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Long-term assessment of forcing conditions affecting the hydrodynamic structure of a stratified sea strait
No full textSea straits are waterways characterized by stratified flow, in which the upper layer flow is driven by barotropic forcing while the lower layer flow is driven by the density difference between adjacent basins. The flow structures of a strait and the water bodies they are connected to are highly dependent on meteorological and hydrological conditions and change significantly as a result of extreme events in these conditions. The present study examines long-term variability in extreme meteorological and hydrological forcing conditions that control the hydrodynamic behavior of a sea strait, the Bosphorus, using 80-year (1931–2010) discharge data of the Danube River and 42-year (1979–2020) meteorological data. In addition to long-term trend analysis, extreme value analysis (EVA) was applied to both the maximum and minimum values of both parameters. In the Danube River discharges, trend directions have changed in successive 20-year periods from 1931 to 2010, but most of the trends are not significant except for the last 20 years of records. Extreme value analysis results indicate that both extreme maximum and minimum discharges are about 10 % greater in recent years (1971–2010) compared with earlier years (1931–1970). The wind conditions in the strait are less variable compared with freshwater discharges. However, the storm analysis indicates the occurrence of more energetic and short-lived storms in the Bosphorus in recent years with greater variability. The variation in extreme pressure differences is more notable, especially in the recent 20-year period. A 37 % decrease in minimum pressure difference, which means higher pressures at the southern entrance of the Bosphorus, indicates that extreme northward current events in the Bosphorus have decreased in recent years. This, combined with the increasing extreme river discharges, indicates a higher dominance of the brackish Black Sea water both in the hydrodynamics of the strait and the Sea of Marmara-northern Aegean Sea system in the future
Production of Polyvinyl Alcohol/Amoxicillin – Chitosan/Collagen Hybrid Bilayer Membranes for Regeneration of Gingival Tissues
No full textPeriodontal diseases, if untreated, can cause gum recession and tooth root exposure, resulting in infection and irreversible damage. Traditional treatments using autologous grafts are painful and often result in postoperative complications. Scaffolds offer a less invasive alternative, promoting cell proliferation and healing without additional surgery, thus enhancing comfort for patients and doctors. This study developed Chitosan (Chit)/Collagen (Col) film surfaces and drug-loaded Polyvinyl Alcohol (PVA)/Amoxicillin (AMX) nanofibers using solvent casting and electrospinning methods, respectively. The surfaces are characterized by scanning electron microscopy (SEM), mechanical testing, Fourier Transform Infrared Spectroscopy (FTIR), and differential scanning calorimetry (DSC). Biocompatibility and antimicrobial properties are assessed using NIH/3T3 fibroblast cells and bacterial cultures. SEM images confirmed the structural integrity of AMX-loaded 13% PVA nanofibers, while FTIR analysis validated the compositional integrity of PVA/AMX nanofibers and Chit/Col film hybrid surfaces. Cell studies showed over 90% viability for Chit/Col film + PVA/AMX nanofiber hybrid bilayer membranes, confirming their biocompatibility. The antimicrobial assessment indicated that the Chit/Col film + PVA/AMX (0.2%) nanofiber hybrid bilayer membrane exhibited superior efficacy against Streptococcus mutans. These findings suggest that this hybrid bilayer membrane can enhance cell growth, promote proliferation, and enable controlled drug release, offering significant promise for regeneration of gingival tissues
Complex Diophantine interval-valued Pythagorean normal set for decision-making processes
No full textInfluence of Infrared Radiation of Drying Characteristics, Total Phenolic Content, Antioxidant Capacity and Color Properties of Pomegranate Seeds
No full textThe aim of this research is to analyze the drying behavior, antioxidant properties, total phenolic content (TPC), and color alterations of pomegranate seeds subjected to infrared drying at temperatures ranging from 55 °C to 75 °C. Analysis of the data revealed a decliningrate drying phase without evidence of a constant-rate phase. The drying rate and duration were found to be directly proportional to the infrared temperature applied; higher temperatures led to faster drying and reduced drying times. The drying process of pomegranate seeds in thin layers was investigated using twelve mathematical models. Among these models, the one presented by Aghbashlo et al. was determined to provide the most precise representation of the drying kinetics. The effective moisture diffusivity values varied between 8.76 × 10−10 and 1.96 × 10−9 m2/s, depending on the temperature range under consideration. Additionally, the activation energy was computed to be 59.37 kJ/mol. The range of TPC values in dry samples fluctuated from 6.19 to 8.20 mg gallic acid equivalent (GAE)/g of dry matter. The 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2,2′-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) and copper-reducing antioxidant capacity (CUPRAC) values varied between 5.57–6.13, 24.18–28.18, 10.33–17.59 TE/g dry matter, respectively. The range of ΔE values for the total color change fell between 3.96 and 9.19. Bioactive compound degradation in samples dried at high drying temperature (75 °C) is higher than in samples dried at 55 and 65 °C. When all the results were evaluated, it was determined that 55 °C was suitable for infrared drying of pomegranate seeds
Uncovering the Links Between Problematic Smartphone Usage and Subjective Vitality: The Role of Mindful Parenting and Parenting Stress
No full textIn recent years, scientific research has increasingly focused on the relationship between parents’ mobile phone usage and parenting. As smartphones have become pervasive among parents, concerns have arisen regarding how this usage might influence parenting practices and well-being. Therefore, studies that examine the relationship between parents’ technology usage—particularly smartphone usage—and their well-being and parenting practices are of significant value. Such research can provide deeper insights into how technology shapes family dynamics and parental roles over time. Our research aimed to investigate the relationships among problematic smartphone usage, mindful parenting, parenting stress, and subjective vitality. The study involved a cross-lagged panel design with two waves of longitudinal research, and parents with at least one child between the ages of 1 and 14 participated. The results revealed that problematic smartphone use has a negative correlation with mindful parenting and subjective vitality, while it has a positive correlation with parenting stress. Serial mediation analysis showed that mindful parenting and parenting stress, both longitudinally and sequentially, mediate the relationship between problematic smartphone usage and subjective vitality. These findings suggest that problematic smartphone use adversely affects parents’ well-being by increasing stress and reducing mindful engagement in parenting. Interventions focusing on reducing problematic smartphone use and enhancing mindful parenting practices may improve parental well-being and reduce stress
Finding new similarities measures for Type-II Diophantine neutrosophic interval valued soft sets and its basic operations
No full textThe Type-II Diophantine neutrosophic interval valued soft set (Type-II DioNSIVSS) and related similarity measure are presented in this study. An extension of the neutrosophic interval valued soft set (NSIVSS) and the Diophantine fuzzy soft set is the Type-II DioNSIVSS. The suggested measure for Type-II DioNSIVSS assessment. We support a method of solving the problem using the Type-II soft set model. To demonstrate how they can be applied to successfully handle uncertainty-related challenges, illustrative examples are given
