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Response of the stratified flow structure and energy production to the climate change effects in a Sea Strait: the case study of the Bosphorus
No full textThe Bosphorus has a considerable energy potential due to its topography and environmental conditions. It is a non-tidal strait and characterized by a stratified flow structure, which could show high variability spatially and temporally. Therefore, unlike tidal channels, many processes and uncertainties should be considered for energy production in the Strait. In particular, the change of the driving forces in the future that determine the flow structure is a major uncertainty for energy production. This study aims to determine the energy production in the Bosphorus under the impact of climate change in the future. The extreme flow characteristics and energy production were identified considering two different climate change scenarios (RCP 2.6 and RCP 8.5). In the high-energy region of the Bosphorus, upper layer thickness projections vary from 15 m to 19 m, and Marine Current Turbines can operate 50–80 % of the year. The average annual energy production in the Bosphorus is projected to vary between 1.42 MW and 2.76 MW. Assuming that the maximum and minimum conditions will be equally distributed in the period up to 2100, an average annual energy production of ∼ 2.1 MW will be realised in the Bosphorus through the sample MCT array
Fabrication, antioxidant, and optical properties of Poly(ε-caprolactone)/metal oxide fibers by electroblowing
No full textThe properties of nanofibers (NFs), such as their aspect ratio, tensile strength, porosity, and the ability to combine organic–inorganic materials, make them important in biomedical applications, electronics, and optics. Several methods for the production of these NFs are still being developed, and electroblowing is one such method. This method allows for high yields in very short times, while also saving energy through the use of airflow. By utilizing the advantages of this method, metal oxide nanoparticle ()NFs will have the potential to be used in many applications, stimulating the production of new materials. In this study, poly(ε-caprolactone)(PCL)/MeONP NFs were produced via electroblowing using PCL obtained by deposition, along with copper oxide (CuO), iron oxide (FeOx), and manganese oxide (MnO) NPs. These fibers were characterized by FTIR, UV–Vis spectroscopy, XRD, TGA, DTG, DMA, SEM, and EDS analyses. These PCL/MeONP NFs were observed to have antioxidant properties by the 2,2′-Azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) assay, and the highest antioxidant activity of 54.32 μg TE/mg was obtained from PCL/CuO NFs. The estimated optical band gap of these nanofibers was calculated to be 2.41–2.82 eV. PCL and MeONPs are widely used as biomaterials, and the electroblown PCL/MeONP NFs presented for the first time in this study have the potential to be used as biomaterials in many biomedical applications
Tracing the molecular evolution of Foxp2 proteins in vertebrates from fish to tetrapods: Insights into poly-Q tract variation, structural changes, and interaction networks
No full textFoxp2 is a transcription factor containing poly-Q repeats, commonly found in brain proteins. It plays essential roles in speech, motor function, cognition, and emotion, and is expressed during embryonic development in the brain, lungs, heart, and intestines. Foxp2 is highly conserved among vertebrates. This study investigated the molecular evolution of Foxp2 by analyzing its sequence, structure, post-translational modifications (N-glycosylation and phosphorylation), positive selection signals, conserved motifs, domains, and interaction networks across five representative vertebrates: human, cattle, coelacanth, zebrafish, and pufferfish. Structural comparison showed closer similarity among human, cattle, and coelacanth, with a poly-Q tract absent in zebrafish and pufferfish. A unique 25-amino acid insertion was identified only in cattle. Two conserved domains were found in all species, while one domain was restricted to human, cattle, and coelacanth. Of 37 predicted motifs, motifs 30–37 associated with poly-Q repeats were exclusive to human, cattle, and coelacanth. Poly-Q tracts are notable due to their links with neurodegenerative disorders such as prion diseases and Huntington's disease. Two distinct N-glycosylation profiles emerged: one shared by human, cattle, and coelacanth, and another by zebrafish and pufferfish. Protein interaction analysis consistently identified Ctb1, Nfatc2, and Tbr1 as partners. Phylogenetic analysis placed coelacanth closer to the human/cattle clade than to teleosts, reflecting its transitional evolutionary status. Together, these integrative bioinformatics results provide new insights into the molecular evolution of Foxp2, highlighting the evolutionary position of coelacanth and the functional relevance of poly-Q repeats in vertebrates
Trace cadmium determination in tap water samples using hydrazone type ligand/diphenylcarbazone and spray-assisted droplet formation-liquid phase microextraction in SQT-FAAS system
No full textToxic metals are known pollutants to pose high toxicity to the environment and humans when they occur above threshold levels. In order to meet the requirements of environmental quality standards established by pertinent regulations, analytical processes that perform quick, accurate, and precise determination of such pollutants are becoming more and more important. This study offers a rapid, efficient, and sensitive method for cadmium determination in tap water samples by slotted quartz tube–flame atomic absorption spectrometry (SQT-FAAS). A spray-assisted droplet formation-liquid phase microextraction (SADF-LPME) method was developed to simultaneously extract and preconcentrate cadmium ions using microliter volumes of solvent in agreement with green analytical chemistry. Hydrazone type complexing ligand and diphenylcarbazone were tried to check the complex formation efficiencies. The optimum extraction conditions were determined by comprehensive examination of the parameters affecting complexation and extraction. The limit of detection/limit of quantification values for the DPC and L-4 hydrazone ligands under optimum conditions were 0.70/2.4 µg/L and 1.1/3.5 µg/L, respectively. The linear dynamic range for cadmium was found to be 2.0–75 µg/L, and the correlation coefficient (R2) was higher than 0.99. The method has been successfully applied to tap water samples, with recovery results close to 100% validating the accuracy of the method
Adaptation of the Couple Communication Satisfaction Scale to Turkish: Its Associations With Family Communication, Dyadic Trust, and Relationship Satisfaction.
No full textThis study validated the Couple Communication Satisfaction Scale (CCSS) in Türkiye through two studies with distinctsamples. Study I (N = 371, mean age = 27.56) examined factorial validity, reliability, item response theory, and measurementinvariance, confirming an 11‐item, five‐factor structure via confirmatory factor analysis with acceptable internal consistency.Study II (N = 482, mean age = 29.24) tested structural relations among family communication, dyadic trust, and relationshipsatisfaction using structural equation modeling, revealing that family communication positively predicted dyadic trust andcouple communication satisfaction, which in turn predicted higher relationship satisfaction. Overall, findings indicate that theCCSS is a valid and reliable instrument for assessing couple communication satisfaction in the Turkish cultural context.</p
Reliability assessment of markerless technologies in biomechanical motion analysis: a performance comparison
No full textMolecularly imprinted polymer-based electrochemical biosensors for medical diagnostics: Artificial intelligence perspective
No full textMolecularly imprinted polymers (MIPs) have emerged as a significant advancement in the realm of electrochemical biosensors, primarily due to their advantages in rapid, enzyme-free, precise, and cost-effective pathogen detection. The functional properties of MIPs can be tailored through the careful selection of formulation components. This review aims to examine MIP-based technologies utilized for the identification of disease biomarkers, encompassing a range of targets such as bacteria, viruses, C-reactive protein, necrosis factor-alpha, and antibodies, including Immunoglobulin G (IgG) and Immunoglobulin M (IgM). Additionally, the discussion will focus on the materials employed, such as polypyrrole, poly(o-phenylenediamine), and poly(aminophenol), while assessing the selection of monomers, templates, crosslinking agents, and modifiers that can enhance the sensing performance of MIPs. Moreover, this review will highlight the applications of MIPs across diverse pathogen categories and consider the integration of artificial intelligence into MIP-based technologies. This integration holds promise for improving diagnostic accuracy and optimizing sensor data processing. Future initiatives are expected to emphasize the development of MIP biosensors characterized by improved sensitivity, diminished detection thresholds, and the utilization of biocompatible polymers, thereby fostering advancements in monitoring applications and contributing substantially to global medical diagnostics
The Printability of PC, MgO, and Reactive MgO-based Mixtures Using Extrusion-Type 3D Printing
No full textInvestigating the Tribological Performance of Laser Powder Bed Fusion-Manufactured Maraging Steel Through Advanced Postprocessing Techniques
No full textLaser powder bed fusion (LPBF) facilitates the production of high-strength maraging steel components with intricate geometries; however, inherent surface roughness (∼6.125 μm) and suboptimal tribological performance restrict their application in wear-critical contexts. This study introduces an innovative approach that synergistically combines sandblasting and vibratory polishing to enhance surface integrity and wear behavior. Postprocessing resulted in a 54% reduction in surface roughness (Ra = 2.809 μm) and a 4.1% increase in microhardness (481 HV). Tribological evaluations under dry, machine oil (MO), and soybean oil (SO) lubrication demonstrated that vibratory polishing decreased wear by 76.5% (263.02 × 10-9 mm3/Nm) and friction by 62.6% (μ = 0.247) under dry-sliding conditions. MO lubrication on polished surfaces achieved near-hydrodynamic conditions, resulting in ultra-low wear (4.87 × 10-9 mm3/Nm) and friction (μ = 0.036). Notably, soybean oil, a sustainable bio-lubricant, exhibited performance comparable to MO (wear factor: 4.17 × 10-9 mm3/Nm), underscoring its potential for eco-tribological systems. Field emission scanning electron microscopy (FE-SEM) analysis confirmed a transition from severe abrasive wear (as-built) to mild adhesive wear (postprocessed), directly correlating surface topography with lubrication regime dominance. This research establishes vibratory polishing as a pivotal enabler for hydrodynamic lubrication in LPBF components, thereby unlocking their potential in aerospace, automotive, and precision tooling industries where wear resistance is critical for operational longevity
Enhancement of rifaximin bioavailability and antibacterial efficacy through mPEG-b-PCL micelles and chitosan-coated systems
No full textRifaximin (RFX) is a BCS Class IV antibiotic characterized by low water solubility and limited bioavailability, although it possesses broad-spectrum antibacterial activity. To overcome the limitations of RFX use, RFX was encapsulated in methoxy poly(ethylene glycol)-block-poly(ε-caprolactone) (mPEG-b-PCL) micelles within the scope of this study and subsequently coated with chitosan (CS) to improve structural stability. The micelles were synthesized via nanoprecipitation. The optimized RFX-loaded micelles (OPT-M) had an average size of 75.18 ± 0.62 nm, a polydispersity index (PDI) of 0.08 ± 0.014, and an encapsulation efficiency of 85.19 ± 2.76 %. The CS-coated micelles (OPT-C-M) exhibited an increase in size to 213.95 ± 6.26 nm, a PDI of 0.250 ± 0.002, and a zeta potential shift to +28.4 ± 2.46 mV. Morphological analyses confirmed the spherical shape of the micelles, and colloidal stability studies verified the enhanced stability. Both formulations significantly enhanced the antioxidant activity compared to free RFX. Antibacterial studies indicated substantial reductions in minimum inhibitory concentration (MIC) values against S. aureus and E. coli. OPT-M and OPT-C-M showed 8-fold and 4-fold MIC reductions for S. aureus, and 4-fold and 8-fold MIC reductions for E. coli, respectively. Furthermore, both formulations maintained high biocompatibility, exceeding 70 % viability in L929 fibroblast cells at effective concentrations. These findings highlight the potential of CS-coated micelles to enhance RFX's therapeutic efficacy, demonstrating promise for advanced antibiotic delivery applications