{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2018:S6KKVY2FPLQEILHR6DAYYVGD5Z","short_pith_number":"pith:S6KKVY2F","canonical_record":{"source":{"id":"1809.08179","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"q-bio.TO","submitted_at":"2018-09-21T15:52:47Z","cross_cats_sorted":[],"title_canon_sha256":"8588f63d30dc4c0dd2b168c486b9af1132409d17a4e83e97d102c53a2c748391","abstract_canon_sha256":"52a480c6ea22f3174987a563f09b4c40681b16481520b2aa02351aaaac362a93"},"schema_version":"1.0"},"canonical_sha256":"9794aae3457ae0442cf1f0c18c54c3ee71154e04a74e89ebe3f748555a57921c","source":{"kind":"arxiv","id":"1809.08179","version":1},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1809.08179","created_at":"2026-05-18T00:05:10Z"},{"alias_kind":"arxiv_version","alias_value":"1809.08179v1","created_at":"2026-05-18T00:05:10Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1809.08179","created_at":"2026-05-18T00:05:10Z"},{"alias_kind":"pith_short_12","alias_value":"S6KKVY2FPLQE","created_at":"2026-05-18T12:32:50Z"},{"alias_kind":"pith_short_16","alias_value":"S6KKVY2FPLQEILHR","created_at":"2026-05-18T12:32:50Z"},{"alias_kind":"pith_short_8","alias_value":"S6KKVY2F","created_at":"2026-05-18T12:32:50Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2018:S6KKVY2FPLQEILHR6DAYYVGD5Z","target":"record","payload":{"canonical_record":{"source":{"id":"1809.08179","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"q-bio.TO","submitted_at":"2018-09-21T15:52:47Z","cross_cats_sorted":[],"title_canon_sha256":"8588f63d30dc4c0dd2b168c486b9af1132409d17a4e83e97d102c53a2c748391","abstract_canon_sha256":"52a480c6ea22f3174987a563f09b4c40681b16481520b2aa02351aaaac362a93"},"schema_version":"1.0"},"canonical_sha256":"9794aae3457ae0442cf1f0c18c54c3ee71154e04a74e89ebe3f748555a57921c","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-18T00:05:10.184812Z","signature_b64":"qazZydZTBxMMZV/Q32LqVyPdTsB9yK2ISIKXVnbrcGyXETkyMasQYTDNXmjHT2uw57w5U1tJ2R3QDD09r7P8BA==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"9794aae3457ae0442cf1f0c18c54c3ee71154e04a74e89ebe3f748555a57921c","last_reissued_at":"2026-05-18T00:05:10.184242Z","signature_status":"signed_v1","first_computed_at":"2026-05-18T00:05:10.184242Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"1809.08179","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":"2026-05-18T00:05:10Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"5z9oEwj7BBLvs+zGlt69CvQixTvl5I/ntRCu+eEA+UJyeFR+nJCElpqC8xb9LxWmjks4oopV5gk6vRe2L9vNDA==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-05-25T20:23:10.594106Z"},"content_sha256":"abd1d6cd19ba70692a311aefa08c044f10bec39cd6ff673b881f034149f8841f","schema_version":"1.0","event_id":"sha256:abd1d6cd19ba70692a311aefa08c044f10bec39cd6ff673b881f034149f8841f"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2018:S6KKVY2FPLQEILHR6DAYYVGD5Z","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"Optimizing Bone Scaffold Porosity Distributions","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"q-bio.TO","authors_text":"Dvina Valainis, Kaushik Bhattacharya, Martijn van Griensven, Patrick Dondl, Patrina S.P. Poh","submitted_at":"2018-09-21T15:52:47Z","abstract_excerpt":"We consider a simple one-dimensional time-dependent model for bone regeneration in the presence of a bio-resorbable polymer scaffold. Within the framework of the model, we optimize the effective mechanical stiffness of the polymer scaffold together with the regenerated bone matrix. The result of the optimization procedure is a scaffold porosity distribution which maximizes the stiffness of the scaffold-bone system over the regeneration time, such that the propensity for mechanical failure is reduced."},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1809.08179","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":"2026-05-18T00:05:10Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"JJPQIvmmn9CKdO6Hiij8O9peQVFcd2mGoMj02Yu0kFpdH4HnbNFDz72FAbnis7YgSyR2YCxG4X3SjKtxYI5dDQ==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-05-25T20:23:10.594532Z"},"content_sha256":"f026cba9825f81adb4f523fa68bc643c860f9624be163b88206c91031c438106","schema_version":"1.0","event_id":"sha256:f026cba9825f81adb4f523fa68bc643c860f9624be163b88206c91031c438106"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/S6KKVY2FPLQEILHR6DAYYVGD5Z/bundle.json","state_url":"https://pith.science/pith/S6KKVY2FPLQEILHR6DAYYVGD5Z/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/S6KKVY2FPLQEILHR6DAYYVGD5Z/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":"2026-05-25T20:23:10Z","links":{"resolver":"https://pith.science/pith/S6KKVY2FPLQEILHR6DAYYVGD5Z","bundle":"https://pith.science/pith/S6KKVY2FPLQEILHR6DAYYVGD5Z/bundle.json","state":"https://pith.science/pith/S6KKVY2FPLQEILHR6DAYYVGD5Z/state.json","well_known_bundle":"https://pith.science/.well-known/pith/S6KKVY2FPLQEILHR6DAYYVGD5Z/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2018:S6KKVY2FPLQEILHR6DAYYVGD5Z","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":"52a480c6ea22f3174987a563f09b4c40681b16481520b2aa02351aaaac362a93","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"q-bio.TO","submitted_at":"2018-09-21T15:52:47Z","title_canon_sha256":"8588f63d30dc4c0dd2b168c486b9af1132409d17a4e83e97d102c53a2c748391"},"schema_version":"1.0","source":{"id":"1809.08179","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1809.08179","created_at":"2026-05-18T00:05:10Z"},{"alias_kind":"arxiv_version","alias_value":"1809.08179v1","created_at":"2026-05-18T00:05:10Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1809.08179","created_at":"2026-05-18T00:05:10Z"},{"alias_kind":"pith_short_12","alias_value":"S6KKVY2FPLQE","created_at":"2026-05-18T12:32:50Z"},{"alias_kind":"pith_short_16","alias_value":"S6KKVY2FPLQEILHR","created_at":"2026-05-18T12:32:50Z"},{"alias_kind":"pith_short_8","alias_value":"S6KKVY2F","created_at":"2026-05-18T12:32:50Z"}],"graph_snapshots":[{"event_id":"sha256:f026cba9825f81adb4f523fa68bc643c860f9624be163b88206c91031c438106","target":"graph","created_at":"2026-05-18T00:05:10Z","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 consider a simple one-dimensional time-dependent model for bone regeneration in the presence of a bio-resorbable polymer scaffold. Within the framework of the model, we optimize the effective mechanical stiffness of the polymer scaffold together with the regenerated bone matrix. The result of the optimization procedure is a scaffold porosity distribution which maximizes the stiffness of the scaffold-bone system over the regeneration time, such that the propensity for mechanical failure is reduced.","authors_text":"Dvina Valainis, Kaushik Bhattacharya, Martijn van Griensven, Patrick Dondl, Patrina S.P. Poh","cross_cats":[],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"q-bio.TO","submitted_at":"2018-09-21T15:52:47Z","title":"Optimizing Bone Scaffold Porosity Distributions"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1809.08179","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:abd1d6cd19ba70692a311aefa08c044f10bec39cd6ff673b881f034149f8841f","target":"record","created_at":"2026-05-18T00:05:10Z","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":"52a480c6ea22f3174987a563f09b4c40681b16481520b2aa02351aaaac362a93","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"q-bio.TO","submitted_at":"2018-09-21T15:52:47Z","title_canon_sha256":"8588f63d30dc4c0dd2b168c486b9af1132409d17a4e83e97d102c53a2c748391"},"schema_version":"1.0","source":{"id":"1809.08179","kind":"arxiv","version":1}},"canonical_sha256":"9794aae3457ae0442cf1f0c18c54c3ee71154e04a74e89ebe3f748555a57921c","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"9794aae3457ae0442cf1f0c18c54c3ee71154e04a74e89ebe3f748555a57921c","first_computed_at":"2026-05-18T00:05:10.184242Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-18T00:05:10.184242Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"qazZydZTBxMMZV/Q32LqVyPdTsB9yK2ISIKXVnbrcGyXETkyMasQYTDNXmjHT2uw57w5U1tJ2R3QDD09r7P8BA==","signature_status":"signed_v1","signed_at":"2026-05-18T00:05:10.184812Z","signed_message":"canonical_sha256_bytes"},"source_id":"1809.08179","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:abd1d6cd19ba70692a311aefa08c044f10bec39cd6ff673b881f034149f8841f","sha256:f026cba9825f81adb4f523fa68bc643c860f9624be163b88206c91031c438106"],"state_sha256":"5084b73ee5d93a07ca956626a8aaf1374e13dca47559cd5126322844c0d459f4"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"v+iQyDqBmnyTYGE8Se6FxYjWQVSRySXI0IFCNL++8+gamwdRYufXyp/DWNY18GVCY4GcEQcAxEoGg/KesZffAw==","signed_message":"bundle_sha256_bytes","signed_at":"2026-05-25T20:23:10.597568Z","bundle_sha256":"ad5a06125b6be697cd31dbbc834d0e8b0e3b0fb06e6af5c7338bf736bc54d601"}}