Myroslava Hladchenko

Myroslava Hladchenko

This study examined emerging and established topics in drone research, focusing on citation impact and knowledge flows across China, the United States, the EU, Ukraine, and Russia between 2020 and 2025 using OpenAlex bibliographic data. The findings revealed that drone-related science is characterised by growing geopolitical asymmetries in scientific production, citation concentration, and international knowledge exchange. In particular, China increasingly dominated scientific production, fractional authorship contribution, and domestic citation circulation. In contrast, the United States and EU countries maintained comparatively more internationally distributed citation structures. However, China-affiliated publications became increasingly integrated into global citation networks, particularly through growing citation exchange with the United States and European countries. Notably, the interpretation of authorship and citation patterns was complicated by the high proportion of publications with unidentified affiliations, which reached 50% in 2025 within weak-signal topics. These findings underscore the importance of developing comprehensive national Research Organisation Registries (RORs). Although China demonstrated a citation advantage, this was partly driven by high internal domestic citation concentration rather than exclusively by global integration. Moreover, China still imported proportionally more knowledge from the EU-14 and the United States than it exported, with this asymmetry increasing over time. EU-14 countries maintained the strongest citation impact in weak-signal topics, suggesting a more prominent role in shaping emerging research directions. At the same time, China-affiliated publications cited the United States more frequently than the EU-14 in both strong- and weak-signal topics, with this pattern being particularly pronounced in weak-signal areas.

Myroslava Hladchenko

This study explores the evolution of bilateral and multilateral research collaboration of nine EU-14 member states, both within Europe and globally, across six disciplines, between 2010 and 2024, using OpenAlex data. Results indicate that bilateral collaboration rates remained relatively stable and predominantly concentrated within EU-14 countries, followed by the USA, the UK, and China. Multilateral collaboration rates increased significantly across all disciplines, with the highest increase observed in medicine and the highest overall rates maintained in physics & astronomy. The same trend across disciplines was observed for the Relative Intensity of Collaboration (RIC). This reflects the growing importance of large-scale international research consortia in infrastructure-intensive fields that address global scientific challenges. RIC has increased for both bilateral and multilateral collaboration, with stronger growth in multilateral collaboration. Multilateral RIC fell below the expected level most frequently with South Korea, India, and China. Across both collaboration types, increases in collaboration rates were generally associated with increases in RIC. No substantial changes in collaboration rates or RIC with the UK were observed following Brexit. A decline in multilateral collaboration with Russia in physics and astronomy coincided with its suspension from Horizon Europe in 2022, while the collaboration rate in medicine increased.

Myroslava Hladchenko

This study examines the evolution of bilateral and multilateral scientific collaboration among EU Member States and between the EU and global partners from 2000 to 2024 using data from OpenAlex and Scopus. The results show that OpenAlex, when restricted to cited articles, yields findings broadly comparable to those obtained from Scopus for assessing country-level research collaboration. Relative Intensity of Collaboration (RIC) values are consistently higher for multilateral than for bilateral partnerships. Increased collaboration intensity during the final years of FP7, the intermediate and later stages of Horizon 2020, and the final years of the study period suggests that EU FP may have strengthened collaboration among participating countries. With regard to European integration, multilateral collaboration intensity increased between the EU-14 and EU-13, between these groups and EU candidate countries, and within the EU-13. Despite this growth, structural asymmetries persist. Bilateral collaboration among EU-14 countries is concentrated within the group and with EU-13, Brazil, Norway, Switzerland, and the United Kingdom, whereas EU-13 countries collaborate more intensively within the group, with EU candidate countries and Russia. EU-14 countries maintain stronger multilateral collaboration with high-income countries such as Australia, Canada, and the United States than do EU-13 countries. For both groups, collaboration with China remains the weakest. Although multilateral collaboration intensity with Russia has declined, it remained above the expected level for the EU-14 in 2024 and was 2.5 times higher than expected for the EU-13. This persistence may reflect the continued participation of Russian researchers in multilateral projects despite Russia's suspension from Horizon Europe in 2022.

Myroslava Hladchenko

This study first examines how APC expenditures, authorship patterns, and publishing venues of Ukrainian scholars changed between the pre-war (2020-2021) and wartime (2022-2023) periods. Second, it explores the extent to which APC levels are associated with the field-normalized citation impact (FNCI) of Gold Open Access articles authored by Ukrainian scholars. Statistical analysis revealed a small but significant correlation between APC amounts and citation impact, though the effect size was minimal, suggesting higher APCs did not substantially boost citations. APC waivers offered by major publishers such as Springer and Elsevier since 2022 resulted in only a slight increase in the number of articles authored solely by Ukrainian scholars. Despite these waivers, MDPI and Aluna maintained the largest shares. Between 2020 and 2023, the number of articles authored solely by Ukrainian scholars in foreign journals fell by 25.7 percent, and total APC spending declined by 24.6 percent, from 1.24 million EUR to 0.93 million EUR. Medicine accounted for the largest share of both articles and APC expenditure, with the majority published in Aluna journals.

Myroslava Hladchenko

This study explores the effects of Russia's full-scale invasion of Ukraine on the international collaboration of Ukrainian scholars. First and foremost, Ukrainian scholars deserve respect for continuing to publish despite life-threatening conditions, mental strain, shelling and blackouts. In 2022-2023, universities gained more from international collaboration than the NASU. The percentage of internationally co-authored articles remained unchanged for the NASU, while it increased for universities. In 2023, 40.8% of articles published by the NASU and 32,2% of articles published by universities were internationally co-authored. However, these figures are still much lower than in developed countries (60-70%). The citation impact of internationally co-authored articles remained statistically unchanged for the NASU but increased for universities. The highest share of internationally co-authored articles published by the NASU in both periods was in the physical sciences and engineering. However, the citation impact of these articles declined in 2022-2023, nearly erasing their previous citation advantage over university publications. Universities consistently outperformed the NASU in the citation impact of internationally co-authored articles in biomedical and health sciences across both periods. International collaboration can help Ukrainian scholars to go through this difficult time. In turn, they can contribute to the strengthening of Europe.