","source_version":2}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:b8e071914de8a4e7908eb92e6699115177cb1f5324ad01ee260687863f5a1894","sha256:7a54c17c73ee34bf2f23f412f443ff06fbdeeefc3016ab9fb9868604538c3725"],"state_sha256":"2bf3c59abcaa2fffdfd8f8c3653bd78f9c8e3dcdbc58bff74a428b3e758f0e16"}