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Production and characterization of alumina doped sheep and synthetic hydroxyapatite bioinks
No full textThis study presents the formulation and evaluation of composite bioinks incorporating synthetic hydroxyapatite (CSHA), sheep-derived hydroxyapatite (SHA), and alumina (Al2O3) for extrusion-based 3D bioprinting of bone scaffolds. Rheological analyses demonstrated shear-thinning behavior, with both CSHA/Al2O3 and SHA/Al2O3 exhibiting comparable viscosity profiles between 400 and 1000 s(-)(1), indicating their suitability for stable extrusion. The bone scaffolds were fabricated using a single-syringe extrusion-based bioprinter. After the printing process, the scaffolds were dried and then immersed in simulated body fluid (SBF) to evaluate their in vitro bioactivity. This immersion process was carried out under static conditions at 36.5 degrees C for 28 days. SEM and EDS analyses revealed denser apatite nucleation on CSHA/Al2O3 scaffolds (Ca/P = 1.33) compared to SHA/Al2O3 (Ca/P = 0.88), confirming enhanced bioactivity. FTIR analysis detected characteristic phosphate and carbonate bands indicative of bone-like apatite formation. Cell viability and cytocompatibility were assessed using MTT and WST-1 assays with L929 fibroblasts and osteoblasts. While fibroblast viability showed no significant difference (p > 0.05), CSHA/Al2O3 scaffolds promoted significantly higher osteoblast viability (p < 0.05). Confocal microscopy confirmed sustained osteoblast proliferation at 36 h. These findings demonstrate that CSHA/Al2O3-based bioinks possess favorable printability, mineralization potential, and osteogenic support, making them strong candidates for future bone tissue engineering applications using ceramic-reinforced bioprinting strategies
Greener and scalable MXene fabrication enabled by supercritical CO<sub>2</sub>: a mini-review
No full textSupercritical CO2 (scCO2) has a gas-like diffusivity and a liquid-like density, which speeds up transport and allows for tunable termination chemistry during MXene synthesis. This mini review compares scCO2-assisted routes to HF and LiF-HCl systems in terms of time to conversion, monolayer yield, oxidation stability, and readiness for scale-up. Optimized scCO2 protocols show a conversion time of about 0.5 to 3 hours (compared to 12 to 72 hours), a mono/few-layer yield of more than 60%, and better air stability, with kilogram-scale batches presented. We evaluate the effects of pressure, temperature, water activity, and co-solvent polarity, and we demonstrate how RESS blow-down and in situ spectroscopy can speed up the process. Application snapshots (supercapacitors, Li/Na-ion batteries, HER, EMI) demonstrate consistent improvements due to termination control and diminished restacking. There are still route-specific limits, comprising narrow p-T windows, batch-to-batch termination scatter, and compression/heat duties that set techno-economics. We suggest a reporting checklist that includes PMI, E-factor, specific energy, CO2 intensity, and water use. We also describe hybrid scCO2-electrochemical/microwave pathways and closed-loop engineering that are needed to connect the promise of lab-scale research with real-world use. When looked at with clear, metrics-based criteria, scCO2 is a safer, greener, and more scalable way to make MXene
A generalized hybrid machine learning framework for predicting biohydrogen production via dark fermentation of organic wastes
No full textThe rising global demand for sustainable energy has directed significant attention towards biohydrogen production via dark fermentation of organic wastes. Accurate yield prediction is crucial for optimizing process conditions and enhancing overall process. This study aims to develop a robust and interpretable predictive framework that integrates kinetic modeling with a hybrid Bayesian Optimization–Artificial Neural Network (BO–ANN) approach for precise biohydrogen yield prediction. The core novelty lies in representing each substrate not as a simple category, but by its quantitative kinetic parameters from the Modified Gompertz equation, providing a biologically meaningful input. A comprehensive database compiled from the literature incorporates key process variables, including temperature, pH, residence time, and substrate concentration, along with kinetic parameters from the Modified Gompertz equation characterizing each substrate. The BO algorithm was employed to optimize the ANN architecture, and 5-fold cross-validation was used to evaluate model generalization ability. The proposed hybrid model achieved outstanding predictive performance (R² = 0.9980, RMSE = 0.0117, MAE = 0.0062), confirming its accuracy and robustness. Furthermore, SHAP analysis and correlation metrics provided interpretable insights into feature contributions, particularly the relevance of kinetic descriptors. Overall, the proposed BO–ANN framework offers a scalable, interpretable, and biologically grounded tool to improve predictive accuracy and support the design of more efficient and sustainable biohydrogen production systems
Early lactate elimination trend during therapeutic hypothermia predicts acute kidney injury in hypoxic ischemic encephalopathy
No full textBackground: Acute kidney injury (AKI) is an important complication in neonates with hypoxic ischemic encephalopathy (HIE). The aim was to assess the association between early lactate elimination trend and development of AKI in neonates with HIE receiving therapeutic hypothermia. Methods: Medical records of 257 neonates with moderate-severe HIE were retrospectively analyzed for development of AKI based on neonatal Kidney Disease Improving Global Outcomes (KDIGO) criteria. Blood lactate values over time for the first 5 days were recorded. The percentage decrease in lactate values was calculated during the first 12 h and on a daily basis and reported as lactate elimination trend. Logistic regression analysis and receiver operating characteristics curve (ROC) analysis were conducted. Results: AKI developed in 70 neonates (27.2%). Median initial and 12-h lactate values were significantly higher in the AKI group. Lactate elimination trend at 12-h was significantly lower in the AKI group compared to neonates with no AKI (43.6% vs 61.4%, p < 0.001). Lower 12-h lactate elimination trend was associated with development of AKI (OR: 21.27, 95%CI: 6.73–67.17, p < 0.001). ROC curve analysis demonstrated a 47.5% decrease in lactate values at 12-h as critical cut-off value of lactate elimination trend with 90% specificity and 64% sensitivity to predict AKI. Area under curve was found to be 0.813 (95% CI: 0.76–0.86, p < 0.001). Conclusions: Lactate elimination trend in the first 12 h can be used as an early marker for AKI in neonates with HIE receiving therapeutic hypothermia. The presence of decreased lactate elimination trend will allow for careful fluid management and early medical interventions in this highly vulnerable patient population
KOCAELİ BÖLGESİNDE BULUNAN ÜNİVERSİTE ÖĞRENCİLERİNİN SIFIR ATIK BİLİNCİNİN VERİ MADENCİLİĞİ YÖNTEMLERİ İLE ANALİZİ
No full textGünümüzde artan çevresel sorunlar karşısında sürdürülebilir çözümler geliştirmek, özellikle genç nesillerin katılımıyla mümkündür. Bu bağlamda Kocaeli bölgesindeki üniversite öğrencilerinin sıfır atık bilincini ölçmeye ilişkin araştırma, 428 öğrencinin katılımıyla gerçekleştirilen anket verilerini analiz ederek, toplumsal cinsiyet ve eğitim düzeyinin çevre bilinci üzerindeki etkilerini ortaya koymuştur. Kadın öğrencilerin erkeklere göre daha duyarlı ve bilinçli davranışlar sergilemesi, üst sınıf öğrencilerinin gösterdiği olumlu performans ise çevre bilinci açısından farklılıkları ortaya koymuştur. Veri madenciliği teknikleriyle yapılan analizler ise, bilgi düzeyi ve günlük alışkanlıkların (plastik kullanımı, atık ayrıştırma gibi) davranış değişikliğinde kilit rol oynadığını göstermiştir. Özellikle orta düzeyde bilgi sahibi olan öğrencilerin en tutarlı davranışları sergilemesi, aşırı bilgi yükünün değil, dengeli bir farkındalığın etkili olduğunu ortaya koymaktadır.Bu bulgular ışığında, üniversitelerde çevre eğitimlerinin pratik uygulamalarla desteklenmesi, kampüs altyapısının iyileştirilmesi ve hedef gruplara özel iletişim stratejileri geliştirilmesi gerektiği sonucuna varılmıştır. Araştırma, gençlerin sürdürülebilir bir gelecek inşasındaki rolünü vurgulayarak, politika yapıcılar ve eğitimciler için yol haritası niteliği taşımaktadır.</jats:p
Enhanced Ti/TiO2-RuO2-SnO2 anode material for a sequential electrocoagulation-electrooxidation treatment of real Teflon plating industrial wastewater
No full textRapid expansion of the Teflon industry has intensified the release fluoropolymer-laden effluents, rich in polytetrafluoroethylene (PTFE) contaminants and precursors to per - and polyfluoroalkyl substances (PFAS). Conventional treatment methods struggle to degrade these persistent pollutants due to their chemical inertness and stability. This study presents a detailed and reproducible sequential electrocoagulation (EC) and electrooxidation (EO) approach for treating real Teflon plating process wastewater (TPWW). EC using Al electrodes at optimized conditions (5 mA/cm2, pH 6, 10 mins) achieved significant removal of turbidity, suspended solids, and chemical oxygen demand (COD) with minimal sludge and energy costs. Subsequent EO treatment with a Ti/TiO2-RuO2-SnO2 anode at optimal conditions (pH 3, 30 mA/cm2, 90 mins) demonstrated over 99% COD and 92% TOC removal efficiencies. The sequential EC–EO process demonstrated effective pollutant removal, energy efficiency, and operational scalability. This mechanistically grounded approach offers a reproducible, cost-effective solution for treating fluoropolymer-laden industrial effluents, contributing to research efforts towards enhancing water treatment efficiencies. The findings contribute to sustainable water management by advancing scalable electrochemical protocols for PFAS-related effluents, directly supporting UN Sustainable Development Goal 6 targets on water quality improvement, integrated resource management, and ecosystem protection
We Are Left Alone: Challenges of Data Use in Schools With Regard to Data-Based Decision-Making Steps
No full textData-driven decision-making has become increasingly important for improving school processes and strengthening instruc-tional and managerial practices. Despite the growing emphasis on data use in education, little is known about how schools andteachers operationalise data in their daily decision-making processes. This study examined the implementation of data-drivendecision-making at both the school and classroom levels, as well as the associated challenges. The study involved 12 teachers and13 school principals in Turkey, selected through snowball sampling, and collected data through semi-structured interviews, an-alysed using content analysis. The study reveals that school participants struggle with data analysis due to time constraints, lackof data literacy skills, and lack of stakeholder support. The research recommends coordination with senior management unitsand stakeholder cooperation to acquire necessary knowledge and skills for data use, emphasising the importance of effectivedata managemen</p
Comparative Analysis of Radial and Tangential Diffuser Centrifugal Pumps, at Varying Specific Speeds
No full textIn this study, three centrifugal pumps, with specific speeds - dimensionless parameters used to assess pump performance - of 19, 27 and 42, were numerically investigated to evaluate the influence of diffuser type on radial-flow pump performance. For each specific speed, the radial and tangential diffuser configurations were paired with identical impeller geometry, ensuring a one-to-one comparison at the same head (20 m) and rotational speed (2800 rpm). The specific speeds correspond to flow rates of 250, 500, and 1200 L/min, respectively. The results show that low specific speeds exhibit greater unsteadiness, with head fluctuations decreasing from approximately 4 m at n(q) : 19 to approximately 0.5 m at n(q) : 42. At low specific speeds, the radial diffuser generates a higher head due to reduced flow separation; however, as specific speed increases, the tangential diffuser produces a higher head, consistent with its ability to accommodate stronger tangential momentum. Although the radial diffuser displays slightly larger instantaneous head fluctuations at n(q) : 27 and 42, it experiences lower hydrodynamic force levels than the tangential diffuser at the same operating conditions. This distinction highlights that head fluctuation and surface-integrated force response are governed by different mechanisms. The systematic comparison across three specific speeds provides new insight into diffuser selection, demonstrating that appropriate diffuser geometry enhances hydraulic efficiency, suppresses unsteady flow structures, and reduces loading on volute surfaces. These findings provide practical guidance for the design of diffusers in centrifugal pumps
KOCAELİ ÜNİVERSİTESİ HASTANESİNDE DİYALİZ TEDAVİSİ ALAN TİP 2 DİYABETES MELLİTUSLU HASTALARIN DİYABET İLE İLGİLİ DENEYİMLERİ; BÜTÜNCÜL YAKLAŞIM VE AİLE HEKİMİNİN ROLÜNE İLİŞKİN HASTA PERSPEKTİFİNİN NİTEL ÇALIŞMASI
No full textEndoplasmic reticulum-localized TurboID-mediated labelling reveals distinct secretome profiles of MCF-10A and MDA-MB-231 cells
No full textBreast cancer is one of the most prevalent cancers and the leading causes of cancer-related deaths. The lack of reliable biomarkers for accurate subtyping and early diagnosis continues to hinder early detection and treatment. Secretome proteins represent an accessible and valuable source of biomarkers due to their roles in cell communication, signalling and shaping the extracellular microenvironment. In this study, secretome proteins from two cell lines, MCF-10A and MDA-MB-231, representing healthy and aggressive breast cells, respectively, were labelled with ER-localized TurboID-mediated enzymatic biotinylation approach at the endoplasmic reticulum. The biotinylated samples were enriched using streptavidin-coated magnetic beads and analysed by label-free quantitation using nHPLC LC-MS/MS. The regulated proteins were subjected to bioinformatics analyses using STRING and g:Profiler tools to identify candidate biomarkers. Proteomic analysis identified 206 proteins, with approximately 82% belonged to secretome proteins. Among them, 65 were differentially regulated which were associated with hydrolytic activity, cell adhesion, and lipid metabolism. CST1, APOC1, and POSTN had previously been associated with cancer, while TEX10, LZIC, and PSMA3 were implicated in breast cancer for the first time. Our findings demonstrates extensive secretome remodelling in invasive breast cancer cells, unveiling potential secreted biomarker candidates that may improve breast cancer diagnosis and treatment strategies.</p