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Development, characterization, and in vitro evaluation of co‑drug encapsulated, targeted theranostic liposomes for osteomyelitis
No full textDesigning a novel FeCoNiMnCu high-entropy Alloy: Synthesis, structural evolution, magnetic behavior, and radiation shielding performance
No full textIn this study, a novel FeCoNiMnCu HEA was synthesized via mechanical alloying and exhibited a single-phase face-centered cubic (FCC) structure with a crystallite size of 11.7 nm and a lattice strain of 0.81 %. Magnetic characterization revealed soft ferromagnetic behavior with a saturation magnetization of 32 emu/g at 300 K, increasing to 53 emu/g at 10 K. The alloy demonstrated excellent gamma-ray attenuation, with lower half-value layer (HVL) and mean free path (MFP) values than conventional shielding materials. Notably, its fast neutron removal cross-section (Sigma R = 0.1654 cm- 1) outperformed standard materials such as B4C, graphite, and water in the fast neutron energy range. These findings underline the multifunctional performance of FeCoNiMnCu HEA, highlighting its strong potential for use in advanced nuclear reactor components and radiation shielding technologies
Dose- and Time-Dependent Halofuginone Cytotoxicity in HaCaT Keratinocytes: Implications for Cholesteatoma
No full textVariation of radiation-induced effects in poly(epichlorohydrin-co-ethylene oxide-co-allyl glycidyl ether) (GECO) terpolymers as a function of molecular and structural architecture
No full textThe aim of this study was to investigate how radiation-induced effects vary in poly (epichlorohydrin-co-ethylene oxide-co-allyl glycidyl ether) (GECO) terpolymers based on their molecular and structural architecture. To modify the molecular and structural features, we examined GECO terpolymers with different molecular weights and varying ratios of epichlorohydrin (ECH), ethylene oxide (EO), and allyl glycidyl ether (AGE) in their chain structure. Polymers were irradiated at room temperature with accelerated electrons within an absorbed dose range of 0-100 kGy. Before analyzing the effects of ionizing radiation on the terpolymers, a comprehensive characterization of GECO terpolymers was performed using spectroscopic and chromatographic methods. Additionally, previously unknown physicochemical parameters, such as the solubility parameter and Mark-Houwink constants, were identified. The effects of irradiation on the chain structure of the terpolymers were examined using sol-gel, rheological, and spectroscopic methods. It was found that all terpolymers rapidly undergo cross-linking up to a certain dose. Beyond this dose, there is a slight chain scission as the dose increases; however, the gelation percentage up to 100 kGy remains mostly unchanged. It has been observed that the gelation tendency of GECO terpolymers depends on their molecular structure, and the gelation ratio increases with the increase in the AGE content. Using the Charlesby-Pinner and Charlesby-Rosiak equations for each terpolymer, the chain scission and crosslink yield ratio (po/qo), gelation dose (Dg), and virtual gelation dose (Dv) were determined and the effect of ionizing radiation on these terpolymers-whose use has increased in recent years-was analyzed. This study also examined the impact of ionizing radiation on physicochemical parameters such as the Flory constant and solubility parameter, as well as the changes induced in the chemical structure through swelling analyses and spectroscopic analyses, respectively. As a result of the interaction with radiation, the changes observed in the chemical structure particularly in chloride, allyl, and methyl groups were evaluated using FTIR, and a mechanism was proposed for how GECO terpolymers can be cross-linked through radiation
The Key Role of Communication in Principals' Sensemaking Competencies in Enhancing School Effectiveness
No full textThis study aims to explore the mediating role of principals' communication skills in the relationship between their sensemaking competencies and school effectiveness. The hypothesized model was tested with a correlational research design using Structural Equation Modeling. The stratified sample involved 648 Turkish teachers in the central districts of Erzurum, T & uuml;rkiye. Results indicate that principals' sensemaking competencies significantly predict school effectiveness, with communication skills acting as a partial mediator in this relationship. High levels of both skills are associated with improved school performance, better student outcomes, and a positive school climate. The study reveals that Turkish principals' superior sensemaking and communication skills are strongly linked to enhanced school effectiveness, emphasizing the need for targeted, context-specific professional development. These findings suggest that incorporating these competencies into hiring and training practices could significantly improve leadership outcomes and overall school effectiveness
Turkish Science Curriculums Reloaded: Epistemic Practice Demands in the Newly Released Curricular Documents
No full textThis study investigated the integration of epistemic practices in the 2024 Turkish science curriculums for grades 3-8, addressing the global shift toward a science-as-practice (epistemic turn) approach that positions students as epistemic agents engaged in practices like data analysis, argumentation, and reasoning. Using a novel, epistemically oriented taxonomy, the study analyzed 745 learning outcomes to assess the distribution and alignment of epistemic practice demands with students’ cognitive and epistemic development. Findings revealed that while the curriculums incorporate 40 distinct epistemic practices (e.g., data gathering, model construction, inductive reasoning, classifying, control-of-variables, evidence-based reasoning, identifying logical fallacies, experimenting, interrogating), their distribution was inconsistent and misaligned with students’ developmental stages. Lower-order practices (e.g., perception and conception) dominated, while higher-order practices (e.g., causation, argumentation, and abstraction) were underrepresented, potentially hindering students’ progression toward advanced epistemic cognition. The study underscored the need for a balanced, developmentally sensitive curriculum design that progressively challenges students’ epistemic capacities. The coding catalog developed in this study may serve as a methodological tool for researchers and curriculum developers, enabling cross-country comparisons and informing curricular revisions. Future research should explore the implementation of these practices in authentic classroom settings and examine the gap between curricular intentions and instructional realities.</p
Ultrasound-Guided Suprapatellar Pouch vs. Medial Midpatellar Injection: A Cadaveric Validation.
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Radiopharmaceuticals in Renal Imaging: A Comprehensive Review of Current Applications and Future Prospects
No full textThe kidneys play a vital role in filtration, excretion, and metabolic regulation, making accurate functional assessment essential for diagnosis, monitoring, and management of renal diseases. While conventional imaging modalities such as ultrasonography, computed tomography (CT), and multiparametric magnetic resonance imaging (MRI) provide structural and functional information, nuclear medicine techniques enable more detailed evaluation of renal physiology at the molecular level. This review provides a comprehensive overview of functional renal imaging using both conventional renal scintigraphy and emerging positron emission tomography (PET) radiopharmaceuticals. Established renal scintigraphy radiopharmaceuticals, including 99mTc-DTPA, 99mTc-DMSA, 99mTc-MAG3, and 99mTc-EC, have long been applied to assess glomerular filtration rate (GFR) and effective renal plasma flow (ERPF). PET radiopharmaceuticals, offering higher sensitivity, superior quantification, and molecular insight, are increasingly investigated for similar purposes, with 68Ga-EDTA, 68Ga-DTPA, 68Ga-NOTA, 68Ga-DOTA, and 18F-FDS for GFR assessment and 11C-PABA, 18F-PFH, Re(CO)3(18F-FEDA), and Al-18F-NODA-butyric acid for ERPF evaluation. Additional PET tracers, including 68Ga-IRDye800-tilmanocept, 18F-FDG, and 68Ga-PSMA-11, have been explored for glomerular mesangial function, renal tumors, and split renal function, respectively. By systematically summarizing both renal scintigraphy and PET approaches, this review highlights current and emerging PET radiopharmaceuticals for renal functional imaging and discusses their potential clinical applications and future perspectives in precision nephrology
