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Multifunctional nickel (II) phthalocyanines with oxygen-bridged substituents: Synthesis, biological evaluation, and computational studies
No full textIn this study, novel nickel (II) phthalocyanines bearing functional groups with different atoms such as fluorine, sulfur, and oxygen, connected by oxygen bridges at their peripheral positions, were synthesized and characterized. The singlet oxygen generation, antioxidant, antibacterial activities, and cytotoxicity of the phthalocyanines (1a-4a) were systematically evaluated. The synthesized phthalocyanines exhibited solvent-dependent singlet oxygen generation, highlighting their potential as photosensitizers and providing valuable insights into their photochemical properties. Among the molecules, (1a) showed the highest reducing power activity, while (3a) displayed the strongest DPPH radical scavenging activity. Importantly, none of the studied molecules demonstrated toxicity toward HEK-293 cells, and all synthesized molecules showed antibacteriel activity against S. aureus. Furthermore, Gaussian computational studies were performed at the B3LYP, HF, and M062X levels with the 6–31++g(d,p) basis set. Molecular docking analyses were also carried out against zinc superoxide dismutase protein (PDB ID: 1CB4), Human peroxiredoxin 5 protein (PDB ID: 1H2D), and FabH Inhibitors proteins (PDB ID: 4Z8D)
Thermoanalytical and Physical Characterization of Animal Fat and Commercial Organic Phase Change Materials
No full textThe adoption of phase change materials (PCMs) is hindered by the complex characterization of their thermophysical properties, as most studies still address only a narrow range of properties. In this work, temperature-dependent measurements deliver accurate data and enable functional modeling essential for advancing practical applications. Thermophysical characterization of three organic PCMs was conducted, including two commercial paraffins (RT28HC and RT26) and industrially processed pork fat. The comprehensive experimental analysis (temperature-dependent characterization) was provided using differential scanning calorimetry (DSC), the transient hot wire (THW) method, density measurements, and rheological analysis. It was determined that paraffins RT26 and RT28HC have high values of latent heat, amounting to 198.1 kJ kg−1 and 215.8 kJ kg−1 for the endothermic process, respectively. Paraffin RT26 was observed to have two melting peaks, at 19.6 °C and 28.8 °C, while RT28HC showed one at 29.6 °C. The results also revealed that both paraffins in liquid state have almost identical values of thermal conductivity and diffusivity, while in solid state these values differ. Results obtained with DSC and THW deviate significantly from the manufacturer’s datasheet with discrepancies ranging from 10% to 44%. Pork fat showed lower values of latent heat, but slightly higher thermal conductivity and diffusivity. The melting peak of pork fat was measured at 34.8 °C. All three materials were found to behave like Newtonian fluids, with pork fat having the highest viscosity of 73.2 mPas at 20 °C. Specific heat capacity was also calculated for all samples, with the highest value of 2.559 kJ kg−1 K−1 determined for RT28HC at 60 °C. It was also discovered that the THW apparatus is able to detect the onset of liquid-to-solid transition in paraffins and pork fat. The key research outcomes of this work are useful for numerical modeling since reliable dataset of thermophysical properties is provided herein, and which is ultimately needed for accurate numerical modeling of PCM-based thermal energy storage (TES) systems
EXAMINATION OF STUDENT PERCEPTIONS OF ASYNCHRONOUS LEARNING ENVIRONMENTS WITHIN THE FRAMEWORK OF TECHNOLOGY ACCEPTANCE MODEL
No full textAn examination of pre-service teachers’ public speaking attitudes with respect to sportive activity and demographic variables
No full textIntroduction: Public speaking is a core professional skill for teachers, shaping classroom interaction and instructional effectiveness, yet it is frequently accompanied by anxiety and avoidance. This study examined pre-service teachers’ public speaking attitudes in relation to demographic characteristics and participation in sports activities, focusing on enjoyment, perceived importance, and anxiety. Method: A descriptive survey design was used with 464 pre-service teachers (333 female, 131 male) enrolled at the Faculty of Education of Atatürk University during the 2024–2025 academic year. Data were collected using a Personal Information Form and the Public Speaking Attitude Scale (PSAS), adapted into Turkish by Aydoğan and Çelik (2024). All sub-dimensions demonstrated strong reliability (α > 0.80). Independent samples t-tests, one-way ANOVA, and Pearson correlation analyses were conducted. Results: Male participants reported significantly higher enjoyment of public speaking, whereas female participants exhibited higher anxiety levels. Age showed a small but significant positive association with enjoyment. Family structure was significantly related to anxiety, with students from broken families reporting higher anxiety than those from nuclear or extended families. Participation in sports activities was associated with more favorable public speaking attitudes; students who engaged in sports reported greater enjoyment and lower anxiety compared to non-participants. No significant differences were observed for perceived importance. Conclusion: The findings indicate that public speaking attitudes are shaped by the combined influence of demographic and behavioral factors. In particular, sports participation appears to support the emotional dimensions of public speaking by reducing anxiety and enhancing enjoyment. These results highlight the value of integrating sport-based and socio-emotional practices into teacher education programs to strengthen communicative competence among future teachers
Combustion Behaviour of Selected Waste Wood Samples, Springer Nature, Energy Management, Volume 1: Green Transition
No full textIn Türkiye, fossil fuels have a 90% sharein total primary energy consumption, while 80% of fossil fuel consumption ismet through imports. This amount, which is a clear indicator of the externaldependence of Türkiye in terms of energy, can be reduced by utilizing localresources. Therefore, using waste wood material, one of the existing renewableenergy sources, in existing thermochemical systems would reduce the country'senergy dependence on foreign energy, and CO2 emissions, one of themost important greenhouse gases, would be reduced.The current study aims to determine how theorigin of the waste wood comes from different waste streams and how it affectsthe combustion behaviour of the wood. Five different waste wood samples fromfive different sources were analysed using TGA for combustion behaviouranalysis. </p
Synthesis, in vitro evaluation, and molecular modeling of Donepezil-inspired N-benzylpiperidine–phenolic conjugates as dual-action acetylcholinesterase inhibitors with antioxidant properties
No full textAlzheimer's disease (AD) is associated with multiple pathological processes, including cholinergic deficits and oxidative stress, which together motivate the search for multifunctional agents. In this study, we designed and synthesized a series of N–benzylpiperidine–phenolic acid conjugates that combine the AChE-inhibitory pharmacophore of Donepezil with antioxidant scaffolds. Structural characterization was confirmed by NMR and HRMS. The compounds were evaluated through in vitro AChE inhibition and antioxidant assays, complemented by molecular docking studies. Among the series, PD8 displayed the most potent AChE inhibition (IC50 = 2.38 µM), while PDD4 exhibited the strongest antioxidant effect in the DPPH assay (66.8% at 50 µM). MD simulations further demonstrated that PD8 maintained conformational stability in the AChE active site with a stronger hydrogen bonding profile compared to Donepezil, thereby reinforcing the docking results. These results indicate that methoxy substitution patterns, particularly in PD8, play a decisive role in enhancing AChE activity, whereas hydroxyl-rich scaffolds favor antioxidant effects. Collectively, the findings highlight the potential of benzylpiperidine–phenolic hybrids as tractable chemical scaffolds for further optimization. Future studies will focus on expanding their biological evaluation, including BuChE selectivity and cellular assays, to better establish their therapeutic relevance
Energy and thermal environment analysis of physiotherapy centers: A comparative study of static and dynamic treatments under global climate scenarios
No full textThis study examined how metabolic rates, linked to static and dynamic therapies, affect indoor air temperature, predicted mean vote (PMV), energy consumption, and CO2 emissions in physiotherapy centers. Simulations were performed across five climate zones: tropical rainforest (Af), hot desert (BWh), humid subtropical (Cfa), humid continental (Dfb), and tundra (ET). During static therapies, indoor temperatures remained stable between 25 and 30 °C in Af and BWh climates. In Cfa and Dfb climates, temperatures ranged from 25 to 30 °C in summer and 15–25 °C in winter, while ET climates exhibited a year-round range of 13.2–21.4 °C. Higher metabolic rates increased PMV values above + 2.0 in Af and BWh, causing thermal discomfort. In Cfa and Dfb, moderate comfort was achieved at medium metabolic rates, while in ET, acceptable comfort was observed at higher metabolic levels. Cooling-related electricity consumption in Af and BWh ranged from 23 to 31 kWh m−2. In colder climates, heating demands raised energy use and CO2 emissions, with winter gas consumption reaching 45 kWh m−2 and emissions up to 24 kg m−2. The findings revealed that fixed temperature settings overlook individual and climatic differences, lowering energy efficiency. The study underscores the need for personalized heating, ventilation, and air conditioning systems by explicitly considering the internal heat gains generated by static therapy equipment and those arising from dynamic therapy applications, thereby enhancing their relevance to physiotherapy practice
Is there a role of MOG antibodies in idiopathic intracranial hypertension: A comparative analysis with optic neuritis-MOG antibody associated disease
No full textObjective: Idiopathic intracranial hypertension (IIH) is defined by elevated intracranial pressure without identifiable structural, infectious, or neoplastic cause. While the underlying pathophysiology remains unclear, emerging evidence suggests a potential role for autoimmune mechanisms, including antibodies against myelin oligodendrocyte glycoprotein (MOG). This retrospective study aimed to investigate the presence and clinical relevance of MOG-IgG antibodies in patients with IIH. Methods: We included 58 consecutive patients diagnosed according to the current clinical criteria and divided them into three groups: MOG antibody-associated optic neuritis (MOG-ON, n = 19), MOG-positive IIH (MOG+ IIH, n = 10), and MOG-negative IIH (MOG-IIH, n = 29). MOG-IgG levels were measured using a live-cell-based assay. Clinical characteristics, cerebrospinal fluid (CSF) findings, visual assessments, cranial magnetic resonance imaging (MRI) results, and treatment responses were compared. Results: MOG antibodies were detected in 25.6 % of the patients with IIH. MOG+ IIH patients were exclusively female and had higher rates of diplopia and acute symptom onset than MOG- IIH patients. MOG-ON patients had significantly lower CSF opening pressure. Visual acuity, OCT, and VEP abnormalities were more severe in the MOG-ON group, whereas there were no significant differences between MOG+ IIH and MOG- IIH. Some MRI findings related to IIH (e.g., transverse sinus stenosis) were more common in MOG- IIH. Conclusion: MOG-IgG antibodies may be detected in a subset of IIH patients who exhibit distinct clinical features, suggesting a potential inflammatory or autoimmune etiology. Although a direct causal relationship could not be established, these findings support the need for further investigation into the immunological spectrum of IIH