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Antioxidant, anti-acetylcholinesterase, antimicrobial, and anticancer activities of Morin–Cu(II) hybrid Nanoflowers
No full textIn recent years, various nanostructures, including nanoflowers, have attracted attention due to their effective biomedical properties. In this study, M@hNFs were synthesized using morin as the organic component and Cu2+ ions as the inorganic component. The prepared nanoflowers were characterized by SEM, EDX, FTIR, and XRD analyses, and their biological activities were subsequently investigated, including anticancer effects against MCF-7 breast cancer cells, acetylcholinesterase (AChE) inhibitory activity, antioxidant capacity, antibacterial activity against Staphylococcus aureus, Enterococcus faecalis (E. faecalis), Pseudomonas aeruginosa, Escherichia coli, methicillin-resistant Staphylococcus aureus (MRSA), and multidrug-resistant Escherichia coli (MDR E. coli) using the broth microdilution method, as well as antibiofilm activity against MRSA and MDR E. coli. SEM analysis revealed that the synthesized M@hNFs exhibited a diameter of 24.69 μm. Antioxidant assays demonstrated IC₅₀ values of 131.3 μg/mL (DPPH) and 51.3 μg/mL (ABTS). The AChE inhibitory activity was confirmed with an IC₅₀ value of 72.2 ± 2.1 μg/mL. Furthermore, M@hNFs reduced the viability of MCF-7 cells to 56 % at 500 μg/mL. In antibacterial assays, the synthesized hNFs exhibited stronger activity compared with morin alone, showing the most potent effect against E. faecalis with a MIC value of 32 μg/mL. Importantly, the hNFs also demonstrated activity against resistant strains, inhibiting MRSA and MDR E. coli at 256 μg/mL. At 1024 μg/mL, M@Cu-hNFs inhibited biofilm formation by MRSA and MDR E. coli by 69.7 % and 66.3 %, respectively. Taken together, these findings indicate that the prepared M@hNFs possess multiple biomedical properties and hold significant potential for further studies and future biomedical applications
Data-driven fault monitoring of parallel flow thermal exchanger under wide-span operation using deep learning
No full textOperation of industrial exchangers under thermal stress and wide-span varying conditions increasingly complicates the process monitoring task. Under such circumstances, confusing effects of faults could be observed, misleading in turn the operators’ assessment. In this paper, a data-driven fault monitoring system is designed for a parallel flow thermal exchanger under consideration of wide-range operating conditions. The designed monitoring scheme consists of a data-based residual generation block, a Convolutional Neural Network (CNN)-based fault detection block and a diagnosis block, running consecutively to detect and identify faults of different types, including leakage events, temperature sensing malfunction and actuators failures. Comparable profiles of system temperatures were observed in healthy and some faulty modes, making the fault detection and diagnosis tasks rather impossible while leveraging raw sensors data. To overcome this issue, data-driven detection residuals are used together with a CNN classifier to put in evidence and identify the actual faults. The proposed monitoring scheme is tested under distinct healthy and faulty scenarios, showing superior performance over other machine learning and deep learning methods. Moreover, full satisfaction with explainable results reflecting the process physics was obtained under the critical water leakage events
A novel therapeutic approach: The effect of letrozole-assisted synchronization on reproductive performance in suckling ewes during the non-breeding season
No full textThe aim of the present study was to investigate the effect of letrozole treatment on the success of a progesterone-based synchronization protocol and fertility parameters in suckling Awassi ewes during the anoestrus period. One hundred and five multiparous, suckling Awassi ewes were used. Ewes (n = 105) were randomly divided into three groups as Control (n = 35), LET-4 (n = 35) and LET-0 (n = 35). Four days before the synchronization protocol (D-4), letrozole at a dose of 1 mg/kg was administered subcutaneously (s.c.) to the LET-4 group, while the LET-0 group received it on the day of protocol initiation (D0). The control group received 1 mL of benzyl alcohol s.c. at both time points as a placebo. Subsequently, intravaginal sponges containing 60 mg medroxyprogesterone acetate were inserted into all ewes (D0). The sponges were kept in the vagina for 7 days and 500 IU eCG and 75 mu g d-cloprostenol were administered intramuscularly on the day the sponges were removed. Blood samples were taken for measurement of serum E2, FSH and P4 before sponge insertion (D-4 and D-2), on the day of sponge insertion (D0), after sponge insertion (D2 and D4), at mating (DM) and post-mating days (DPM-7, 14, 21, 35 and 50). Pregnancy was diagnosed by transrectal ultrasonography at DPM-21, 35, and 50. The overall mean serum FSH concentrations, calculated across all sampling days, were significantly higher in the LET-4 group (27.68 f 1.56 mIU/mL) than in LET-0 (21.85 f 0.87 mIU/mL) and Control (18.54 f 0.91 mIU/ mL) (P 0.05). In conclusion, letrozole administration four days before the synchronization protocol significantly enhanced reproductive performance in suckling ewes during the non-breeding season. These results suggest that this approach could be a promising alternative strategy to improve protocol success without resorting to early weaning
Enhancing ion conductivity depending on calcination conditions for the (BiO<sub>1.5</sub>)<sub>1-x-y</sub>(ErO<sub>1.5</sub>)<sub>x</sub> (DyO<sub>1.5</sub>)<sub>y</sub> ceramic electrolytes at intermediate temperatures
No full textBi2O3, with its face-centered cubic crystal structure, has higher oxygen ion conductivity than other ceramic ion conductors at the comparable temperatures. Maintaining this phase while keeping superionic characteristics makes it a suitable electrolyte for SOFC units operating at moderate temperatures. The current research focused on the influence of calcination temperature on the crystalline structure and thermoelectric characteristics of all ceramic electrolytes. The XRD patterns prove that when the calcination temperature increases, the minor peaks indicating the mixed phase decrease, and all specimens except the (BiO1.5)(0.92)(ErO1.5)(0.04)(DyO1.5)(0.04) are stable at room temperature. The existence of endothermal peaks on the DTA curves at around 600 degrees C clearly indicates the order-disorder transition (ODT). Conductivity generally increases with an increase in the calcination temperature, and the highest conductivity is found to be 0.38 S/cm at 800 degrees C for the (BiO1.5)(0.88)(ErO1.5)(0.04)(DyO1.5)(0.08.) This value is comparable to studies that get the optimum conductivity with a double-doping technique. The FE-SEM images show the atomic aggregations and pores on the grain boundary at low-temperature calcination (<730 degrees C), but above it, they are smooth, and the grain boundary lines are straight, which indicates low boundary resistance
Ortaokul öğrencilerinin geometrik düşünme alışkanlıklarını geliştirmeye yönelik öğretim ortamının tasarlanması ve değerlendirilmesi
No full textThe relationship between feeling of burden and happiness in older adults cohabiting with their families: The serial mediating role of mental well-being and loneliness
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Neural network-based prediction of mechanical properties in high-strength fly ash-based geopolymer mortars: a comparative analysis of model architectures and optimizers
No full textThis study investigates various machine learning models, namely multi-layer perceptron (MLP) and generalized regression neural network (GRNN), for predicting the mechanical properties of high compressive strength geopolymer mortars. Both classification (MLPC and GRNNC) and regression (MLPR and GRNNC) based models, with MLP architectures comprising 1 and 2 hidden layers, are developed. Furthermore, three optimization algorithms, namely Levenberg–Marquardt (LM), momentum (M), and resilient backpropagation (R), are utilized. The models’ inputs are alkali concentrations, heat-curing temperatures, and curing periods. The results showed that the classification-based MLP with one hidden layer and resilient optimizer (MLPC-1-R) outperformed the other models by recording lower prediction deviations and high prediction accuracy. On the other hand, the regression-based models showed promising results and less sensitivity to the optimization type, unlike the classification-based ones. Finally, the resilient backpropagation (R) optimizer tends to provide consistent and high performance for both classification and regression-based models
Vortex dynamics of novel whale-biomimetic and conventional wings: Influence of aspect ratio on tip and fragmented flow structures
No full textThe interaction of the tip vortex and the fragmented vortex on novel humpback whale-biomimetic wings with different low aspect ratios and their effects on aerodynamic performance are presented in this study. A baseline NACA 0015 airfoil and a modified configuration were tested at a chord-based Reynolds number of 0.975 x 104 for different aspect ratios (AR = 1, 2, 3, and infinite). The oil flow visualisation and force measurements were used to explore the effects of the tubercle modification on flow topology, unsteady flow, stall mechanisms, and fluid-structure interactions. Moreover, time-dependent force results were served for spectrogram analysis, which was presented first in this study, to reveal flow modes occurring. The results demonstrate that the whale-inspired geometry alters the laminar separation bubble dynamics by fragmenting large coherent structures into smaller three-dimensional bubbles, which are less susceptible to tip vortex interactions. Time-resolved lift measurements and spectrogram analyses showed that the whale-inspired leading-edge fragmented laminar separation bubbles into smaller, higher-momentum structures, generating higher-frequency flow (fragmented laminar separation bubble-induced and whale flow interaction-induced) modes that mitigated coherent vortex shedding. In AR2, AR3, and 2D wings, two dominant modes emerged. This can be attributed to the intensification of leading-edge vortices interacting with the whale structure, with an increasing aspect ratio. The modified wings exhibited enhanced lift coefficient and delayed stall, particularly for higher aspect ratios, where a mild stall replaced abrupt stall in baseline wings. However, at post-stall conditions, the lift force exhibited higher fluctuation-based stability index values for the whale wings, indicating that while the modification improved overall aerodynamic performance, it slightly reduced flow stability. While studies in the literature have shown that high aspect ratio whale wings provide significant aerodynamic enhancement, particularly at high angles of attack, this study observed that this effect is accompanied by increased vibration due to small, fragmented vortices. Increased vibration is likely to lead to stability issues