Ho Chi Minh City Open University Journal of Science
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The infinite sum of reciprocal Fibonacci numbers
No full textIn this paper, we consider infinite sums from the reciprocals of the Fibonacci numbers. Then applying thefloor function to the reciprocals of this sums, we obtain a new identity involving the Fibonacci numbers.</p
LEFuse: Joint low-light enhancement and image fusion for nighttime infrared and visible images
No full textIn this study, three strains of Enterococcus spp. (E. durans 19, E. durans 77, and E. faecalis 52), isolated from raw milk and confirmed to lack virulence genes (asa1, gelE, cylA, esp, and hyl), were investigated. The biological activities of these strains, including EPS production, antimicrobial and antioxidant properties, auto-aggregation, co-aggregation, hydrophobicity, anti-biofilm activity, acid and bile tolerance, and cholesterol assimilation, were evaluated. Strains showed high exopolysaccharide production, and the highest EPS production was observed in E. durans 19 (440 mg/L). The maximum microbial inhibition zone of 4.50 mm was detected with E. durans 77 against S. aureus ATCC 25923. The antioxidant activity of strains was evaluated by three methods (2.2-Diphenyl1-picrylhydrazil (DPPH), superoxide anion, and hydroxyl radical scavenging activity. E. durans 77 exhibited the highest antioxidant activity of 41.65%, as determined by the DPPH method. Strains exhibited close autoaggregation ability (58%, 56%, and 55%) of each other. E. durans 19 exhibited the strongest coaggregation capacity (65%) against P. aeruginosa ATCC 27853. Three different solvents (chloroform, ethyl acetate, and xylene) were used to designate the hydrophobicity activities of the strains. E. durans 19 and E. faecalis 52 strains exhibited the highest hydrophobicity in ethyl acetate at 83% and 85%, respectively, whereas E. durans 77 demonstrated in chloroform solvent (77%). Antibiofilm activities of three strains against S. aureus ATCC 43300 were examined and values were detected as 29.41-34.17%. In this study, the survivability of the strains to low pH (2.0, 3.0, 4.0, and 6.2) and various bile concentrations (0, 0.06, 0.15, and 0.30) conditions were investigated, and it was observed that the bacterial viability decreased as the acidity and bile concentration in the medium increased. Cholesterol removal capability was determined to a range of 29-40% and cholesterol precipitation between 22.5 and 28.4 mu g/mL
İnsansız Hava Araçlarının Antik Kent Kazı ve Araştırmalarında Kullanımı (İssos Epiphaneia-Erzin)
No full textYAŞ KEDİ MAMALARINDA BİSFENOL A, BİSFENOL B, BİSFENOL E VE BİSFENOL F DÜZEYLERİNİN ARAŞTIRILMASI VE RİSK DEĞERLENDİRMESİ
No full textBiofuel research and development technologies: a Load Capacity Curve analysis for European sustainable development
No full textIn the face of accelerating climate change and resource depletion, the sustainability of biofuels has become an important research focus in environmental economics. While previous studies have extensively examined the role of biofuel consumption in reducing CO2 emissions, the environmental effectiveness of biofuel-specific investments in research and development (R&D) remains largely unexplored. This study fills this gap by empirically assessing the impact of biofuel-related R&D expenditures on the Load Capacity Factor (LCF). Using annual panel data for ten European countries over the period 2009-2023, the analysis rigorously tests the Load Capacity Curve (LCC) hypothesis, which postulates a non-linear, U-shaped relationship between economic growth and ecological balance. The study makes a novel theoretical contribution by integrating biofuel innovations into the LCC framework. Three second-generation panel estimators are used to ensure robust conclusions in the presence of cross-sectional dependence (CSD). The results consistently confirm the LCC hypothesis and reveal that biofuel R&D expenditures have a positive effect on LCF improvement. Furthermore, the estimated turning points indicate heterogeneous ecological transitions across countries, emphasizing the role of income levels and technological capacity in shaping sustainability pathways. By linking the biofuel innovation literature to the LCC framework, this study provides new insights for policymakers seeking to align renewable energy development and technological innovation with the Sustainable Development Goal 7 (SDG-7) targets. The findings highlight the necessity of targeted biofuel R&D strategies to enhance biocapacity, reduce ecological pressure, and guide European economies towards a more resilient and sustainable future
