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Impedimetric detection of carcinoembryonic antigen using a pencil-graphite electrode integrated into a 3D-Printed electrochemical cell
No full textIn the present work, we present a 3D-printed mini electrochemical cell designed using polylactic acid (PLA) filament. This platform incorporates a fully integrated electrochemical cell, where the working, reference, and counter electrodes are entirely fabricated from pencil graphite electrodes (PGE). A Reference electrode for the three-electrode system was obtained by applying conductive silver ink onto a pencil graphite electrode. In this study, an electrochemical immunosensor was developed for the detection of carcinoembryonic antigen (CEA). The sensor surface was functionalized using appropriate chemical agents, followed by the immobilization of Anti-CEA for specific recognition. CEA determination was performed by monitoring the interactions on the sensor surface with the Electrochemical Impedance Spectroscopy (EIS). Combined with a 3D-printed electrochemical cell, the CEA immunosensor exhibited a linear response to CEA from 4.0 ng mL- 1 to 250 ng mL- 1 with a detection limit (LOD) of 1.2 ng mL- 1. Also, the proposed immunosensor was successfully applied for CEA detection in commercial human urine samples, achieving CEA detection recoveries ranging from 93 % to 98 %. The developed electrochemical biosensor shows promise for accurately detecting CEA in real samples, providing a precise method that could be valuable for clinical tumor detection
ANN vs. MARS modeling: Experimental performance enhancement of MgO-TiO<sub>2</sub>/water binary and TiO<sub>2</sub>/water mono nanofluids in a plate-fin heat exchanger
No full textThis study has experimentally examined the cooling performance/heat transfer rate, effectiveness, and UA product of a PFHE (plate-fin heat exchanger) used on a motorcycle, employing MgO-TiO2/water binary and TiO2/water mono nanofluids, in addition to pure water, at various concentrations (0 %, 0.00645 %, 0.0125 %, 0.025 % and 0.05 %), inlet temperatures (70 degrees C and 80 degrees C), and flow rates (6.5 LPM, 9.5 LPM and 12.5 LPM). The maximum heat transfer rate, effectiveness, and UA product values observed were 673.868 W, 0.856, and 27.768, respectively, with a 0.025 % concentration of MgO-TiO2/water binary nanofluid at an inlet temperature of 80 degrees C and a flow rate of 6.5 LPM. The heat transfer rate, effectiveness, and UA product values for pure water (0 %) under the same conditions were 591.152 W, 0.809, and 23.534, respectively. By applying the acquired data, both ANN and MARS were employed to predict effectiveness, and a comparison was established between the two methods. According to the best result for ANN (Tin = 80 degrees C and MgO-TiO2/water), the MARS result indicates an MSE of 1.17 x 10-5, RMSE of 0.0034, SSE of 0.0002, MAPE of 0.3411, and an R2 of 0.9921. By comparison, the ANN results indicate an MSE of 2.52 x 10-6, RMSE of 0.0016, SSE of 3.78 x 10-5, MAPE of 0.0876, and an R2 of 0.9983. According to the best result for MARS (Tin = 80 degrees C and TiO2/water), the ANN result shows an MSE of 6.03 x 10-5, RMSE of 0.0025, SSE of 9.05 x 10-5, MAPE of 0.1359, and an R2 of 0.9961. On the other hand, the MARS results exhibit a MSE of 3.97 x 10-6, RMSE of 0.0020, SSE of 5.96 x 10-5, MAPE of 0.2003, and an R2 of 0.9974
H<sub>2</sub> production from H<sub>2</sub>S over activated carbon prepared at different carbonization temperatures as efficient microwave catalyst
No full textThis study aims to prepare activated carbon (AC) using sawdust as a stable and active microwave catalyst for H2 production from H2S. The AC, including mesoporous, was prepared at different carbonization temperatures (AC1:800 degrees C, AC2:900 degrees C, AC3:1000 degrees C). AC3 exhibited the highest sp2/sp3 ratio, tc-tc* transitions and mesoporosity, facilitating efficient microwave interaction and resulting in more irradiation absorption. High and similar H2 production rates using AC1, AC2, and AC3 in the microwave-heated reactor (MWHR) were obtained at different reaction temperatures. The H2 production rate obtained with AC3 at average reaction temperatures of 700 degrees C, 800 degrees C, and 900 degrees C are 13, 14, and 18 mmolx10-3/min, respectively. However, the carbonization temperature played a crucial role in H2 production per the microwave energy absorption of catalysts in MWHR. This situation can be attributed to the formation of a high sp2/sp3 ratio and more tc-tc* transitions, which enhance microwave interaction. In the long-term activity test conducted with AC3 in MWHR, stable and efficient H2 production was achieved with 14 mmolx10-3/min at an average reaction temperature of. 726 degrees C for 530 min. AC3, with superior catalytic performance, is a promising candidate for H2 production via microwave-assisted H2S decomposition
Could GSTP1, PTEN and NKX3.1 Gene Expression Be Novel Markers in the relationship between prostate cancer and epigenetics?
No full textThe effects of simulated gastric acid on the mechanical, optical, and physicochemical properties of different esthetic CAD-CAM materials
No full textA hybrid fuzzy-CNN model with feature extraction from MACD-based trends for stock market movement forecasting
No full textFinancial time series forecasting is a crucial but challenging undertaking that is necessary for creating successful strategies. Reliable forecasting systems are vital for effective investment management and algorithmic trading. This necessity drives extensive research into methods for machine learning and statistics. In the literature, numerous studies have focused on predicting price direction in stock time series, with most aiming to forecast the price direction on the same day or the following day. However, there are relatively few studies that approach this prediction by segmenting the time series into smaller parts, and the application of fuzzy sets in this context remains largely unexplored. This study presents a new method for predicting the next day's price direction, distinguishing it from previous research approaches. The approach involves identifying local trends in time series data, extracting features from these trends, converting these features into fuzzy values, and then prediction by using a deep learning method. The 40 stocks listed on BIST (Borsa Istanbul) and their daily closing values are included in the study over a ten-year period. The proposed method predicted the next day price direction as the average of 40 stocks with 79.04% accuracy score
Advanced surface modification of CoCr alloys for biomedical Applications: The impact of TiB2 and BN coatings on wear, hardness, and radiation shielding
No full textThis research looks into how Boron Nitride (BN) and Titanium Diboride (TiB2) coatings change the surface properties of biomedical CoCr alloys made with selective laser melting (SLM) technology. SEM analyses confirmed uniform coating thicknesses compatible with theoretical calculations. Radiation attenuation tests demonstrated increased linear attenuation coefficients (LAC) and mass attenuation coefficients (MAC) at 1.173 MeV for both coatings, with TiB2 providing superior performance. Mechanical tests revealed significant improvements in hardness, with TiB2 and BN increasing it by 16.2 % and 15.9 %, respectively. Wear tests showed that BN coatings reduced friction coefficients, while TiB2 increased wear resistance. HVL, TVL, and MFP parameters showed improved gamma shielding at 1.173 MeV, though less effectiveness at 1.332 MeV. These results indicate that BN and TiB2 coatings enhance the mechanical, wear, and radiation attenuation properties of CoCr alloys, making them suitable for long-lasting biomedical implants
Photophysical properties and color-tunability of diaryl ether-bridged pyrrolo[3,2-b]pyrrole (TAPP) derivatives
No full textDiaryl ether-bridged pyrrolo[3,2-b]pyrrole (DHPP) derivatives were synthesized, and their photophysical properties were systematically investigated in both solution and solid states. UV–vis spectroscopy in toluene, THF, and DMSO revealed characteristic π→π∗ absorption bands around 350–360 nm for all compounds, showing minimal solvent dependence. Fluorescence measurements indicated emissions around 430 nm in nonpolar and moderately polar solvents (toluene, THF), whereas highly polar DMSO induced pronounced bathochromic shifts (470–500 nm) for ortho-chlorinated derivatives (2-Cl (6), 2,4-diCl (10), and 2,5-diCl (11)). These shifts are attributed to enhanced stabilization of the intramolecular charge transfer (ICT) state due to increased excited-state dipole moments and specific solvation effects in DMSO. Solid-state photoluminescence (PL) studies showed ∼25 nm red shifts for the same derivatives, while other derivatives-maintained emissions near 450 nm, highlighting the effect of substituent position on excited-state conformation and electron density. CIE color coordinate analysis confirmed solvent- and substituent-dependent emission tunability, indicating potential applications as solid-state, color-tunable luminescent materials. Overall, the results demonstrate the crucial role of the diaryl ether bridge in modulating electronic communication and controlling aggregation-induced quenching, as well as the impact of substituent positioning on fine-tuning photophysical properties for advanced optoelectronic applications
