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, Evaluation of Temperature Rise within Articulating Surfaces of Artificial Hip Joint Materials
No full textExamine the Levels of Relational Resilience, Marital Self-Efficacy And Trust in Dyadic Relationships According to Certain Demographic Variables Among Married İndividuals
No full textCunda Adası Geleneksel Kent Dokusu ve Mimarisi Dünden Bugüne, Bugünden Geleceğe Sürdürülebilirlik
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Evaluating organ-specific radiation exposure in transcatheter arterial chemoembolization (TACE): A phantom-based assessment of safety thresholds for interventional radiology applications
No full textObjective: This study aims to evaluate radiation doses absorbed by critical organs during Transcatheter Arterial Chemoembolization (TACE) using Thermoluminescent Dosimeters (TLDs) placed within an Alderson Rando Phantom, and to assess these doses against established safety limits. Method: The Alderson Rando Phantom, known for its anatomical accuracy, was used to simulate radiation exposure during TACE procedures. TLDs were strategically positioned in the stomach, kidneys, liver, spleen, pancreas, vertebrae, and reproductive organs. The TLDs were calibrated with a Cs-137 gamma source, and measurements were taken using a Siemens Artis Zee C-arm system. Radiation doses were analyzed and compared to safety thresholds from clinical guidelines. Results: Our findings indicate that the average dose to critical organs remained within safe limits, with the liver receiving 32.75 ± 0.065 mSv and kidneys 88.48 ± 12 mSv. While doses for organs close to the target liver region were higher, all remained below tolerance thresholds. Conclusion: This study demonstrates that TACE can be performed safely with controlled radiation exposure to adjacent organs when proper protocols are followed. The Alderson Rando Phantom proved effective in simulating patient exposure, providing critical insights for enhancing radiation safety in interventional radiology
Radiation dose variability in critical thoracic organs during CT imaging: A multi-centre phantom dosimetry study
No full textThis multicenter phantom-based study quantified organ-specific radiation doses delivered during routine thoracic CT using five clinical systems from four major manufacturers. A total of 70 TLD-100 dosimeters were calibrated and strategically positioned in an Alderson Rando® phantom to measure absorbed doses in the lungs, heart apex, atrium, and bilateral breasts. Marked dose variability was observed across scanners, driven by differences in tube current, CTDIvol, pitch, and the implementation of dose modulation strategies. Lung doses ranged from 4.60 to 22.51 mGy, heart apex doses from 4.15 to 23.15 mGy, atrial doses from 4.73 to 20.77 mGy, and breast doses from 3.17 to 22.01 mGy. The CT-2 system consistently yielded the highest organ doses, while the CT-1 demonstrated the most effective dose reduction. Comparative assessment with literature confirmed strong alignment of our measured values with published experimental and Monte Carlo-based studies. It can be concluded that significant dose reductions to radiosensitive thoracic organs are achievable through advanced modulation technologies and tailored protocol adjustments
Linking positive childhood experiences to young adults' communication and problem-solving skills: The mediating role of self-confidence
No full textPositive experiences in early life stages are increasingly recognized as foundational elements that shape individuals' psychological resources and social competencies throughout adulthood. This study examined the impact of positive childhood experiences on young adults' communication and problem-solving skills, focusing on the mediating role of self-confidence. Participants included 696 university students (580 females, 116 males; M age = 22.1), who completed validated measures of positive childhood experiences, self-confidence, communication, and problem-solving. Structural equation modeling revealed that the influence of positive childhood experiences on communication and problem-solving skills was entirely indirect, fully mediated by selfconfidence, with no significant direct effects. Additionally, self-confidence significantly predicted both skills. A gender difference favoring females was found only in communication skills. These findings underscore the importance of fostering self-confidence as a developmental outcome of positive early experiences and contribute to understanding how childhood shapes essential competencies in emerging adulthood
Comprehensive life cycle assessment of cocoa and chocolate supply chains: Environmental sustainability perspectives
No full textBackground: Cocoa and chocolate products form a globally significant agri-food chain with substantial economic, cultural, and nutritional value. However, their production and processing are associated with pronounced environmental impacts, primarily due to resource-intensive cocoa farming, complex international supply networks, and energy-demanding manufacturing processes. Life Cycle Assessment (LCA) has become a widely used tool to quantify these impacts, but issues related to data gaps, methodological inconsistencies, and limited scope still constrain its effectiveness. Scope and approach: This review provides a comprehensive analysis of LCA applications across the cocoa and chocolate supply chains, adopting a cradle-to-grave perspective that encompasses cultivation, processing, packaging, distribution, consumption, and end-of-life phases. Emphasis is placed on methodological evolution, including the integration of hybrid-LCA and multi-regional input-output (MRIO) models. In addition, the review examines challenges related to system boundaries, functional units, co-product allocation methods, and the incorporation of circular economy principles, social LCA (S-LCA), and life cycle costing (LCC). Key findings: Cocoa cultivation and industrial chocolate production are consistently identified as the main contributors to environmental burdens, particularly in terms of greenhouse gas emissions, human toxicity, and cumulative energy demand. Agricultural practices including conventional, organic, and agroforestry systems strongly influence environmental performance. However, limited field-level data, inconsistent methodological choices, and insufficient attention to socio-economic dimensions hinder the comparability and policy relevance of current studies. Recent efforts toward by-product valorization, such as the conversion of cocoa pod husks into bio-based materials or chemicals, offer promising eco-efficiency gains but remain underexplored in LCA frameworks. Conclusions and future perspectives: Improving the robustness and applicability of LCA in the cocoa sector requires harmonization of functional units, better allocation procedures, and enhanced data collection across diverse production systems. Integrating hybrid-LCA and MRIO approaches can better capture indirect environmental burdens in globalized supply chains. Future studies should also consider circular economy strategies, socio-economic trade-offs, and consumer behavior during product use and end-of-life stages to enable a more holistic understanding of sustainability performance. These advancements will support evidence-based decision-making for industry and policymakers and contribute to the development of resilient, low-impact cocoa and chocolate supply systems aligned with global sustainability goals
