{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2019:ND4G6IE766AE3FFCOER6EBUAZA","short_pith_number":"pith:ND4G6IE7","canonical_record":{"source":{"id":"1902.02631","kind":"arxiv","version":1},"metadata":{"license":"http://creativecommons.org/licenses/by/4.0/","primary_cat":"physics.med-ph","submitted_at":"2019-02-05T21:43:19Z","cross_cats_sorted":[],"title_canon_sha256":"6c5647a25fb0b51dbd87d02c56c9c10a7512cffd0040574a86261aeb99a4e2ca","abstract_canon_sha256":"3e1f86cad3539a8cdad3e2a40fa51d9bb7b83619daead01f2137d48a66db13af"},"schema_version":"1.0"},"canonical_sha256":"68f86f209ff7804d94a27123e20680c81c20b4e287857ada5d8306e03936cbd2","source":{"kind":"arxiv","id":"1902.02631","version":1},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1902.02631","created_at":"2026-05-17T23:54:32Z"},{"alias_kind":"arxiv_version","alias_value":"1902.02631v1","created_at":"2026-05-17T23:54:32Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1902.02631","created_at":"2026-05-17T23:54:32Z"},{"alias_kind":"pith_short_12","alias_value":"ND4G6IE766AE","created_at":"2026-05-18T12:33:24Z"},{"alias_kind":"pith_short_16","alias_value":"ND4G6IE766AE3FFC","created_at":"2026-05-18T12:33:24Z"},{"alias_kind":"pith_short_8","alias_value":"ND4G6IE7","created_at":"2026-05-18T12:33:24Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2019:ND4G6IE766AE3FFCOER6EBUAZA","target":"record","payload":{"canonical_record":{"source":{"id":"1902.02631","kind":"arxiv","version":1},"metadata":{"license":"http://creativecommons.org/licenses/by/4.0/","primary_cat":"physics.med-ph","submitted_at":"2019-02-05T21:43:19Z","cross_cats_sorted":[],"title_canon_sha256":"6c5647a25fb0b51dbd87d02c56c9c10a7512cffd0040574a86261aeb99a4e2ca","abstract_canon_sha256":"3e1f86cad3539a8cdad3e2a40fa51d9bb7b83619daead01f2137d48a66db13af"},"schema_version":"1.0"},"canonical_sha256":"68f86f209ff7804d94a27123e20680c81c20b4e287857ada5d8306e03936cbd2","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-17T23:54:32.657524Z","signature_b64":"7S/4eEimqUjS1FeqgnbRcmDwYJlW8MJzRjgat1H9HMsLtNH9Lzyw65wowI7S/rC41b+jmhIGJzU+idHkiid/CA==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"68f86f209ff7804d94a27123e20680c81c20b4e287857ada5d8306e03936cbd2","last_reissued_at":"2026-05-17T23:54:32.656894Z","signature_status":"signed_v1","first_computed_at":"2026-05-17T23:54:32.656894Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"1902.02631","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":"2026-05-17T23:54:32Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"NhtDwfezhrEuUuwdPHtHhjIQlcU6POvl4s6eoSRWGUJsxKelX3zErtSIz4Qq618I06a8inQdctwx9cCmdN6gBA==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-06-06T18:09:00.415672Z"},"content_sha256":"5197c3c634e447f9e557033069054230f7493256c52a6742c49e2f985cc817a7","schema_version":"1.0","event_id":"sha256:5197c3c634e447f9e557033069054230f7493256c52a6742c49e2f985cc817a7"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2019:ND4G6IE766AE3FFCOER6EBUAZA","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"3-D Super-Resolution Ultrasound (SR-US) Imaging using a 2-D Sparse Array with High Volumetric Imaging Rate","license":"http://creativecommons.org/licenses/by/4.0/","headline":"","cross_cats":[],"primary_cat":"physics.med-ph","authors_text":"A. Ramalli, C. Dunsby, C.H. Leow, E. Boni, G. Zhang, J. Brown, J. Zhu, K. Christensen-Jeffries, M. Toulemonde, M-X. Tang, P. Tortoli, R.J. Eckersley, S. Harput","submitted_at":"2019-02-05T21:43:19Z","abstract_excerpt":"Super-resolution ultrasound imaging has been so far achieved in 3-D by mechanically scanning a volume with a linear probe, by co-aligning multiple linear probes, by using multiplexed 3-D clinical ultrasound systems, or by using 3-D ultrasound research systems. In this study, a 2-D sparse array was designed with 512 elements according to a density-tapered 2-D spiral layout and optimized to reduce the sidelobes of the transmitted beam profile. High frame rate volumetric imaging with compounded plane waves was performed using two synchronized ULA-OP 256 systems. Localization-based 3-D super-resol"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1902.02631","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":""},"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":"2026-05-17T23:54:32Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"jQKTxXia0ev6OJcjFsARIXQNuRV/VOji/MEKi/uTb2/LXyYEvUOAkhbrjK1wrGERwHr21BFQxDiFLvrVp43aDg==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-06-06T18:09:00.416120Z"},"content_sha256":"67f569df4f0c1d591b93451ad0052718e57d90fcf4283e6badd899952b2955bb","schema_version":"1.0","event_id":"sha256:67f569df4f0c1d591b93451ad0052718e57d90fcf4283e6badd899952b2955bb"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/ND4G6IE766AE3FFCOER6EBUAZA/bundle.json","state_url":"https://pith.science/pith/ND4G6IE766AE3FFCOER6EBUAZA/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/ND4G6IE766AE3FFCOER6EBUAZA/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":"2026-06-06T18:09:00Z","links":{"resolver":"https://pith.science/pith/ND4G6IE766AE3FFCOER6EBUAZA","bundle":"https://pith.science/pith/ND4G6IE766AE3FFCOER6EBUAZA/bundle.json","state":"https://pith.science/pith/ND4G6IE766AE3FFCOER6EBUAZA/state.json","well_known_bundle":"https://pith.science/.well-known/pith/ND4G6IE766AE3FFCOER6EBUAZA/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2019:ND4G6IE766AE3FFCOER6EBUAZA","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":"3e1f86cad3539a8cdad3e2a40fa51d9bb7b83619daead01f2137d48a66db13af","cross_cats_sorted":[],"license":"http://creativecommons.org/licenses/by/4.0/","primary_cat":"physics.med-ph","submitted_at":"2019-02-05T21:43:19Z","title_canon_sha256":"6c5647a25fb0b51dbd87d02c56c9c10a7512cffd0040574a86261aeb99a4e2ca"},"schema_version":"1.0","source":{"id":"1902.02631","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1902.02631","created_at":"2026-05-17T23:54:32Z"},{"alias_kind":"arxiv_version","alias_value":"1902.02631v1","created_at":"2026-05-17T23:54:32Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1902.02631","created_at":"2026-05-17T23:54:32Z"},{"alias_kind":"pith_short_12","alias_value":"ND4G6IE766AE","created_at":"2026-05-18T12:33:24Z"},{"alias_kind":"pith_short_16","alias_value":"ND4G6IE766AE3FFC","created_at":"2026-05-18T12:33:24Z"},{"alias_kind":"pith_short_8","alias_value":"ND4G6IE7","created_at":"2026-05-18T12:33:24Z"}],"graph_snapshots":[{"event_id":"sha256:67f569df4f0c1d591b93451ad0052718e57d90fcf4283e6badd899952b2955bb","target":"graph","created_at":"2026-05-17T23:54:32Z","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"},"paper":{"abstract_excerpt":"Super-resolution ultrasound imaging has been so far achieved in 3-D by mechanically scanning a volume with a linear probe, by co-aligning multiple linear probes, by using multiplexed 3-D clinical ultrasound systems, or by using 3-D ultrasound research systems. In this study, a 2-D sparse array was designed with 512 elements according to a density-tapered 2-D spiral layout and optimized to reduce the sidelobes of the transmitted beam profile. High frame rate volumetric imaging with compounded plane waves was performed using two synchronized ULA-OP 256 systems. Localization-based 3-D super-resol","authors_text":"A. Ramalli, C. Dunsby, C.H. Leow, E. Boni, G. Zhang, J. Brown, J. Zhu, K. Christensen-Jeffries, M. Toulemonde, M-X. Tang, P. Tortoli, R.J. Eckersley, S. Harput","cross_cats":[],"headline":"","license":"http://creativecommons.org/licenses/by/4.0/","primary_cat":"physics.med-ph","submitted_at":"2019-02-05T21:43:19Z","title":"3-D Super-Resolution Ultrasound (SR-US) Imaging using a 2-D Sparse Array with High Volumetric Imaging Rate"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1902.02631","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":"sha256:5197c3c634e447f9e557033069054230f7493256c52a6742c49e2f985cc817a7","target":"record","created_at":"2026-05-17T23:54:32Z","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":"3e1f86cad3539a8cdad3e2a40fa51d9bb7b83619daead01f2137d48a66db13af","cross_cats_sorted":[],"license":"http://creativecommons.org/licenses/by/4.0/","primary_cat":"physics.med-ph","submitted_at":"2019-02-05T21:43:19Z","title_canon_sha256":"6c5647a25fb0b51dbd87d02c56c9c10a7512cffd0040574a86261aeb99a4e2ca"},"schema_version":"1.0","source":{"id":"1902.02631","kind":"arxiv","version":1}},"canonical_sha256":"68f86f209ff7804d94a27123e20680c81c20b4e287857ada5d8306e03936cbd2","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"68f86f209ff7804d94a27123e20680c81c20b4e287857ada5d8306e03936cbd2","first_computed_at":"2026-05-17T23:54:32.656894Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-17T23:54:32.656894Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"7S/4eEimqUjS1FeqgnbRcmDwYJlW8MJzRjgat1H9HMsLtNH9Lzyw65wowI7S/rC41b+jmhIGJzU+idHkiid/CA==","signature_status":"signed_v1","signed_at":"2026-05-17T23:54:32.657524Z","signed_message":"canonical_sha256_bytes"},"source_id":"1902.02631","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:5197c3c634e447f9e557033069054230f7493256c52a6742c49e2f985cc817a7","sha256:67f569df4f0c1d591b93451ad0052718e57d90fcf4283e6badd899952b2955bb"],"state_sha256":"590e9c0b8cbbe6f23210c24ba9526724ed946fd2c3e26e7770772bc425a16293"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"LW+PWwmWLOR9aIE5CZwCfGyB4ApWWF8htvyuGoFnbR4+Vi8SiC/ItClZSczYXUQHy+GDgTxSw//6trNS+EWvAQ==","signed_message":"bundle_sha256_bytes","signed_at":"2026-06-06T18:09:00.419711Z","bundle_sha256":"12ef86d29c9768a462dddecba25b9bf456c0b2ffa12bdc4cd1f2f8cf3ad4d9b7"}}