Restore full 19-col schema from 06b06f3

Commit 89b6184 (added 5952 2025- papers) collapsed the schema 19->9 cols,
dropping openAccessPdf(license/disclaimer), fieldsOfStudy, s2FieldsOfStudy,
authors, references, publicationVenue, publicationTypes, lang, lang_conf,
total_tokens, and stringified year/publicationDate/isOpenAccess for all
43,392 rows. The 5,952 added papers were abstract-stubs (median 264 vs 14,003
tokens) and mostly non-OA. This restores 06b06f3: 37,440 full-text papers,
19 columns, licenses intact. History preserved (89b6184 remains in the log).

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

README.md

@@ -9,30 +9,86 @@ size_categories:
 pretty_name: Distributed Ledger Technology (DLT) Scientific Literature
 dataset_info:
   features:
-  - name: paperId
+  - name: lang
     dtype: string
-  - name: text
+  - name: s2FieldsOfStudy
+    list:
+    - name: category
+      dtype: string
+    - name: source
+      dtype: string
+  - name: url
     dtype: string
+  - name: fieldsOfStudy
+    sequence: string
+  - name: lang_conf
+    dtype: float64
   - name: title
     dtype: string
-  - name: abstract
-    dtype: string
-  - name: year
+  - name: paperId
     dtype: string
-  - name: publicationDate
+  - name: venue
     dtype: string
-  - name: url
+  - name: authors
+    list:
+    - name: authorId
+      dtype: string
+    - name: name
+      dtype: string
+  - name: publicationVenue
+    struct:
+    - name: alternate_issns
+      sequence: string
+    - name: alternate_names
+      sequence: string
+    - name: alternate_urls
+      sequence: string
+    - name: id
+      dtype: string
+    - name: issn
+      dtype: string
+    - name: name
+      dtype: string
+    - name: type
+      dtype: string
+    - name: url
+      dtype: string
+  - name: abstract
     dtype: string
-  - name: venue
+  - name: text
     dtype: string
+  - name: openAccessPdf
+    struct:
+    - name: disclaimer
+      dtype: string
+    - name: license
+      dtype: string
+    - name: status
+      dtype: string
+    - name: url
+      dtype: string
+  - name: year
+    dtype: int64
+  - name: publicationTypes
+    sequence: string
   - name: isOpenAccess
-    dtype: string
+    dtype: bool
+  - name: publicationDate
+    dtype: timestamp[us]
+  - name: references
+    list:
+    - name: paperId
+      dtype: string
+    - name: title
+      dtype: string
+  - name: total_tokens
+    dtype: int64
   splits:
   - name: train
-    num_bytes: 2216339218
-    num_examples: 43392
-  download_size: 1167259290
-  dataset_size: 2216339218
+    num_bytes: 2352430295.715864
+    num_examples: 37440
+  download_size: 1245157122
+  dataset_size: 2352430295.715864
 configs:
 - config_name: default
   data_files:

data/train-00000-of-00005.parquet

@@ -1,3 +1,3 @@
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-size 267964909
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+size 248651809

data/train-00001-of-00005.parquet

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+size 250362153

data/train-00002-of-00005.parquet

@@ -1,3 +1,3 @@
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-size 269252555
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+size 248613987

data/train-00003-of-00005.parquet

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-size 267509065
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+size 248475802

data/train-00004-of-00005.parquet

@@ -1,3 +1,3 @@
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-size 93618027
+oid sha256:c47b39f5344042f0fcc537259b8608278099d7f8b5650056bc3ae050066ada08
+size 249053371