{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2018:JKXCJUKEJT7IYISLAAIIW5IXNS","short_pith_number":"pith:JKXCJUKE","canonical_record":{"source":{"id":"1804.07436","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cs.CV","submitted_at":"2018-04-20T03:13:27Z","cross_cats_sorted":[],"title_canon_sha256":"e6f418aa4b372a811e86ba1c5940fd653b4f8296880b5b163520b571738467ac","abstract_canon_sha256":"ee2771b2c0b19ad468cdcdfea79c4a13360f78594171b6f2eb1ba9e5c1236d4c"},"schema_version":"1.0"},"canonical_sha256":"4aae24d1444cfe8c224b00108b75176c917475dadb3dde457229ce47c5bf7f76","source":{"kind":"arxiv","id":"1804.07436","version":1},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1804.07436","created_at":"2026-05-18T00:17:58Z"},{"alias_kind":"arxiv_version","alias_value":"1804.07436v1","created_at":"2026-05-18T00:17:58Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1804.07436","created_at":"2026-05-18T00:17:58Z"},{"alias_kind":"pith_short_12","alias_value":"JKXCJUKEJT7I","created_at":"2026-05-18T12:32:31Z"},{"alias_kind":"pith_short_16","alias_value":"JKXCJUKEJT7IYISL","created_at":"2026-05-18T12:32:31Z"},{"alias_kind":"pith_short_8","alias_value":"JKXCJUKE","created_at":"2026-05-18T12:32:31Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2018:JKXCJUKEJT7IYISLAAIIW5IXNS","target":"record","payload":{"canonical_record":{"source":{"id":"1804.07436","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cs.CV","submitted_at":"2018-04-20T03:13:27Z","cross_cats_sorted":[],"title_canon_sha256":"e6f418aa4b372a811e86ba1c5940fd653b4f8296880b5b163520b571738467ac","abstract_canon_sha256":"ee2771b2c0b19ad468cdcdfea79c4a13360f78594171b6f2eb1ba9e5c1236d4c"},"schema_version":"1.0"},"canonical_sha256":"4aae24d1444cfe8c224b00108b75176c917475dadb3dde457229ce47c5bf7f76","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-18T00:17:58.820083Z","signature_b64":"OvxAUU+e6bqQmXgOxfzzDegLLIAN+XtBDjWJeJGJMxTv25+8b3FGsVwGo0b+de6zd1jqfISPMgDOpy06xssWAQ==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"4aae24d1444cfe8c224b00108b75176c917475dadb3dde457229ce47c5bf7f76","last_reissued_at":"2026-05-18T00:17:58.819380Z","signature_status":"signed_v1","first_computed_at":"2026-05-18T00:17:58.819380Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"1804.07436","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":"2026-05-18T00:17:58Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"VWBT4P2VzMwG6w5jZs4Yw8a2m43/L5Ki6kelnGb0U4qY7Mfm8Jj1hx0C9Pg0ABk1dLFQiivmr5X0aYH+tTGOAA==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-06-22T07:05:39.015362Z"},"content_sha256":"ecf0f695237b208d94f6aaee7a44924ad7f4895532cc09d7de187f195b483ba9","schema_version":"1.0","event_id":"sha256:ecf0f695237b208d94f6aaee7a44924ad7f4895532cc09d7de187f195b483ba9"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2018:JKXCJUKEJT7IYISLAAIIW5IXNS","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"Calibration-free B0 correction of EPI data using structured low rank matrix recovery","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"cs.CV","authors_text":"Arvind Balachandrasekaran, Mathews Jacob, Merry Mani","submitted_at":"2018-04-20T03:13:27Z","abstract_excerpt":"We introduce a structured low rank algorithm for the calibration-free compensation of field inhomogeneity artifacts in Echo Planar Imaging (EPI) MRI data. We acquire the data using two EPI readouts that differ in echo-time (TE). Using time segmentation, we reformulate the field inhomogeneity compensation problem as the recovery of an image time series from highly undersampled Fourier measurements. The temporal profile at each pixel is modeled as a single exponential, which is exploited to fill in the missing entries. We show that the exponential behavior at each pixel, along with the spatial s"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1804.07436","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":"2026-05-18T00:17:58Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"rG76Hi7ASxqJPWpBjINEfgGasyxieByVQtnN418nKAICJFGK/yA60k4hDdMVuDhYmcYObUgqbSGY5gRYla2oAw==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-06-22T07:05:39.015726Z"},"content_sha256":"c7c43fa3c30ce69327306c3e71a51cf5fc9b53ef303056251ea406f23b9407db","schema_version":"1.0","event_id":"sha256:c7c43fa3c30ce69327306c3e71a51cf5fc9b53ef303056251ea406f23b9407db"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/JKXCJUKEJT7IYISLAAIIW5IXNS/bundle.json","state_url":"https://pith.science/pith/JKXCJUKEJT7IYISLAAIIW5IXNS/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/JKXCJUKEJT7IYISLAAIIW5IXNS/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":"2026-06-22T07:05:39Z","links":{"resolver":"https://pith.science/pith/JKXCJUKEJT7IYISLAAIIW5IXNS","bundle":"https://pith.science/pith/JKXCJUKEJT7IYISLAAIIW5IXNS/bundle.json","state":"https://pith.science/pith/JKXCJUKEJT7IYISLAAIIW5IXNS/state.json","well_known_bundle":"https://pith.science/.well-known/pith/JKXCJUKEJT7IYISLAAIIW5IXNS/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2018:JKXCJUKEJT7IYISLAAIIW5IXNS","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":"ee2771b2c0b19ad468cdcdfea79c4a13360f78594171b6f2eb1ba9e5c1236d4c","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cs.CV","submitted_at":"2018-04-20T03:13:27Z","title_canon_sha256":"e6f418aa4b372a811e86ba1c5940fd653b4f8296880b5b163520b571738467ac"},"schema_version":"1.0","source":{"id":"1804.07436","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1804.07436","created_at":"2026-05-18T00:17:58Z"},{"alias_kind":"arxiv_version","alias_value":"1804.07436v1","created_at":"2026-05-18T00:17:58Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1804.07436","created_at":"2026-05-18T00:17:58Z"},{"alias_kind":"pith_short_12","alias_value":"JKXCJUKEJT7I","created_at":"2026-05-18T12:32:31Z"},{"alias_kind":"pith_short_16","alias_value":"JKXCJUKEJT7IYISL","created_at":"2026-05-18T12:32:31Z"},{"alias_kind":"pith_short_8","alias_value":"JKXCJUKE","created_at":"2026-05-18T12:32:31Z"}],"graph_snapshots":[{"event_id":"sha256:c7c43fa3c30ce69327306c3e71a51cf5fc9b53ef303056251ea406f23b9407db","target":"graph","created_at":"2026-05-18T00:17:58Z","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":"We introduce a structured low rank algorithm for the calibration-free compensation of field inhomogeneity artifacts in Echo Planar Imaging (EPI) MRI data. We acquire the data using two EPI readouts that differ in echo-time (TE). Using time segmentation, we reformulate the field inhomogeneity compensation problem as the recovery of an image time series from highly undersampled Fourier measurements. The temporal profile at each pixel is modeled as a single exponential, which is exploited to fill in the missing entries. We show that the exponential behavior at each pixel, along with the spatial s","authors_text":"Arvind Balachandrasekaran, Mathews Jacob, Merry Mani","cross_cats":[],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cs.CV","submitted_at":"2018-04-20T03:13:27Z","title":"Calibration-free B0 correction of EPI data using structured low rank matrix recovery"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1804.07436","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:ecf0f695237b208d94f6aaee7a44924ad7f4895532cc09d7de187f195b483ba9","target":"record","created_at":"2026-05-18T00:17:58Z","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":"ee2771b2c0b19ad468cdcdfea79c4a13360f78594171b6f2eb1ba9e5c1236d4c","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cs.CV","submitted_at":"2018-04-20T03:13:27Z","title_canon_sha256":"e6f418aa4b372a811e86ba1c5940fd653b4f8296880b5b163520b571738467ac"},"schema_version":"1.0","source":{"id":"1804.07436","kind":"arxiv","version":1}},"canonical_sha256":"4aae24d1444cfe8c224b00108b75176c917475dadb3dde457229ce47c5bf7f76","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"4aae24d1444cfe8c224b00108b75176c917475dadb3dde457229ce47c5bf7f76","first_computed_at":"2026-05-18T00:17:58.819380Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-18T00:17:58.819380Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"OvxAUU+e6bqQmXgOxfzzDegLLIAN+XtBDjWJeJGJMxTv25+8b3FGsVwGo0b+de6zd1jqfISPMgDOpy06xssWAQ==","signature_status":"signed_v1","signed_at":"2026-05-18T00:17:58.820083Z","signed_message":"canonical_sha256_bytes"},"source_id":"1804.07436","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:ecf0f695237b208d94f6aaee7a44924ad7f4895532cc09d7de187f195b483ba9","sha256:c7c43fa3c30ce69327306c3e71a51cf5fc9b53ef303056251ea406f23b9407db"],"state_sha256":"cab03fb1148a3d5ce8d2878457af98f4633fcd429dc1e211888ad00f58ce4718"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"dvXQ2RsRQ2dnO4DaF3E+YPgoujiA8OcKJUAN7n1+DOKbZvtAbgaXYo3PZKvdonjX1g8KCjYzpnwDy/aRy1GFDw==","signed_message":"bundle_sha256_bytes","signed_at":"2026-06-22T07:05:39.017791Z","bundle_sha256":"6224bb52e55453d6cb741ff672098a526d2da4a83b6ad98a5d76b92f7d9a18ab"}}