The Translational Gap in Low-Energy Radiation Research: Bibliometric Evidence of a Materials-to-Food Knowledge Flow

This dataset contains supplementary materials accompanying the manuscript "The Translational Gap in Low-Energy Radiation Research: Bibliometric Evidence of a Materials-to-Food Knowledge Flow," submitted to Radiation Physics and Chemistry. The dataset includes bibliometric network files, centrality analyses, and visualization outputs from a comprehensive mapping of low-energy radiation research (1990–2024). The analysis employed VOSviewer (version 1.6.20) for keyword co-occurrence and country co-authorship network construction, and UCINET 6 (version 6.528) for quantitative centrality metrics (degree, betweenness, closeness, and eigenvector centrality). Data were retrieved from the Scopus database in June 2026, with the final corpus comprising 2,938 English-language publications. FILE DESCRIPTIONS File Description Format Supplementary File 1.csv Keyword cleaning log containing systematic documentation of all synonym merges and noise term removals. The cleaning procedure consolidated 235 synonym groups, reducing unique keywords from 17,360 to 17,125 (1.4% reduction) and achieving a 23.7% reduction in fragmented co-occurrence links. CSV Supplementary File 2_low_energy_keyword_cooccurrence.png VOSviewer keyword co-occurrence network visualization showing seven distinct research clusters (962 items; 5,231 links; total link strength = 6,444). Node size represents occurrence frequency; edge thickness represents co-occurrence strength; node colors represent distinct research clusters identified by modularity-based clustering (resolution = 1.0; modularity Q = 0.54; silhouette S = 0.73). The emerging food safety and sterilization cluster is highlighted in red. PNG Supplementary File 2_low_energy_countries.png VOSviewer country co-authorship network visualization showing three geographically structured collaboration clusters (86 countries; 5,231 links; total link strength = 6,444). Node size represents total document count; edge thickness represents co-authorship strength. Three major geographic clusters are identified: Western Core (green), Eastern European-Russian axis (orange), and Asia-Pacific (purple/pink). PNG Supplementary File 2_low_energy_overlay.png Temporal overlay visualization showing the evolution of research themes from 1990 to 2024. Node color reflects average publication year (dark blue ~2000 to yellow-green ~2020+). The overlay confirms the food safety cluster as both structurally peripheral and temporally the newest addition to the field. PNG Supplementary File 2_low_energy_bibliographic_coupling.png Bibliographic coupling network visualization identifying research fronts and sub-communities within the field. The network reveals a strongly centralized, single-dominant materials physics cluster with food safety papers appearing as isolated nodes at the periphery, quantitatively reinforcing the translational gap identified in the keyword network. PNG Supplementary File 3_low_energy_centrality_analysis.xlsx UCINET 6 centrality outputs containing full datasets of degree, betweenness, closeness, and eigenvector centrality values for all keywords and countries in the low-energy radiation network. Excel Supplementary File 3_low_energy_countries_centrality.xlsx Country-level centrality metrics for 86 nations in the low-energy radiation co-authorship network, including degree centrality, betweenness centrality, closeness centrality, and eigenvector centrality values. Excel Supplementary File 4_low_energy_keyword_density.png Density visualization of keyword co-occurrence highlighting the peripheral position of the food safety and sterilization cluster. The density map shows areas of high keyword concentration (red/orange) and peripheral areas (blue/green), confirming the structural isolation of the food safety cluster from the physics core. PNG KEY FINDINGS FROM THE ANALYSIS Seven distinct research clusters were identified, dominated by ion beam physics, radiation measurement, and electron beam technology An emerging food safety and sterilization cluster exhibits negligible betweenness centrality (0.000 for keywords "food safety," "food irradiation," and "radiation sterilization"), indicating a structural translational gap between physics and food science communities Eastern European nations show low brokerage scores despite substantial publication output, reflecting a technology transfer gap historically grounded in Soviet-era centralization and post-1991 institutional fragmentation The Asia-Pacific region (China, India) demonstrates high brokerage capacity, contrasting with the Eastern European pattern, and reinforcing that publication output alone does not determine a country's role in knowledge transfer Bibliographic coupling analysis confirms that only 23 out of 2,938 papers (0.8%) contain keywords from both the materials physics domain and the food safety domain—the only genuine bridge documents in the corpus Citation analysis reveals that nine of the ten most cited papers address materials science, with the sole food safety paper ranking 10th with 4.7 times fewer citations than the most cited document METHODOLOGY SUMMARY Search Strategy: Data were retrieved from the Scopus database in June 2026 using a comprehensive search string capturing low-energy radiation research across beam types (electron beams, X-rays, ion beams) and application domains (irradiation, surface treatment, dosimetry, food safety). The corpus comprises 2,938 English-language publications from 1990 to 2024. Keyword Cleaning: Raw keyword fields were processed to address synonym fragmentation, consolidating 235 synonym groups and reducing fragmented co-occurrence links by 23.7%. All cleaning decisions were documented in Supplementary File 1. Network Construction: Keyword co-occurrence and country co-authorship networks were constructed using VOSviewer (version 1.6.20) with full counting method (minimum 1 occurrence for keywords; minimum 3 documents per country). Cluster identification used modularity-based clustering (resolution = 1.0; Q = 0.54; S = 0.73). Sensitivity analyses at resolutions 0.8, 1.0, and 1.2 confirmed cluster stability. Centrality Analysis: Quantitative network centrality metrics (degree, betweenness, closeness, eigenvector) were computed in UCINET 6 (version 6.528). Betweenness centrality served as a proxy for brokerage capacity—the ability to connect otherwise disconnected research communities. LICENSE Creative Commons Attribution 4.0 International (CC BY 4.0) KEYWORDS Low-energy radiation; Bibliometric analysis; Knowledge transfer; Technology transfer; Food safety; Betweenness centrality; Electron beam irradiation; VOSviewer; UCINET; Radiation processing; Bibliometric coupling; Citation analysis FUNDING Dr. Custer C. Deocaris received support under the International Atomic Energy Agency (IAEA) Coordinated Research Project (CRP) D61025: "Innovating Radiation Processing of Food with Low Energy Beams from Machine Sources" and the DOST-PNRI GAA. Dr. Alfredo V. Alcantara Jr. is a Balik Scientist under the Department of Science and Technology – Philippine Council for Industry, Energy and Emerging Technology Research and Development (DOST-PCIEERD).