Advancing Open Science

The El Niño–Southern Oscillation (ENSO) is one of the most important climate phenomena on Earth due to its impacts on the global atmospheric circulation. This paper conducts a comprehensive analysis of the spatiotemporal variations and characteristics of ENSO from 1950 to 2023. A number of indices, including the Oceanic Niño index, Modoki index, and the modified El Niño Modoki Index, were used to differentiate between various ENSO types and assess their respective impacts on the global climate. The analysis reveals notable changes in the frequency and intensity of ENSO events over the past seven decades. Notably, since 1990, the sea surface temperature anomalies (SSTAs) in the tropical Western Pacific regions have shifted westward by approximately 18 degrees longitude, potentially a result of global warming. During the same time period, the frequency and intensity of ENSO events have also changed, with an increase in the frequency of Central Pacific El Niño events and a decline in the frequency of Eastern Pacific El Niño events. The occurrence frequency of both Central and Eastern Pacific La Niña events has remained relatively stable but shows some variability. Based on the analysis results, this article also suggests potential improvement in data collection, which is critical to further understanding and verification of the spatiotemporal variations of ENSO events.

Today, the engineering of load-bearing bone tissue after severe trauma still relies on metal-based (Ti, CoCrMo alloys or stainless steel) permanent implants. Such artificial scaffolds are typically applied in the body and come into direct contact with the recipient’s cells, whose adhesion affects the patient’s implant acceptance or rejection. The present study aims to create a nano-rough texture by means of ultra-short femtosecond laser (fs)-induced periodicity in the form of laser induced periodic surface structures (LIPSS) on the surface of a stainless steel implant model, which is additionally functionalized via magnetron-sputtering with a thin Cu layer, thus providing the as-created implants with a stable antimicrobial interface. Calcium phosphate (CaP) crystal growth was additionally applied due to the strong bioactive interface bond that CaPs provide to the bone connective tissue, as well as for the strong interface bond they create between the artificial implant and the surrounding bone tissue, thereby stabilizing the implanted structure within the body. The bioactive properties in the as-created antimicrobial hybrid topographical design, achieved through femtosecond laser-induced nanoscale surface structuring and micro-sized CaP crystal growth, have the potential for subsequent practical applications in bone tissue engineering.

The increasing trend towards electrification in transportation highlights the potential for electric ships and the demand for safe, rapid charging systems. Underwater capacitive power transfer (UCPT) is considered a suitable solution due to its high power density potential. This article presents research on and optimization of UCPT for shore-to-ship charging in freshwater environments. It proposes a design for an insulation coupler and explores the influence of parasitic capacitance in the environment. This study demonstrates how the ship and shore impact the coupler’s coupling coefficient and mutual capacitance, thereby affecting the power and efficiency. Through theoretical calculations and finite element analysis, a kW-level UCPT coupler is designed. Experimental verification under different cases confirms the efficiency and constant current output characteristics, with superior performance observed when the coupler is positioned further away from the ship or shore. This study showcases the potential of UCPT to provide reliable and efficient power supply for electric ships, while emphasizing the importance of considering environmental factors and parasitic effects in system design and operation. These findings contribute to advancing UCPT technology and offer insights for further optimization to enhance practical applicability.

Digitization and innovation supported by various innovation systems have become key factors in the sustainable development of companies, countries (including UE countries), and the economy as a whole. The primary objective of this study is to explore the interconnections between the perspectives of the Quintuple Helix model and digitalization as a comprehensive innovation system supporting digitalization in EU countries. The study is grounded in the innovation systems theory, specifically employing the Quintuple Helix Model as a comprehensive framework, and addresses the challenge of digital divide across the EU. The research was conducted using K-means cluster analysis to identify homogeneous groups of countries within the EU. Subsequently, correlation analysis was applied to identify statistically significant relationships between the individual variables examined within the Quintuple Helix model and digitization within EU countries. Based on the results, we identified four distinct clusters of EU countries characterized by different degrees of digitization, governance, and intellectual Capital. It was found that countries with the highest level of digitization are also characterized by the highest levels of governance and intellectual Capital. Correlation analysis confirmed a strong interconnection between the examined perspectives of the Quintuple Helix model and their relationship with digitization.

The proactive adoption of Generative Artificial Intelligence (GenAI) by e-commerce platforms to enhance consumer experience is emerging as a predominant trend. This research investigates the influence of AI overview on consumers’ perceived usefulness of the customer reviews section on e-commerce platforms, thereby further expanding the scope of application of the technology acceptance model (TAM). Across three scenario-based experiments (n = 568), we examined the effects of AI overview and their underlying mechanisms. Results consistently confirmed a main effect: the presence of AI overview significantly enhanced perceived usefulness compared to its absence. Study 2 identified perceived diagnosticity as a mediator, while Study 3 revealed that need for cognition (NFC) moderated both the main effect and the mediation process. Specifically, for High-NFC participants, the presence or absence of AI overview made no significant difference, whereas for Low-NFC participants, AI overviews significantly increased perceived usefulness. These findings offer novel insights into the effectiveness of AI overview in shaping the consumer evaluations of online customer reviews. By clarifying the mediating role of perceived diagnosticity and the boundary condition of NFC, this study contributes to a more nuanced understanding of how AI can be strategically integrated into e-commerce platforms to enhance consumer decision-making and guide business development.

The accumulation of metabolites and the antioxidant response in new strains of Bracteacoccus minor MZ–Ch31 and MZ–Ch39 isolated from various biotopes were studied. It was found that the antioxidant response of B. minor MZ–Ch31 and MZ–Ch39 is different. This may be due to the acclimatization of these strains to specific environmental factors of the natural biotope. Strain B. minor MZ–Ch39 had a higher antioxidant activity compared to B. minor MZ–Ch31. The TBA-reactive substance content in B. minor MZ–Ch39 cells was lower than that of MZ–Ch31. The antioxidant response in B. minor MZ–Ch39 was realized by high catalase and glutathione peroxidase activity and accumulation of retinol. In B. minor MZ–Ch31, the antioxidant response was associated with the accumulation of α-tocopherol and carotenoids. The strains did not differ in terms of superoxide dismutase activity. From a biotechnological point of view, B. minor MZ–Ch31 biomass is a valuable resource of lipids rich in omega-3 fatty acids, α-tocopherol, and carotenoids. The B. minor MZ–Ch39 has the potential to generate lipids enriched with essential omega-6 fatty acids.

To mitigate vibration in thin-walled composite combustion liners of aero-engines, this study proposes an optimization strategy for stiffener design to maximize natural frequencies and suppress resonance. The approach enhances structural dynamics by installing transverse and longitudinal stiffeners along the tubular wall, with their dimensions and orientations systematically optimized. Design variables were chosen: combustion liner wall thickness, stiffener thickness, transverse stiffener width/angle, longitudinal stiffener width, and composite lamination layup scheme. The orthogonal experiments were completed and followed by range analysis and variance analysis. The results demonstrated that wall thickness had the most significant impact on the natural frequency, and the 45° lamination scheme showed a superior performance compared to other configurations. Finally, a predictive equation was developed using a multiple linear regression model. The optimized stiffener configuration markedly enhances natural frequencies, mitigating vibration-induced instability. This methodological framework provides a systematic basis for designing optimized stiffener layouts in composite combustion liners for aero-engines.

This study examined the impact of a shift schedule change on firefighter sleep and health outcomes (n = 24). Firefighters from a U.S. department transitioned from a 24 h on, 48 h off (24/48) schedule to a 48 h on, 96 h off (48/96) schedule. Wrist actigraphy and self-reported health outcomes were assessed at three time points: baseline (24/48), 3 months post-transition, and 6 months post-transition. Objective sleep measures included total sleep time (TST), sleep efficiency (SE), sleep onset latency (SOL), and wake after sleep onset (WASO). Self-reported health outcomes included the Insomnia Severity Index (ISI), Beck Depression Inventory–II (BDI-II), Beck Anxiety Inventory (BAI), Multidimensional Assessment of Fatigue (MAF), and the Alcohol Use Disorders Identification Test (AUDIT). Linear mixed-effects models (LMMs) with random intercepts were used to evaluate changes over time, adjusting for age, years of service, and individual night-time call volume. Results showed significant improvements in TST, SE, SOL, and WASO at the 3-month follow-up, which were sustained but did not further increase at 6 months. ISI and BDI-II scores also improved, while BAI, MAF, and AUDIT remained stable. These findings suggest that the 48/96 schedule may provide short-term improvements in sleep and psychological health for firefighters in low call-volume settings. Additional research is needed in higher-volume departments and over longer timeframes.