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Fluorescence enhancement and quenching study: Interaction of diosgenin with biologically significant macromolecules
No full textDiosgenin, a naturally occurring steroidal sapogenin, has drawn increasing attention due to its broad pharmacological potential. In this study, we investigated its binding interactions with three biologically significant macromolecules: calf thymus DNA (CT-DNA), human serum albumin (HSA), and trypsin. The effects of the diosgenin on the structure and activity of these macromolecules were carried out using fluorescence spectroscopy (type of quenching, binding constant, number of binding locations, thermodynamic parameters, synchronous fluorescence, FRET analysis, 2D, and 3D fluorescence analysis, effect of metal ions), FTIR and molecular docking techniques. The results show that the diosgenin could bind to CT-DNA via a minor groove mode. The fluorescence experiments indicated that the diosgenin binding causes enhancement of HSA fluorescence while the diosgenin binding causes quenching of trypsin fluorescence. Experimental binding studies were conducted to assess the diosgenin's interaction profile, complemented by molecular docking simulations to provide structural insight into the binding modes. Docking results indicated that the diosgenin forms stable complexes with all three targets, exhibiting the highest affinity toward HSA (–10.5 kcal/mol), followed by DNA (–9.0 kcal/mol) and trypsin (–8.1 kcal/mol). The diosgenin was found to bind along the minor groove of DNA, interact with subdomain IB of HSA, and settle within the catalytic pocket of trypsin. In silico analyses indicated high oral absorption, good permeability, and no major toxicity risks, supporting the diosgenin's drug-likeness and multi-target potential. The antioxidant effectiveness of the diosgenin was measured via the DPPH method and reported in terms of its EC₅₀ value
Design of novel exponential pdn controller via quadratic interpolation optimiser for nonlinear and unstable ball and beam system
No full textThis study presents a novel exponential proportional-derivative controller with filter (exp-PDN) for stabilising the nonlinear and underactuated ball and beam system. Unlike conventional PID-based approaches, the proposed controller removes the integral term, resulting in faster transient responses and improved robustness. It incorporates nonlinear exponential shaping of both the error and its derivative, along with a filtered derivative path for enhanced noise handling. A custom multi-objective cost function, comprising the squared error, settling time, and percent overshoot, is proposed to evaluate control performance. The quadratic interpolation optimiser (QIO), a recently developed metaheuristic based on analytical interpolation, is employed to optimise the controller parameters. To validate its effectiveness, the exp-PDN controller is compared against five state-of-the-art metaheuristic algorithms: QIO, spider wasp optimiser, komodo mlipir algorithm, golden eagle optimiser, and slime mould algorithm. The QIO-optimised exp-PDN achieves the best performance, with the lowest cost value (0.3211), minimal overshoot (5.52%), fast rise time (0.97 s), and smallest steady-state error (4.1643 x 10- 4). Further comparisons with QIO-optimised phase-lead and PID-with-filter controllers demonstrate the superiority of the proposed method in both transient and steady-state behaviour. In summary, this work advances the control of nonlinear unstable systems by delivering a structurally simple yet highly responsive control architecture. The combination of dual-channel exponential shaping and efficient metaheuristic optimisation results in state-of-the-art closed-loop performance, highlighting the practical value of the proposed exp-PDN framework for real-world control applications
The influence of social, human and psychological capital on career success: A study in the Turkish banking sector
No full textThe researchers in this study wanted to know whether an individual's social, human and psychological capital had an impact on their career success, and if so, which types of capital had a greater impact on an individual's career success. It also examined whether or not social capital has a mediating effect on the relationship between an individual's human capital and career success. In this context, the data of 400 middle and senior managers working in banks in Turkey were analysed. The results showed that social and psychological capital had a statistically significant, direct and positive influence on their career success, while this was not the case for the relationship between employees' human capital and career success. In addition, the results also showed that social capital has a full mediating effect on the relationship between individuals' human capital and career success
From soil to sustainability: The role of agricultural r&d in decarbonization
No full textThis study explores the largely overlooked impact of agricultural R&D investments on long-term CO2 emissions. By mapping emissions by country and year, it examines their relationship with agricultural R&D alongside economic and environmental factors. Utilizing the Dynamic System GMM approach alongside several benchmark fixed-effects and random-effects regression models, all requisite panel data diagnostic tests were conducted to ensure the robustness of the empirical results. Findings reveal that increased investment in agricultural R&D significantly reduces emissions, highlighting agriculture's untapped potential in climate change mitigation. The study underscores the crucial role of artificial intelligence, digital transformation, green mechanization, and automation in accelerating emission reduction. More than just statistics, these insights serve as a call to action for policymakers, providing concrete evidence that agriculture is a key player in global decarbonization efforts
Kodály yaklaşımı bağlamında Türkiye’de 9. sınıf müzik repertuvarının değerlendirilmesi
No full textAbstract: While the Kodály approach is widely applied in early childhood and elementary music education, it also offers a structured framework suitable for learners at all levels, including secondary education. However, implementing this approach in high schools is complicated by challenges such as students’ limited musical background and inadequate singing experience, thereby requiring the selection of developmentally appropriate and pedagogically meaningful repertoire. In this study, we examined the song repertoire in Türkiye’s 9th Grade Music Teacher’s Guidebook from the perspective of the Kodály approach. Designed as a descriptive research study, the analysis focused on all 53 songs in the guidebook, which were evaluated by 12 expert music teachers based on seven pedagogical categories defining an ideal repertoire for older learners. The results indicated representation across all categories, with folk songs and multi-part works being most frequent, while game songs were found to be the least represented. Variations in teacher evaluations revealed inconsistencies in interpreting categories. Overall, the findings suggest the need to further adapt Kodály-based practices for secondary education.Öz: Çoğunlukla erken çocukluk ve ilkokul müzik eğitiminde uygulanan Kodály yaklaşımı, ortaöğretim dâhil her yaş düzeyi için uyarlanabilir bir çerçeve sunmaktadır. Ancak lise düzeyinde uygulamada, öğrencilerin sınırlı müziksel geçmişleri ve yetersiz şarkı söyleme deneyimleri gibi güçlükler ortaya çıkmaktadır. Bu durum, gelişimsel olarak uygun ve pedagojik açıdan anlamlı bir repertuvar seçimini kritik hâle getirmektedir. Bu araştırma, Türkiye’de 9. sınıf Müzik Dersi Öğretmen Kılavuz Kitabı’nda yer alan şarkı repertuvarını Kodály yaklaşımı çerçevesinde incelemiştir. Betimsel olarak tasarlanan çalışmada, kitaptaki 53 şarkı, daha büyük yaş grupları için ideal bir repertuvarı tanımlayan yedi kategori temelinde 12 uzman müzik öğretmeni tarafından değerlendirilmiştir. Bulgular tüm kategorilerin temsil edildiğini; türkülerin ve çok bölümlü eserlerin en yoğun, oyun şarkılarının ise en az yer alan türler olduğunu göstermektedir. Öğretmen değerlendirmeleri arasındaki farklılıklar kategori yorumlarında tutarsızlıklara işaret etmektedir. Sonuçlar, Kodály temelli uygulamaların ortaöğretim öğrencileri için daha fazla uyarlamaya ihtiyaç duyduğunu göstermektedir
Synergistic adsorption and photocatalysis effect of boron-grafted sba-15-mesotio2 for doxorubicin photodegradation
No full textAdsorptive removal and photocatalytic degradation of organic pollutants in wastewater is an important process in terms of energy and cost in water decontamination. This study focused on the development of a nanocomposite in which both mesoporous TiO2 and boron were integrated into SBA-15 matrix for the production of photocatalyst with effective adsorptive and photocatalytic potential. SBA-15-mesoTiO2-B(X) nanocomposites were prepared by grafting boron at different molar ratios onto the SBA-15-mesoTiO2 prepared by sol-gel synthesis and tested in the adsorption followed by photocatalysis of Doxorubicin (DOX) anticancer agent. FT-IR analysis indicated that Ti-O-Si and Ti-O-B bonds were formed for boron-grafted photocatalysts. XRD analysis disclosed that substitutional Ti was placed in the amorphous channels of SBA-15, and N2-adsorption/desorption analysis revealed an increase in surface area up to 1001.2 m2/g. The highest photoactivity was obtained with SBA-15-mesoTiO2-B(0.5) nanocomposite toward DOX (91% discoloration efficiency). Moreover, almost complete degradation of DOX was achieved, which is the ultimate goal for water pollution removal. XPS and UV/Vis analyses have proven that substitutional and interstitial incorporation of boron causes the formation of surface defects and also increase photoactivity with the presence of different Ti environments. From the scavenge test, it was concluded that the major reactive species responsible for DOX degradation were center dot OH radicals, and no significant degradation was caused by center dot O2 - radicals. Furthermore, the success of the prepared photocatalyst in reuse with only 22% loss was also considerably high. This study provides insights into the potential application of SBA-15-mesoTiO2-B(X) nanocomposites for combined adsorption/photocatalysis wastewater treatment process
Retroperitoneal sentinel lymph node biopsy using vnotes in endometrial cancer patients with a bmi ≥ 30 kg/m 2 : A pilot multicenter case series by the turkish gynecologic oncology group (trsgo-sln12)
No full textAimThis study evaluated the feasibility and surgical outcomes of transvaginal natural orifice transluminal endoscopic surgery (vNOTES) for retroperitoneal sentinel lymph node biopsy (SLNB), specifically targeting obese and morbidly obese patients diagnosed with endometrial cancer (EC).MethodsPathohistological evaluation confirmed the diagnosis of either Grade I or II endometrioid EC in all participants.ResultsIn total, 31 patients participated in this study. The median age was 56 [43-75] years and the median BMI was 34 [30-54] kg/m2. Near-infrared fluorescence imaging utilizing ICG was implemented in 17 cases (54.8%), while methylene blue dye was used in 14 cases (45.2%). A median, 4 sentinel lymph nodes (SLNs) were excised per patient, with numbers ranging from 1 to 7. The overall SLN detection rate was 90.3%, with unilateral detection in 9.7% of patients and bilateral detection in 80.6%. During the surgery, two complications occurred, and an additional two developed afterward. In 3.2% of cases, it was required to switch to a conventional laparoscopic procedure. Lymphatic metastases were identified in 3 patients (9.7%). The median hospital stay was 2 days.ConclusionvNOTES can be a viable alternative to retroperitoneal SLNB, providing distinct benefits, especially for obese and morbidly obese patients with EC
Association between mediterranean diet adherence and intuitive and mindful eating in Turkish young adults
No full textBackground/Objectives: This study aimed to examine the association between Mediterranean diet adherence and adaptive eating behaviors, specifically intuitive eating and mindful eating, among Turkish young adults. Methods: This cross-sectional study included 2293 young adults aged 18-34 years who completed an online survey between December 2023 and March 2024. Data were collected using the Mediterranean Diet Adherence Scale (MEDAS), Intuitive Eating Scale-2 (IES-2), and Mindful Eating Questionnaire (MEQ-30). One-way ANOVA compared eating behavior scores across adherence groups. Hierarchical multiple regression analyses examined the unique contribution of MEDAS scores after controlling for demographic, socioeconomic, health, lifestyle, and nutritional factors. Results: Among the participants, 64.5% demonstrated low, 27.0% moderate, and 8.4% high Mediterranean diet adherence. ANOVA revealed significant differences in both IES-2 and MEQ-30 scores across groups. In hierarchical regression, MEDAS significantly predicted intuitive eating (B = 0.023, p = 0.004, contributing 10.72% to explained variance) and mindful eating (B = 0.776, p = 0.001, contributing 13.61%) after controlling for all covariates. BMI emerged as the strongest predictor for both outcomes, with divergent associations: negative for intuitive eating and positive for mindful eating. Final models explained 5.8% and 6.2% of variance in IES-2 and MEQ-30, respectively. Conclusions: Mediterranean diet adherence demonstrated significant positive associations with both intuitive and mindful eating behaviors, independent of multiple confounders. Although effect sizes were modest, these findings suggest that promoting Mediterranean dietary patterns may complement interventions aimed at fostering adaptive eating behaviors. The divergent BMI associations warrant further investigation.Acibadem Mehmet Ali Aydinlar Universit
Evaluation of uniform diffraction behavior from circular apertures on opaque and perfectly conductive surfaces using bdw theories
No full textPurposeThis study presents a unified and comparative analysis of uniform diffraction fields generated by circular apertures on three canonical surface types: opaque, perfectly electric conductive (PEC) and perfectly magnetic conductive (PMC). This study aims to explore how these boundaries influence field uniformity and angular behavior under identical conditions.Design/methodology/approachThe classical boundary diffraction wave (BDW) theory is applied to the opaque case, and an extended BDW formulation is developed for PEC and PMC surfaces to account for reflective effects. Analytical expressions are derived, and numerical simulations are conducted to examine the impact of aperture size and observation distance.FindingsThe results reveal that PEC and PMC surfaces introduce significant modifications to the angular distribution of the diffracted field, including phase reversals and amplitude oscillations. The extended BDW model successfully predicts these behaviors, particularly near shadow boundaries and axial zones.Research limitations/implicationsThe study is limited to idealized geometries and monochromatic wave excitation. It does not yet consider material losses or complex aperture shapes. Future work may expand this framework to more realistic electromagnetic structures.Practical implicationsThe findings can help electromagnetic engineers optimize antenna design, stealth surfaces and metastructures by offering better control over field uniformity and diffraction behavior across different surface types.Social implicationsWhile the work is theoretical, it supports technological development in sectors like communication, defense and sensing, contributing indirectly to infrastructure reliability and performance.Originality/valueTo the best of the authors' knowledge, this is the first unified parametric study that simultaneously evaluates opaque, PEC and PMC surfaces using classical and extended BDW approaches. It introduces a novel high-frequency framework for comparing uniform diffraction field behavior across distinct boundary conditions
Between ideal and reality: A cross-sectional study of nurses' professional values and barriers to professionalism in Türkiye
No full textEvaluating nurses' professionalism and the obstacles they face is crucial for enhancing healthcare quality and professional satisfaction. The identified challenges still appear to be similar on a global scale. The present cross-sectional study investigated nurses' challenges in meeting professional standards in tertiary healthcare and explored the link between nurses' values and the underlying reasons for these challenges. Data were collected from 500 nurses at a state university hospital using three tools: "Nurse Introduction Form" for sociodemographic and work-related information, "Professionalism Form" to assess understanding of professionalism criteria and barriers, and "Nurses' Professional Values Scale." Results show a positive relationship between the attainability of professional standards and values. The most significant obstacle hindering the achievement of professional standards is systemic. Nurses lack awareness of professional values and are dissatisfied with their profession, especially due to negative working conditions and low income. Due to a lack of authorization, nurses are often unable to provide services fully in line with professional standards. Additionally, this lack of authorization can lead to deviations from their defined job responsibilities. Nurses have limited autonomy and decision-making power despite prioritizing values like human dignity. Meeting professional standards is linked to strongly holding professional values. The relationships between negative factors and NPVS scores show how these issues shape nurses' perception of professionalism