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From chalk to code: asymmetric nexus between artificial intelligence and educational expenditures
No full textThe rapid advancement of artificial intelligence has prompted significant changes in various sectors, including education. This transformation has led to evolving educational investment as institutions increasingly integrate artificial intelligence (AI) technologies into their teaching and administrative processes. This study examines the asymmetric impact of artificial intelligence on educational expenditures across ten selected nations with advanced AI implementation (USA, China, South Korea, Japan, Germany, UK, Canada, Israel, Singapore, and Sweden). Employing the Quantile-on-Quantile method, the analysis surpasses traditional techniques that may ignore country-specific nuances in panel data research. This approach enables the examination of relationships between variables for each nation individually, thereby improving the accuracy of the findings and providing a valuable understanding of each country’s distinctive characteristics. The results demonstrate that artificial intelligence plays a pivotal role in boosting educational expenditures across most examined countries, each exhibiting distinct trends. These findings underscore the urgent need for policymakers to conduct comprehensive evaluations and develop targeted strategies to navigate the complex relationship between AI and educational investment. By doing so, they can make evidence-based, strategically tailored decisions that address the unique needs of each country
Enhanced triboelectric nanogenerator performance using torrefied biowaste dielectrics
No full textTriboelectric nanogenerators (TENGs) emerge as efficient energy-harvesting devices that convert mechanical energy into electricity. While various dielectric materials have been explored, the potential of torrefied biowaste materials as dielectric layers remains underexplored. This study investigates the triboelectric performance of three unique biowaste materials—torrefied pine sawdust (P.S.), chicken manure (C.M.), and rose pulp (R.P.)—embedded in silicone matrices at varying weight fractions (2.5–10%). The study employs comprehensive material characterization techniques, including scanning electron microscope imaging and electrical performance analysis, to evaluate charge accumulation, dielectric properties, and power generation efficiency. The results reveal that the optimal embedding ratio is 7.5 wt% for P.S. and C.M., yielding maximum power outputs of 184 and 222 mW, respectively, at 1 MΩ load resistance. In contrast, R.P. exhibits peak performance at 2.5 wt%, generating 176 mW. The highest open-circuit voltage values are recorded as 1250 V for P.S., 1400 V for C.M., and 1325 V for R.P. at 50 MΩ resistance. The findings highlight that torrefied C.M. provides superior charge retention and power stability, outperforming P.S. and R.P. The study bridges a critical research gap by demonstrating the feasibility of torrefied biowaste as an eco-friendly alternative for enhancing TENG efficiency
Effect of age, cement/tailings rate, and MK-GP dosage on mechanical features and evolution mechanism of cementitious paste fill
No full textAs the cost of cemented paste fill (CPF) is a major factor limiting its further dissemination since cement-related costs are high (∼70 % of total fill costs). In contrast, metakaolin-based geopolymer (MK-GP) can partly switch cement and states superior stability/strength. This paper takes full iron mine tailings as the research object, incorporating MK-GP to substitute for part of cement and preparing a new fill type. It mostly focuses on features like age, cement/tailings (c/t) rate, and MK-GP dosage. Using uniaxial compressive strength (UCS), thermo-gravimetric analysis (TGA) and X-ray diffraction (XRD) tests, this research aims at exploring the strength evolution pattern of CPF, clarify its microscopic features, and interpret its strength response mechanism. Results specify that the strength of CPF firstly rises and later falls by growing MK-GP dosage. When MK-GP content reaches 12 %, fill's strength reaches its peak. Besides, X-ray diffraction (XRD) and thermo-gravimetric-differential thermal analysis (TG-DTA) results show that calcium hydroxide (CH) initially increases and then decreases with adding MK-GP. Backfill strength exhibits a quadratic function link with the CH content. For a MK-GP content of 12 %, the amount of CH reaches its maximum. However, when the addition number of MK-GP increases to 16 %, the trend reverses, possibly due to an excessive amount of MK-GP increasing inter-particle connections, hindering further hydration, leading to a fall in hydration products and finally causing a drop in fill strength. Lastly, this study offers new visions intended for manufacturing new fill products and afford confident references for the engineering intention of fill mix ratios at other similar mining operations
Fractal nonlocal thermoelasticity of porous mass sensor nanobeam with Klein-Gordon nonlocality subjected to blast load
No full textThis study investigates the fractal nonlocal thermoelastic behavior of porous Euler-Bernoulli nanobeams used as nanoscale mass sensors under blast loads. The nanobeam is modeled as a fractal continuum with a product-based fractal measure defined by the fractal dimension alpha, incorporating Klein-Gordon-type nonlocal elasticity to capture long-range interactions. Bernstein polynomials, applied through the Rayleigh-Ritz technique, transform the governing equations into a generalized eigenvalue problem. The eigenvalue problem is solved numerically in MAT-LAB, with solution accuracy verified through polynomial refinement and comparison with the classical Euler-Bernoulli beam model. The model evaluates the influence of porosity, boundary conditions, scaling, nonlocal, and thermal parameters on nondimensional frequency, normal stress, and displacement. Furthermore, the study highlights the significance of thermoelastic coupling in nanobeams subjected to temperature gradients and heat-shock environments, where transient thermal stresses interact with mechanical vibrations. These findings are directly relevant to thermal engineering applications, such as nanoresonators and mass sensors operating in fluctuating thermal fields, where efficient heat dissipation and thermal stability are critical for reliable performance. The proposed approach provides a reliable computational framework for analyzing coupled thermal-mechanical effects in porous nanobeams, supporting the optimal design of nanoresonators and mass sensors for thermal engineering applications
Colchicine-treated familial mediterranean fever patients are associated with a lower prevalence of mitral annular calcification
No full textObjective: Inflammation contributes to mitral annular calcification (MAC). This study aimed to evaluate the relationship between MAC and colchicine-treated Familial Mediterranean Fever (FMF). Methods: This cross-sectional study included consecutively enrolled Familial Mediterranean Fever (FMF) patients (n = 98) receiving colchicine (≥ 1 mg/day for at least one year) and controls without FMF (n = 93). FMF was diagnosed according to the Tel-Hashomer criteria. MAC was defined by transthoracic echocardiography as an echogenic structure ≥ 5 mm in thickness located at the posterior mitral annulus. Demographic, clinical, and laboratory data were recorded. Factors associated with MAC were evaluated using univariate and multivariate logistic regression analyses. Results: Among 191 participants, 13 (6.8%) had MAC. Participants with MAC were older, had higher body mass index (BMI), and showed a higher prevalence of diabetes and hypertension compared with those without MAC (all p < 0.05). Multivariate logistic regression analysis demonstrated that age (OR = 1.06, 95% CI: 1.006–1.118), BMI (OR = 1.22, 95% CI: 1.074–1.391), and the presence of FMF (OR = 0.097, 95% CI: 0.012–0.778) were independently associated with MAC. FMF showed an inverse association with the presence of MAC. Receiver operating characteristic analysis demonstrated significant predictive value for age and BMI, while FMF showed an inverse discriminatory pattern (AUC = 0.266, p < 0.001). Conclusion: Colchicine-treated patients with Familial Mediterranean Fever may be associated with a lower prevalence of mitral annular calcification, suggesting a potential long-term cardiovascular protective effect through suppression of chronic inflammation
Effect of additional light curing on color stability and degree of conversion of mono-shade resin composites
No full textThis study aims to examine the effect of additional light curing on the color stability and degree of conversion (DoC) of mono-shade resin composites cured using different light curing units and irradiation levels. Sixty-six disk-shaped samples were prepared for each of the mono-shade (Omnichroma/OC, Vittra APS Unique/VU) and multi-shade resin (Clearfil Majesty ES-2/CME) composites. The samples were randomly divided into three groups and cured for 20 s according to: (1) QTH at 800 mW/cm2 (16 J/cm2), (2) LED at 1000 mW/cm2 (20 J/cm2), and (3) 1400 mW/cm2 (28 J/cm2). After polishing, half of the samples in each group were exposed to additional light curing. Color parameters were measured at baseline and after 28 days of immersion in a coffee solution. CIEDE2000 color (∆E00) and Whiteness Index (ΔWID) changes were used to assess color stability. ∆E00 and ΔWID were compared with the perceptibility and acceptability threshold. Mono-shade composites exhibited lower DoC with higher ΔE00 and ΔWID changes compared to the multi-shade composite. Mono-shade composites showed clinically unacceptable color and whiteness changes. Additional light curing performed using the same protocol both before and after polishing did not contribute to the color/whiteness stability and DoC of either mono-shade or multi-shade resin composites
Intelectin-1 and systemic inflammation indices as potential biomarkers in alzheimer's disease
No full textAlzheimer's disease (AD) is a progressive neurodegenerative condition marked by amyloid-beta deposits, tau pathology, chronic systemic inflammation, and metabolic disturbances. Recent evidence highlights the relevance of inflammatory markers and adipokines as practical blood-based biomarkers in AD diagnosis. In this cross-sectional study, 70 patients with probable AD and 50 healthy controls matched for age and sex were evaluated. Cognitive performance was measured using the Standardized Mini Mental Test (SMMT). Serum intelectin-1 (ITLN1) and tumor necrosis factor-alpha (TNF-alpha) levels were analyzed, and hematologic indices were used to calculate the Systemic Immune-Inflammation Index (SII), Systemic Inflammation Response Index (SIRI), and CALLY index. Compared to controls, individuals with AD exhibited significantly lower ITLN1, albumin, lymphocyte counts, and CALLY index, while CRP, neutrophil and monocyte counts, SII, and SIRI were notably higher. TNF-alpha concentrations showed no significant difference between groups. ITLN1 and CALLY levels correlated positively with SMMT scores, whereas SII and SIRI correlated negatively. ROC analysis indicated that ITLN1 (AUC = 0.764), CALLY (AUC = 0.754), SII (AUC = 0.734), and SIRI (AUC = 0.787) had moderate discriminatory ability. This study suggests that reduced ITLN1 and increased systemic inflammation indices are associated with AD and may reflect underlying metabolic and inflammatory pathways involved in disease progression. Although TNF-alpha levels were variable, ITLN1, SII, SIRI, and CALLY indices demonstrated potential as peripheral biomarkers to help distinguish patients with AD. Future large-scale prospective research is needed to further clarify their clinical utility
Thematic evolution of educational technology research: a large-scale topic modeling perspective
No full textThis study aims to reveal the thematic evolution of the educational technology field by analyzing 17,393 articles published between 2000 and 2024 in ten leading journals using the Latent Dirichlet Allocation (LDA) based topic modeling. Based on the analysis of title, abstract, and keywords, 20 themes were identified and grouped under seven broader meta-themes such as “Teacher Professional Competence and Technology Adoption”, “Digital and Disciplinary Literacy Development”, and “Immersive and Experiential Learning Technologies”. The model achieved its highest coherence at K = 20 (c_v = 0.4091), and the stability of the thematic structure was supported through additional runs with alternative hyperparameter configurations and expert validation. The findings show that there has been a significant increase in themes such as “Technology Integration”, “Teacher Roles in Online Learning Design”, and “Technology Acceptance and Self-Efficacy” in recent years. Temporal trend and growth analyses indicate that these themes will continue to shape the research landscape in the upcoming years. This holistic approach, which overcomes the contextual limitations of traditional bibliometric analysis, makes a significant contribution to the literature by mapping the last 25 years of scholarly accumulation in educational technology
Data Preparation for Analysis- continue
No full textData Mining 3. Hafta Ders Notu Konusu : Data Preparation for Analysis- continu
Çayda Fidan Üretimi ( Generatif Çoğaltma)
No full textÇay Tarımı Dersi 4. Hafta Ders Notu Konusu : Çayda Fidan Üretimi ( Generatif Çoğaltma