Square wave voltammetry, cyclic voltammetry, chronocoulometry, and electrochemical impedance spectroscopy were employed to assess ascorbic acid_s electrochemical behavior in multiwalled carbon nanotubes (MWCNTs)/carbon paste electrode (CPE) modified by 1-phenyl-3-methyl-4-metafluorobenzoyl-5-pyrazolone (HPMmFBP). The ascorbic acid_s irreversible oxidation peak appeared at approximately 0.5 V. The shifting of the peak potential at the pH range of 6.0_8.4 showed the involvement of protons in the ascorbic acid oxidation. Moreover, the shifting of the peak potential with scan rate in the range of 0.07_0.4 V/s confirmed that the oxidation reaction was irreversible. Under optimized conditions, the oxidative peak current showed linear dependence on the ascorbic acid_s concentration between 1 and 1000 _M with limit of detection (LOD) and quantification (LOQ) at 0.1 and 0.34 _M, respectively. HPMmFBP/MWCNT/CPE exhibit good antiinterference ability, reproducibility, repeatability, and stability .....

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Over a decade, the Malaysia National Poison Centre found that 40% of pesticide poisoning cases may be linked to excessive paraquat (PQ) in water, soil, or food, underscoring the widespread impact on public health and emphasising the importance of detecting even trace amounts of PQ residues in the environment. Thus, this study presents a novel electrochemical sensor based on multiwalled carbon nanotubes (MWCNTs) reinforced cadmium sulphide co-anchoring on graphitic carbon nitride (CdS/g-C3N4) nanocomposites for PQ detection. The CdS/g-C3N4 nanocomposite was successfully synthesised and characterised through FTIR, XRD, EDX, FESEM and TEM analysis. The modified electrode (CdS/g-C3N4/MWCNTs PE) exhibited improved electrocatalytic activity, as demonstrated by cyclic voltammetry (CV) and impedance spectroscopy. The CdS/g-C3N4/MWCNTs PE displayed a high CV peak and low Rct value which corresponded to a higher electron transfer rate, reduced charge transfer resistance and enhanced mass transpo.....

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This study was designed to investigate the chemical composition of the essential oil of Syzygium variolosum (King) Chantar. & J.Parn. and their cytotoxicity, acetylcholinesterase, antityrosinase, and anti-inflammatory activities. In total, 32 chemical components were identified in the essential oil, which made up 98.9%. The essential oil is mainly composed of _-elemene (20.2%), bicyclogermacrene (13.5%), viridiflorol (11.1%), globulol (8.6%), and selin-11-en-4_-ol (5.3%). Acetylcholinesterase, antityrosinase, and anti-inflammatory activities were evaluated with the Ellman method, mushroom tyrosinase, and lipoxygenase enzymes, respectively, while cytotoxicity was assessed using an MTT assay. The results showed that essential oil gave significant percentage inhibition (I%: acetylcholinesterase 35.2%, antityrosinase 42.5%, lipoxygenase 48.6%). Furthermore, the essential oil exhibited cytotoxicity against three cancer cell lines, HepG2, MCF7, and A549, with IC50 values ranging from 90.2 to.....

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Summary: In this present work, a sensitive electrocatalytic modified electrode based on 1-phenyl-3-methyl-4-benzoyl-5-pyrazolone (PMBP)/multiwalled carbon nanotubes (MWCNT) modified carbon paste electrode (CPE) was successfully developed. Electrochemical impedance spectroscopy, square wave voltammetry, chronocoulometry and cyclic voltammetry were used in prompt to evaluate the PMBP/MWCNT/CPE electrochemical capacity in detecting acetaminophen (APAP) in 0.1 M PBS pH 6.4. Under optimized conditions, PMBP/MWCNT/CPE displayed a well-defined electrocatalytic activity towards APAP oxidation in the linear responses which range from 1 _M to 1 mM (R2 = 0.991) with the LOD obtained at 0.245 _M while LOQ 0.816 _M. The presence of excess (10-fold and 25-fold) interferents such as sucrose, fructose, glucose, sodium chloride, sodium sulphate, potassium nitrate, lysine, potassium chloride and magnesium chloride as interferents was insignificant. The results presented in this study provide new perspec.....

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Physical fitness has long been shown to be crucial for athletes due to its contribution to decrease injury and health risks. In sport, physical fitness is important to increase athletes_ ability to perform technical movement and follow coaches_ tactical plan in the game. This study aims to investigate the anthropometric, physiological, and match-play performance of netball players and examine the relationship between physical fitness and game characteristics among netball players. Material and Methods: A total of ninety-one female netball players (mean _SD: age 18.78 _5.41 years, height 1.60 _0.01 m, and weight 56.13 _ 6.40 kg) participated in this study. Participants underwent standard anthropometry measurement (height, weight, and body mass index) and physical fitness evaluation (standing long jump, 20-meter sprint, agility T-test, sit and reach test, and multistage fitness test). Results: The findings of anthropometric and physical fitness showed that qualified players had significa.....

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This study examines the asymmetric effect of shadow economy on environmental pollution in Egypt during the 1970 and 2022 period. Using the bootstrap nonlinear autoregressive distributed lag (NARDL) bounds-testing approach, the study presents evidence of nonlinear cointegrating relationship between environmental degradation (carbon emission) and shadow economic activities (alongside globalisation, urbanisation, GDP per capita, and industrial growth). In addition, the results demonstrate that the impact of shadow economy (SE) on environmental pollution (ENV) is nonlinear, with the positive shock in shadow economy promoting environmental degradation and negative shocks promoting environmental quality, both in the short-and long-run. However, the study discovered that the magnitude of the impact of the SE on ENV is larger in the short-run. This is further validated by the dynamic ARDL simulation technique which demonstrates that the immediate effect of the SE on ENV is large. Additionally,.....

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Augmented Reality (AR) has emerged in our educational paradigm as a new tool to accelerate change in the teaching and learning process. This technology can improve students_ visualisation skills, which helps them understand abstract concepts, especially in Chemistry. Furthermore, visualisation skills help improve students_ critical thinking. This study was conducted with 16 secondary students. Before and after the intervention, students were required to complete a Purdue Spatial Visualisation Test to measure their visualisation skills. During four weeks of intervention, students explored the content using a mobile augmented reality application for learning chemical bonds (called CBOND) and completed critical thinking tasks each week. This study employed data mining using a decision tree to predict the path to improving students_ visualisation and critical thinking skills in learning chemical bonds. The results revealed that CBOND had a significant effect on students_ visualisation and .....

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