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Evaluation of the gradual release of responsibility framework's effectiveness on oral summarization skills in Turkish middle school classrooms: A mixed methods study
No full textWe aimed to explore the effects of the gradual release of responsibility framework on sixth-grade students’ oral summarization skills in the Turkish language. The current study employed convergent mixed methods research. In the quantitative phase, a pretest-posttest control group quasi-experimental design was used. The sample of the quantitative phase consisted of 41 sixth-grade students in Türkiye. The qualitative phase included observations about the intervention and the students’ diaries in the experimental group (n = 20). The covariance analyses on the posttest scores of the students revealed that summarization attitudes and summarization achievements of the experimental group students varied significantly compared to the control group students. In addition, it was observed that the intervention provided new insights into how students summarized a text. The students’ diaries showed that while they had difficulties with oral summarization during the intervention, they gradually developed an awareness and they liked to summarize
Synthesis and biological evaluation of some pyrimidine derivatives as multifunctional ligands for the treatment of Alzheimer's disease
No full textAlzheimer's disease (AD) is a neurodegenerative disorder and acetylcholinesterase (AChE), butyrylcholinesterase (BuChE), and sphingomyelinase (SMase) enzymes are among its therapeutic targets. In this study, a series of tetrahydropyrimidine and hexahydropyrimidine derivatives were synthesized and evaluated for their inhibition of Bacillus cereus SMase, electric eel AChE (EeAChE), and equine BuChE (eqBuChE) as potential agents against AD. Among the synthesized compounds, 4-oxo-6-(pyridin-2-yl)-2-thioxohexahydropyrimidine-5-carbonitrile (compound 24) was found to be the most active compound against B. cereus SMase, with an IC50 value of 1.61 mu M. In addition, 2-(benzylthio)-4-octyl-6-oxo-1,6-dihydropyrimidine-5-carbonitrile (compound 14) and 4-octyl6-oxo-2-(phenethylthio)-1,6-dihydropyrimidine-5-carbonitrile (compound 16) exhibited selective eqBuChE inhibition with IC50 values of 3.68 and 1.65 mu M, respectively. The mode of inhibition of the selected compounds was determined by enzyme kinetic study. These compounds were also examined for their metal-chelating properties with various biometals and effect of B. cereus-induced hemolysis on sheep erythrocytes. Additionally, compound 24 showed no cytotoxic effect on the HUVEC cell line at its IC50 concentration. The biological data were supported by the results of molecular docking studies, and in-silico physicochemical properties/ADME predictions of the selected compounds were determined
Examining the psychological symptoms of pediatric oncology nurses and barriers to seeking psychological help: A mixed-methods study
No full textInsights Into Intramolecular Charge Transfer in a Benzoxazole-Substituted TAPP Derivative: Solvent Effects and DFT Analysis
No full textIn this study, synthesis, characterization, photophysical properties, and DFT calculations of a new tetraaryl-1,4-dihydropyrrolo[3,2-b]pyrrole (TAPP) derivative molecule of A-π-D-π-A type containing benzoxazole as an acceptor group at 1,4-positions have been carried out. The target A-D-A type molecule was synthesized using 4-(benzo[d]oxazol-2-yl)aniline by the method known in the literature, and it was aimed to obtain the classical TAPP structure in an iron-catalyzed environment. No product was obtained with the first method; therefore, the reaction conditions were optimized. The reaction time and temperature were varied in a controlled manner; the optimum conditions were determined with a reaction time of 7 h at 60°C. The photophysical behavior of the synthesized benzoxazole-substituted TAPP derivative was investigated by UV–vis and fluorescence spectroscopy depending on different solvent polarities. In the absorption spectra, the maximum absorption band observed around 330 nm in low polarity solvents shifted to 340 nm in polar solvents. Similarly, fluorescence emissions systematically red-shifted from hexane to DCM (470–550 nm), and quantum yields decreased significantly (0.41 in hexane and 0.03 in DCM). This bathochromic shift and decrease in intensity indicate that the molecule has high polarity in the excited state whereas the intrinsic charge transfer (ICT) and twisted ICT (TICT) states stabilize with increasing solvent polarity. At the same time, nonluminescent transition channels such as loss of planarity, oxygen-induced quenching, and internal conversion in the solvent-excited state also decrease the fluorescence intensity. The findings reveal that this TAPP derivative forms a strong donor-acceptor system and exhibits high sensitivity to solvent environment
Quality of life, physical activity levels, exercise capacity, and chronotropic incompetence in patients with type 1 diabetes mellitus
No full textPurpose: Hyperglycemia in Type 1 diabetes mellitus (T1DM) leads to endothelial and vascular dysfunction, affecting various bodily functions, including psychological well-being, exercise capacity, and pulmonary function. This study investigates the impact of T1DM on quality of life, physical activity, exercise capacity, chronotropic response, pulmonary function, muscle strength, endurance, fatigue, and dyspnea. Methods: In a cross-sectional study, 27 patients with T1DM and 26 healthy controls were compared. Quality of life World Health Organization (WHO) index, physical activity (metabolic holter), maximal exercise capacity (incremental shuttle walking test (ISWT)), chronotropic incompetence, pulmonary function (spirometer), muscle strength (dynamometer), respiratory muscle strength (mouth pressure device) and endurance (threshold loading test), fatigue (Fatigue Severity scale (FSS)), dyspnea (modified Medical Research Council scale (MMRC)) were evaluated. Results: WHO index, physical activity levels, chronotropic index, pulmonary function, MIP, MEP, respiratory muscle endurance, FSS, and MMRC scores were similar between groups (p > 0.05). ISWT distance was clinically decreased in patients (p > 0.05). Quadriceps femoris muscle strength was reduced in patients (p < 0.05). 76 % of T1DM patients were inactive based on step counts, and 100 % were less active according to MET values. Also, 11.53 % exhibited chronotropic incompetence, 61.53 % reported severe fatigue, and 15.38 % experienced dyspnea. Conclusion: Maximal exercise capacity decreased clinically in patients with T1DM, while respiratory muscle strength, endurance, and quality of life remain preserved. Muscle strength declines, with 28 % showing restrictive pulmonary function abnormalities. Thus, directing T1DM patients to exercise training and providing physical activity counseling are recommended
Synthesis, characterization and antitumor assessments of sulfonamide-1,2,4-triazole compounds with egrf inhibitory potential: dft calculation, molecular docking, molecular dynamics, and MM/PBSA approaches
No full textSulfonamide-containing 1,2,4-triazole compounds (2a–2g) were synthesized and characterized using FTIR and NMR spectroscopy. Theoretical investigations were performed for compounds 2a, 2c, 2f, and 2g using the DFT/B3LYP/6-311++G(d,p) method. The optimized geometries, IR, and NMR data for these compounds were obtained and compared with experimental ones. The results indicate the presence of intermolecular N–H⋯O type hydrogen bonds, as also confirmed by molecular electrostatic potential (MEP) maps. The newly synthesized compounds were evaluated for their anticancer potential against the normal lung cell line [Beas2B (RRID: CVCL-0168)] and several lung cancer cell lines, including [A549 (ATCC: CCL-185), Calu1 (ATCC: HTB-54), H1650 (ATCC: CRL-5883), SCLC21H (RRID: CVCL-0024), and PC9 (RRID: CVCL-B260)]. Notably, compounds 2a and 2d exhibited significant anticancer activity, with Total Growth Inhibition (TGI) values ranging from 69.13 to 93.15 µg/mL against cancer cells, while showing minimal cytotoxicity toward normal cells (TGI: 211.55 and 281.17 µg/mL, respectively). DNA-binding studies revealed that compounds 2a (Kb: 2.8 × 10² M⁻¹) and 2d (Kb: 1.0 × 10³ M⁻¹) exhibited stronger interactions with CT-DNA compared to the others. Importantly, compound 2d showed stable and selective binding at the EGFR active site, as demonstrated by molecular docking, 100 ns molecular dynamics (MD) simulations, and MM/PBSA free energy analysis. These computational findings are consistent with the biological data, suggesting that compound 2d is a promising candidate for EGFR-targeted anticancer therapy
New fluorescent coumarin dyes containing functional acceptor groups: The investigation of photophysical, optical, and thermal properties
No full textNine novel coumarin-based compounds with a donor-π-acceptor system were synthesized, and their structural characterizations were determined by spectroscopic methods. The effects of different acceptor groups, such as dicyanovinyl, cyanoacrylic acid, and rhodanine-3-acetic acid at the 3-position of the coumarin ring, on the electronic and optical properties of the structure were investigated. Moreover, the coumarin structure was derived by adding an electron donor methoxy group, and a fused benzene ring, which also increases the planar structure. Synthesized compounds' absorption and emission properties are strongly influenced by substitution in the coumarin moiety. Four dyes showed near-IR emission in the solid state with green to orange fluorescence under UV light. The structural and electronic properties of the molecules were obtained with the DFT calculations at B3LYP/6-311++g(d,p) level of theory. The frontier molecular orbitals and the global reactivity descriptors were computed. Additionally, some DSSC parameters for 3a-c and 5a-c were also determined to provide insight into their potential. All compounds showed good thermal stability (Td > 200 °C)
Design, synthesis, computational insights, and evaluation of tetrazole containing donepezil derivatives as antibiofilm, antimicrobial, and anticancer agents with doxorubicin
No full textTetrazole is an active functional group commonly used in bioactivity studies. It is found in the structures of commercially available drugs such as losartan, cilostazol, and oteseconazole, and is also frequently involved in anticancer studies. Therefore, tetrazole-containing donepezil derivatives (2a-s) were synthesised and evaluated for antimicrobial, antibiofilm, and anticancer activities. Compounds were tested against Candida albicans (ATCC 10231), Escherichia coli (ATCC 25922), Staphylococcus aureus (ATCC 29213), and the triple-negative breast cancer (TNBC) cell line MDA-MB-231. Notably, several derivatives showed potent inhibition of both Grampositive, Gram-negative bacteria and biofilm formation, as well as C. albicans. In the anticancer assays, compounds were screened via MTT assays, and their cytotoxicity was also assessed in combination with doxorubicin. The MDA-MB-231 cell line was selected due to its aggressive, chemoresistant phenotype representative of TNBC, a subtype with limited treatment options. Some compounds exhibited moderate to strong synergistic effects with doxorubicin, suggesting potential as adjuvant therapy candidates. Molecular docking and 100 ns molecular dynamics simulation analyses of compounds interacting with the enzymes Dihydropteroate Synthase (DHPS) and Sterol 14-alpha Demethylase (CYP51) were performed. Docking results revealed that compounds 2o and 2h exhibited similar or superior interaction profiles with target enzymes compared to natural substrates and reference ligands. These findings support the multifunctional therapeutic potential of tetrazole-containing donepezil derivatives for further preclinical investigation in infectious and oncologic applications
Acute electrical muscle stimulation effects on strength and anaerobic power in soccer players
No full textAnaerobic power and lower limb muscle strength are of great importance in soccer, and various preloading strategies are used to improve these abilities. We investigated the acute effects of electrical muscle stimulation on muscle strength and anaerobic power in soccer players. Nineteen healthy male soccer players (age=21.1±1.6 y, training experience=10.1±3.2 y, height=178.1±4.0 cm, and body mass=8.9±3.7 kg) participated in the study. A placebo effect was created without telling the participants that which current (intensity) was applied. After the current applied to the quadriceps muscles, strength and anaerobic power tests were performed. Perceived exertion assessment was also collected after the performance tests. The 75 Hz current exhibited better performance in dominant (p <0.001 and d =0.75) quadriceps muscle group strength (kg). The 75 Hz current condition peak power had significantly higher values than 15 Hz (p <0.05 and d =0.38) and 104 Hz conditions (p <0.05 and d =0.60). Therefore, the 75 Hz current was the most successful in improving lower extremity strength and anaerobic power performances of soccer players. Future research should examine how to utilize sport-specific abilities related to strength and anaerobic power in soccer players for longer periods at peak