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The application of deep learning techniques in the medical field, specifically for Atrial Fibrillation (AFib) detection through Electrocardiogram (ECG) signals, has witnessed significant interest. Accurate and timely diagnosis increases the patient's chances of recovery. However, issues like overfitting and inconsistent accuracy across datasets remain challenges. In a quest to address these challenges, a study presents two prominent deep learning architectures, ResNet-50 andDenseNet-121, to evaluate their effectiveness in AFib detection. The aim was to create a robust detection mechanism that consistently performs well. Metrics such as loss, accuracy, precision, sensitivity, and Area Under the Curve (AUC) were utilized for evaluation. The findings revealed that ResNet-50 surpassed DenseNet-121 in all evaluated categories. It demonstrated lower loss rate 0.0315 and 0.0305 superior accuracy of 98.77% and 98.88%, precision of 98.78% and 98.89% and sensitivity of 98.76% and 98.86% for training and validation, hinting at its advanced capability for AFib detection. These insights offer a substantial contribution to the existing literature on deep learning applications for AFib detection from ECG signals. The comparative performance data assists future researchers in selecting suitable deep-learning architectures for AFib detection. Moreover, the outcomes of this study are anticipated to stimulate the development of more advanced and efficient ECG-based AFib detection methodologies, for more accurate and early detection of AFib, thereby fostering improved patient care and outcomes. [ABSTRACT FROM AUTHOR]

Harvesting solar energy for efficient photothermal conversion and steam generation over solar evaporators is particularly significant in the context of comprehensive solar utilization toward solving the global shortage of fresh water. Herein, a flexible Ni-based metal–organic framework composite (NMC) with hierarchical structures is constructed as a photothermal material for solar steam-generation devices. Besides, a phase change material (PCM)-based thermal storage pack is incorporated into the solar evaporator to overcome the solar radiation intermittency. By virtue of the synergistic effect of the promising 3D structure and excellent water transport, the NMC-PCM evaporator possesses an outstanding evaporation performance (2.55 kg m−2 h−1) under 1 sun irradiation. More strikingly, owing to the enhanced light-to-heat performance as well as large heat storage capacity, the proposed evaporator achieves a high water-evaporation rate of 1.46 kg m−2 h−1 without sunlight irradiation. This work opens up opportunities to realize excellent energy capture for solar-driven clean water production and solar thermal storage not only under sunlight incidence but also in no light environment. [ABSTRACT FROM AUTHOR]

Due to the inherent high dark current of photoelectrochemical (PEC)‐type photodetectors (PDs), there is a tricky challenge to detect weak light. In this work, high‐quality Cd0.9Pb0.1Se quantum dots (CPS QDs) are prepared by thermal injection method, with horizontal size of 6.3 nm and thickness of 3.5 nm. The CPS QDs are directly utilized to construct the working electrode of PEC‐type PDs. The effects of experimental parameters on the photo‐response behavior are systematically studied, and optimized photocurrent density of 7.1 µA cm−2 and photo‐responsivity (Rph) of 2.75 mA·W−1 are achieved. Most importantly, the obvious photocurrent signals are observed under a light power density as low as 5.6 µW cm−2. For this interesting weak light detection, apparent Rph of 6.96 mA·W−1, detectivity of 1.2 × 109 Jones, and external quantum efficiency of 2.37% are achieved. Therefore, this work not only develops CPS QDs‐based PDs but also provides an example for PEC‐type PDs in weak light detection. [ABSTRACT FROM AUTHOR]

This work explores the characteristics of two-dimensional (2D) titanium carbide (Ti3C2 MXene) and utilizes first-principles study to weigh its potential for supercapacitor applications. Scanning electron microscopy images confirm the layered morphology of the MXene, and energy-dispersive X-ray spectroscopy (EDX) analysis supports the extraction of aluminum from the MAX phase. Fourier-transform infrared (FTIR) spectroscopy confirms the presence of oxygen-based functional groups on the surface of the MXene and X-ray diffraction (XRD) patterns validate its hexagonal crystalline structure. Cyclic voltammetry (CV) analysis reveals the presence of redox peaks, indicating the pseudocapacitive behaviour of the fabricated electrode. Additionally, galvanostatic charge–discharge (GCD) measurements yield a calculated specific capacitance of 370 F g−1. Electrochemical impedance spectroscopy (EIS) substantiates the low impedance resulting from the layered structure via the adequate adsorption/desorption of cations. The utilization of first-principles density functional theory (DFT) calculations reveals the merging of conduction and valence bands, signifying effective conductivity. Both the total and partial density of states cross the Fermi level, indicating a highly efficient charge mobility process. The combination of prominent surface redox reactions and excellent conductivity contributes to the superior specific capacitance of the fabricated electrode. Overall, these results highlight the excellent electrochemical properties of the Ti3C2 MXene electrode, declaring it as a promising candidate for supercapacitor applications. [ABSTRACT FROM AUTHOR]

Recent developments in the green synthesis of metallic nanoparticles (NPs) using phytoconstituents have attracted the attention of the global scientific community. The present study was designed to synthesize silver NPs (AgNPs) using Punica granatum and Plectranthus rugosus plant extracts. The fabricated AgNPs were characterized using UV–visible spectrophotometry (UV–Vis), Fourier‐transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), and energy‐dispersive x‐ray spectroscopy (EDS). The shift in the color of the silver nitrate (AgNO3) solution after the addition of P. granatum and P. rugosus extracts indicated the synthesis of AgNPs. The effect of AgNO3 concentrations and pH on the synthesis of AgNPs was also evaluated. The findings of this study suggest that AgNO3 concentration of 1 mM, reaction time of 1 h, and pH of 7 at room temperature were the best suited conditions for the synthesis of AgNPs. According to the FTIR analysis, amidic and carbonyl compounds were primarily responsible for the encapsulation of AgNPs. SEM investigations have shown irregularly shaped geometry with sizes of 35 nm (P. granatum) and 33 nm (P. rugosus) with low agglomeration. The prepared AgNPs exhibited good potential for 2,2‐diphenyl‐1‐picrylhydrazyl radical scavenging, with values of 70% (P. granatum) and 68% (P. rugosus). Hence, we conclude that the leaves of P. granatum and P. rugosus are excellent material for designing of different plant‐extracted‐conjugated AgNPs for biomedical applications. Research Highlights: Preparation of the AgNPs using novel plants extracts.P. granatum and P. rugosus extract as reducing, capping, stabilizing, and optimizing agents.Thorough comparative characterization using UV–Vis spectrophotometer, FTIR, SEM, and EDS which is a first of its kind.Comparative antioxidant activity. [ABSTRACT FROM AUTHOR]

One of the promising approaches is solar radiation and thermal energy can be converted into electricity using photothermoelectric materials. Ceramic‐inspired photothermoelectric materials are extensively researched in the quest for efficient and sustainable energy conversion technologies. Herein, the synthesis and utilization of titanium nitride (known as tinite–ceramic) nanoparticles used first in two specific applications are reported: solar‐driven thermoelectric nanogenerators and photothermal‐based evaporation applications. The nanogenerator is innovatively fabricated via a UV‐induced deposition technique. The tinite–ceramic possesses excellent solar absorption (92.5%) and subsequent photothermally converted heat (39.9 °C) under 1 kW m−2 solar irradiation for an effective solar energy harvesting candidate. The complimentary nanogenerator endows high carrier mobility and effective photothermal‐to‐electric energy conversion (short‐circuit current, Iout = 58.8 mA) under 2 kW m−2 solar irradiation. The switchable nanogenerator maintains its reproducibility under different cycles, tailoring its tunability under different solar irradiation. More interestingly, a tinite–ceramic‐inspired solar evaporator exhibits an evaporation rate of up to 2.02 kg m−2 h−1 under 1 kW m−2 solar irradiation. Titanite's dual functionality offers the potential to revolutionize how renewable energy sources are harnessed and utilized for environmentally friendly and sustainable energy production. [ABSTRACT FROM AUTHOR]

Land use has a great impact on soil dynamics. The soils of various land use systems in Central Karakoram have been under immense pressure in the recent past due to certain anthropogenic activities such as land use practices and land use cover changes. These influences have an impact on the spatial distribution of metallic elements (MEs) in the soils of various land uses. Herein, we investigated the occurrence of the MEs, copper (Cu), zinc (Zn), and nickel (Ni), in soils of various land uses such as the permafrost, pasture, forest, and agricultural lands of the Central Karakorum region. The MEs were extracted in exchangeable, adsorbed, organically bound, carbonated, precipitated, and residual forms. The concentrations of MEs showed a significant dependence on the extraction method used, and the extraction trend followed the order of EDTA > HNO3 > KNO3 > NaOH > H2O. Zn showed the highest concentration compared to Ni and Cu in all extractions, whereas the land uses' ME concentration followed the order of agricultural land > permafrost > forest > pasturelands. The highest values of total Zn, Ni, and Cu were 712 ± 01 mg/kg, 656 ± 02 mg/kg, and 163 ± 02 mg/kg, respectively, in agricultural soil. The ME concentration showed significant variations between different land uses, and the highest concentration was noted in agricultural soil. Zn was found to be a dominant ME compared to Ni and Cu. We believe this effort will provide opportunities for scholars to investigate MEs around the globe. [ABSTRACT FROM AUTHOR]