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A bio-inspired approach to sustainable building design optimization: Multi-objective flow direction algorithm with one-hot encoding
No full textThe urgent need for sustainable building design calls for advanced optimization methods that simultaneously address economic and environmental objectives, particularly those involving mixed discrete-continuous variables such as insulation material, heating source, and insulation thickness. While nature-inspired metaheuristics have shown promise in engineering optimization, their application to building envelope design remains limited, especially in handling discrete choices efficiently within a multi-objective framework. Inspired by the natural process of rainwater runoff and drainage basin dynamics, this study presents a novel hybrid approach integrating the Multi-Purpose Flow Direction Algorithm (MOFDA) with One-Hot Encoding to optimize external wall insulation. This bio-inspired algorithm mimics how water seeks optimal paths across terrain, enabling effective navigation of complex design spaces with both categorical and continuous variables. The model aims to minimize total lifecycle costs and CO2 emissions across T & uuml;rkiye's six updated climatic regions. Pareto-optimal solutions are created using MOFDA, after which the Complex Proportional Assessment (COPRAS) method, weighted by Shannon Entropy, selects the most balanced designs. The results reveal significant climate-dependent variations: in the warmest region, the cost-optimal thickness is 3.3 cm (Rock Wool), while the emission-optimal reaches 17.3 cm (Glass Wool). In colder regions, emission-driven scenarios consistently require up to 40 cm insulation, indicating a practical limit of current materials. Under balanced weighting, fuel preferences shift from LPG in milder climates to Fuel Oil in harsher climates. Notably, Shannon Entropy assigned a weight of 88-92% to emissions due to their wider variability across the Pareto front, underscoring the environmental priority in data-driven decisions. This study demonstrates that the bio-inspired MOFDA framework, enhanced with One-Hot Encoding, effectively handles mixed discrete-continuous optimization and provides a robust, climate-aware decision tool for sustainable building design, reinforcing the value of translating natural flow processes into engineering solutions
Modelling of groundwater salt pollution in semi-arid watershed disturbed by agricultural activities: Lake tuz (Salt Lake) basin, Turkey
No full textThis paper aimed at modelling and investigating a groundwater salt pollution/contamination in the Lake Tuz (Salt Lake) Basin (29,425 km2, Central Anatolia, Turkey), in which intensive agricultural activities have been applied throughout the years, in addition to the natural resources (salty lakes). MT3DMS was used by utilizing the groundwater flow model of Eryigit (2025) to simulate the groundwater salt pollution of the watershed under transient conditions. The input files of MT3DMS were generated by GMS groundwater simulator. The model was yearly simulated for 19 years from 2000 to 2018. Model calibration and validation were carried out by using groundwater quality observation data of 2000-2012 and 2013-2018, respectively. Electrical conductivity (mu S/ cm) data were converted to Total Dissolved Solids (g/l) for representing a salinity (as a salt concentration). To improve parameter estimations, the groundwater model parameters were calibrated by the modified Clonal Selection Algorithm (a class of Artificial Immune Systems) linked with MT3DMS in MATLAB. Recharge concentration was calibrated based on the land use/cover (30 different types) while other parameters (porosity, longitudinal dispersivity, sorption) were calibrated depending on the aquifer lithology (23 aquifers). Furthermore, the groundwater contaminant transport model was run to estimate groundwater salt concentrations within the scenario based on increasing agricultural activities in the future. Owing to/thanks to the model, predictions of the groundwater salt pollution depending on both anthropogenic (agriculture) and natural (lakes) factors were performed in the Lake Tuz watershed for the first time as a largest scaled spatiotemporal groundwater quality (salinity) model with a long simulation period (19 years) in Turkey.Bolu Abant Izzet Baysal University Coordination Unit of Scientific Research Projects
2023-BDP-6.12.54-000
Evaluation of patients admitted to the pediatric emergency departments due to suicide attempts: A multicenter study from Türkiye
No full textBackground: Suicide is a major cause of morbidity and mortality in adolescents and is increasingly recognized among younger children. Pediatric emergency departments (EDs) are critical points for the identification and management of suicide attempts. This study aimed to evaluate the demographic and clinical characteristics, methods, and temporal trends of suicide attempts among children and adolescents presenting to pediatric EDs in T & uuml;rkiye. Methods: We conducted a retrospective, multicenter study across 29 pediatric EDs from July 1, 2017, to June 30, 2022. Patients aged 8-18 years with a confirmed suicide attempt were included. Data collected included demo-graphics, methods, psychiatric history, prior attempts, medications used in self-poisoning, psychiatric consulta-tions, and outcomes. Statistical analyses included chi-square and Mann-Whitney U tests. Results: During the study period, 6004 suicide attempt presentations were identified among 9,736,825 ED visits (0.5/1000). The median age was 15 years (IQR: 14-16), with 78.8% female (female-to-male ratio 3.7:1). Most pa-tients (92.9%) were aged 13-18 years. Self-poisoning was the predominant method (95.4%), commonly involving NSAIDs, paracetamol, SSRIs, and atypical antipsychotics; 23.5% ingested their own medications, 76.2% of which were psychotropics. A known psychiatric disorder was present in 36.4%, and 16.4% had a prior suicide attempt. Psychiatric consultation was obtained in 73% of cases. Hospitalization occurred in 89.8%, with 15.5% requiring in-tensive care. Eleven deaths were recorded. Conclusions: Suicide attempts among children and adolescents are a significant and ongoing public health problem in T & uuml;rkiye, with self-poisoning as the dominant method. The findings underscore the need for targeted prevention strategies, safe medication storage, and strengthened psychiatric services in pediatric EDs to improve outcomes for this high-risk population. (c) 2026 Elsevier Inc. All rights are reserved, including those for text and data mining, AI training, and similar techologies
Exact analytical solutions of the modified complex ginzburg-landau equation: Multi-waves, bright and dark solitons via systematic integration approaches
No full textIn this study, we present the derivation of exact solutions for the modified complex Ginzburg-Landau (mCGL) equation. This equation is one of the models in plasmas, optical systems and spatially extended nonequilibrium media. Pursuing the Kumar-Malik ansatz, multi-wave expansion and dynamical phase-space analysis, we systematically construct many families of solutions. The Kumar-Malik method furnishes Jacobi elliptic solutions and hyperbolic and trigonometric forms. In this regard, we capture soliton solutions, including singular periodic, bright, dark, kink, anti-kink and singular waveforms. On the other hand, the multi-wave approach presents a rational solution that defines wave interaction, while dynamical analysis reveals bright and dark solitons through Hamiltonian phase portraits. 3-D, density and time plot profiles demonstrate the physical meanings of the exact solutions. With the examined analytic techniques, other nonlinear phenomena in diverse physical systems, such as optical communications, Bose-Einstein condensates and ultrafast laser systems can be investigated
Vascular access for hemodialysis and catheter-related bloodstream infections: A survey on preventive measures and treatment strategies by the epdwg and espn dialysis working group
No full textThe choice of vascular access (VA) plays a key role in the success of hemodialysis (HD). Despite their widespread use, central venous catheters (CVCs) are associated with higher rates of dysfunction, thrombosis, and catheter-related bloodstream infections (CRBSI). We investigated current practices in pediatric HD across European pediatric nephrology centers, focusing on VA choices, infection control measures, and CRBSI management. An online questionnaire was e-mailed to 119 members of the European Society for Pediatric Nephrology (ESPN) Dialysis Working Group and European Pediatric Dialysis Working Group (EPDWG). Descriptive statistics were used to summarize practices across centers, comparative analyses between centers in countries with Human Development Index (HDI) > 0.90 and < 0.90. Thirty-one centers across Europe participated in the survey. CVCs were the primary VA in 73.1% of the centers. Twenty (66.7%) centers reported malfunction as the most common CVC complication, followed by catheter thrombosis (19.4%) and CRBSI (12.9%). The diagnostic approach for CRBSI varied widely, with 35.4% of centers relying on a single positive catheter culture, while 57.9% did not collect a second culture from the peripheral vein or HD circuit. The most common empirical treatment was glycopeptides combined with third-generation cephalosporins. Nearly all centers used intravenous antibiotics for less than 3 weeks, and over half modified lock solutions with antibiotics following CRBSI diagnosis. Catheter removal practices were inconsistent, even in cases of severe infection. Centers reported a total of 548 HD patients. Exit-site infections and CRBSI were observed in 98 (17.8%) and 155 (28.2%) patients, respectively. CRBSI rates and CRBSI-related catheter replacements were significantly higher in centers from countries with HDI < 0.90 and in centers without a dedicated pediatric HD unit. Conclusion: The suboptimal adherence to current VA recommendations and wide variability in catheter care practices including the prevention, diagnosis, and management of CRBSI highlight the need for standardized pediatric-specific protocols to enhance catheter longevity and improve patient outcomes. What is Known: center dot Central venous catheters are widely used in pediatric hemodialysis but carry a high risk of complications, especially catheter-related bloodstream infections (CRBSI). What is New: center dot This multinational survey reveals significant variability in vascular access selection, CRBSI prevention, diagnosis, and treatment across European pediatric hemodialysis centers, with clear disparities by national HDI levels. center dot The findings highlight the need for standardization of vascular access care and CRBSI management and evidence-based pediatric-specific guidelines.Gazi Üniversites
Suva-based modelling of thmfp under ozonation using regression and ann approaches
No full textDrinking-water treatment systems must effectively control natural organic matter (NOM), a major precursor of regulated disinfection by-products (DBPs). Specific ultraviolet absorbance (SUVA) is widely used as an operational surrogate for NOM aromaticity and hydrophobicity; however, ozonation and subsequent filtration can disrupt the linear relationship between SUVA and trihalomethane formation potential (THMFP). This study evaluates whether SUVA can reliably predict THMFP under two ozonation configurations frequently applied in drinking-water treatment: pre-ozonation prior to coagulation-filtration and final ozonation following filtration. Experimental data were analyzed using conventional linear regression and artificial neural network (ANN) models, with SUVA employed as the sole predictor variable. Across all treatment configurations, reductions in SUVA were consistently more pronounced than corresponding decreases in THMFP, indicating a decoupling between chromophoric loss and chlorine-reactive precursor dynamics under ozonation-dominated conditions. Linear regression models exhibited only moderate predictive performance (R2 = 0.63-0.76), reflecting the limitations of proportional surrogate-based approaches when NOM undergoes oxidative and adsorptive transformation. In contrast, single-parameter ANN models captured the nonlinear SUVA-THMFP relationship with substantially higher accuracy across both pre- and final-ozonation regimes (R2 = 0.88-0.99), successfully resolving process-dependent patterns embedded within optically compressed SUVA signals. These findings demonstrate that, although SUVA alone cannot linearly represent the multistep transformation of NOM during ozonation and adsorption, it retains process-relevant structure information on DBP precursor reactivity that can be effectively extracted using nonlinear modelling. The results highlight the potential of integrating ANN-driven tools into advanced monitoring and DBP-control strategies in modern drinking-water treatment systems
Development, mechanical characterization and analysis of modified cellulose nanofiber reinforced thermoplastic polymer composite materials
No full textOtomotiv endüstrisinde geleneksel olarak kullanılan polimerler, güncel araç teknolojilerinin talep ettiği ileri mekanik ve fiziksel performans kriterlerini karşılamada yetersiz kalmaktadır. Bu kısıtları gidermek amacıyla geliştirilen petro-kimya türevli takviye elemanları ise; yüksek özgül ağırlık, üretim kompleksliği ve sınırlı geri dönüşüm olanakları gibi kronik dezavantajları bulunmaktadır. Bu çerçevede; düşük yoğunluk, biyobozunurluk ve yüksek mukavemet/ağırlık oranı gibi üstün karakteristik özelliklere sahip bitkisel kökenli doğal fiberler, sürdürülebilir ve yüksek performanslı polimer kompozitlerin geliştirilmesinde iyi bir alternatif olarak öne çıkmaktadır. Bu çalışmada tamamen doğal ve bitkisel kaynaklardan elde edilen nanoselüloz fiber takviyeli polipropilen (PP) kompozitler geliştirilmiştir. Hidrofilik nanoselüloz fiberler hidrofobik PP matris içerisinde homojen bir şekilde dağılabilmesi için sililasyon işlemi ile modifiye edilmiştir. Belirlenen takviye oranlarında fiber ve matris malzemeler ekstrüzyonla karıştırılmış ve karakterizasyon testlerine uygun standartlarda enjeksiyon kalıplama tekniği ile numune haline getirilmiştir. Üretilen kompozit malzemelerin karakterize edilmesi amacıyla mekanik, morfolojik ve termal özellikleri incelenmiştir. Ayrıca geliştirilen kompozit malzemelerin mekanik özelliklerinin teorik sınırlarını belirlemek amacıyla teorik ve sayısal malzeme modelleri kullanılarak analizler gerçekleştirilmiştir. Yapılan testler sonucunda nanoselüloz fiberlerin takviye elemanı olarak kullanımının polipropilen matrisin mekanik özelliklerini iyileştirdiği görülmüştür. Silan ajanı ile yapılan modifikasyonların ise daha güçlü bir fiber-matris arayüzey etkileşimi sağlayarak morfolojik açıdan düzgün, termal olarak kararlı ve işlenebilir kompozitler üretilmesine olanak tanıdığı belirlenmiştir. Mekanik testler sonucunda; fiber takviyeli PP kompozitlerin elastisite modülünde %43, çekme mukavemetinde ise %15 oranında artış kaydedilmiştir. Buna karşın, kopma uzama değerlerinde %83’e varan belirgin belirgin bir düşüş tespit edilmiştir. Bu çalışma nanoselüloz fiber gibi doğal takviye elemanlarının otomotiv sektöründeki uygulanabilirliğini artırmak ve potansiyel kullanım alanlarını genişletmek adına atılmış önemli bir adım olarak değerlendirilmektedir.Polymers traditionally used in the automotive industry are insufficient to meet the advanced mechanical and physical performance criteria demanded by current vehicle technologies. Petrochemical-derived reinforcement elements developed to overcome these limitations suffer from chronic disadvantages such as high specific gravity, production complexity, and limited recycling possibilities. In this context, plant-derived natural fibers, possessing superior characteristics such as low density, biodegradability, and high strength-to-weight ratio, stand out as a good alternative in the development of sustainable and high-performance polymer composites. In this study, nanocellulose fiberreinforced polypropylene (PP) composites obtained from entirely natural and plant-based sources were developed. Hydrophilic nanocellulose fibers were modified via the silylation process to ensure homogeneous dispersion within the hydrophobic PP matrix. Fiber and matrix materials were mixed by extrusion at specified reinforcement ratios and fabricated into specimens using the injection molding technique in accordance with characterization test standards. The mechanical, morphological, and thermal properties were investigated to characterize the produced composite materials. Furthermore, analyses were performed using theoretical and numerical material models to determine the theoretical limits of the mechanical properties of the developed composite materials. As a result of the tests, it was observed that the use of nanocellulose fibers as a reinforcing agent improved the mechanical properties of the polypropylene matrix. It was determined that the modifications performed with the silane agent enabled the production of morphologically uniform, thermally stable, and processable composites by providing a stronger fiber-matrix interfacial interaction. Following the mechanical tests, an increased of 43% in the modulus of elasticity and 15% in the tensile strength of the fiber-reinforced PP composites was recorded. In contrast, a significant decrease of up to 83% was detected in the elongation at break values. This study is considered a significant step towards increasing the applicability of natural reinforcements, such as nanocellulose fibers, in the automotive sector and expanding their potantial areas of use
Image-based nutritional assessment: Evaluating the performance of chatgpt-4o on simple and complex meals
No full textThis study presents an exploratory pilot evaluation of the ChatGPT-4o artificial intelligence model in estimating energy and macronutrient content from images of meals with different levels of complexity: simple, moderate, and complex. Classifications were based on ingredient distinguishability, the presence of visually undetectable elements such as oil, sauce, or filling, and the overall variety of ingredients. Nine food items representing the three complexity levels were photographed under standardized natural lighting and uploaded to ChatGPT-4o. After initial predictions, additional content information was provided for selected samples, and second estimations were obtained. Predicted values were compared with reference values calculated by the researchers. Initial predictions showed substantial deviations, with errors reaching 54.4 % for energy and 76.5 % for fat, particularly in complex meals and those with visually obscured fat. Providing additional information was associated with improved accuracy for all macronutrients, with the R2 for energy increasing from 0.591 to 0.941. Although these findings demonstrate that supplementary contextual information can enhance model performance, they represent preliminary, descriptive observations based on a small pilot dataset. Accordingly, the results should not be generalized or interpreted as evidence of readiness for real-world dietary planning, but rather as an initial feasibility indication requiring further validation with larger and more diverse samples
Bacterial chemotaxis in molecular communication: Experimental and simulation analysis of receiver placement and gradient dynamics
No full textBacteria-based nanonetworks (BNs) represent a promising strategy for nanoscale information transfer, utilizing bacterial motility and chemotaxis for targeted message delivery. This study analyzes BN performance through both experimental validation and a custom-developed three-dimensional (3D) simulation program built in MATLAB, focusing on receiver (RX) placement, chemoattractant release rate (Q), and bacterial lifespan. The simulation employs experimentally validated parameters and models bacterial behavior under various spatial configurations. Results demonstrate that RX positioning significantly affects communication efficiency, with asymmetric placement causing uneven chemoattractant gradients and reduced success rates. While higher Q values improve reach time and delivery success, bacterial lifespan becomes a limiting factor at extended distances. Experimental findings using agar-based assays confirm a threshold distance beyond which bacterial motility becomes ineffective. These insights provide practical guidance for optimizing BN systems by balancing signal strength with biological constraints. Future work should explore adaptive bacterial strategies and dynamic environmental conditions to further enhance BN reliability and applicability in areas such as targeted drug delivery and biosensing
An analytical study of the time-fractional extended shallow-water wave equation in (3+1)-dimension with two different derivatives and their comparison
No full textIn ocean physics, an essential mathematical framework for examining the dynamic behavior of waves is the (3 + 1)-dimensional generalized shallow-water wave equation. This approach is driven by the growing need to incorporate nonlinear and anomalous behaviors shallow-water wave propagation into more realistic mathematical models. This motivation is a key consideration for improving coastal hazard prediction, mitigating tsunami impacts, optimizing renewable energy extraction, and deepening our understanding of complex coastal processes. In this paper, exact solutions of the fractional generalized shallow-water wave equation are constructed using two alternative methods: the extended modified auxiliary equation mapping method and the F-expansion approach. The extended modified auxiliary equation mapping method yielded nineteen exact solutions across two main sets, while the F-expansion method produced solutions for seventeen different cases. To visualize these, 2D and 3D graphical representations have been generated for several solutions using fractional parameter values alpha is an element of (0, 1], including sample values such as 0.2, 0.5, 0.7, and 0.78, to illustrate how the order of the derivative affects the soliton profile. The results show that decreasing alpha leads to broader and smoother soliton structures. Finally, the modulation instability of the governing model is also investigated, confirming that the established results are stable