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Horseradish peroxidase (HRP), a natural enzyme, consists of a FeIII ion, which plays the role as an active center of the enzyme, wherein the binding of H2O2 to the FeIII ion creates an octahedral configuration around FeIII, leading to the decomposition of the –O–O– bond of H2O2. Based on this considering, here, we propose amorphous-carbon-functionalized Fe3O4 nanoparticles (Fe3O4@C) that serve as a peroxidase nanozyme with FeIII and exhibits peroxidase-like catalytic activity. In this work, Fe3O4@C was synthesized via a simple hydrothermal process from a suspension of Fe3O4 nanoparticles and glucose solution. The peroxidase-mimicking activity of Fe3O4@C was demonstrated following the Michaelis–Menten and Lineweaver–Burk equations of the enzymatic model. At optimized conditions, Fe3O4@C showed stronger catalytic activity than HRP, with Michaelis–Menten constants (Km) 0.052 mM and 0.004 mM for the H2O2 substrate and TMB co-substrate, respectively. Using Fe3O4@C as a replacement for HRP, a colorimetric chemical sensor for H2O2 sensing and a colorimetric biosensor for glucose detection were constructed, and they exhibited high selectivity and sensitivity with an LOD of 20 μM for H2O2 and 40 μM for glucose. The applicability of the glucose biosensor was also tested in real samples, including a 5% intravenous glucose solution and human blood serum, revealing high recovery rates. [ABSTRACT FROM AUTHOR]

This study conducts a rigorous comparative analysis between two cutting-edge instance segmentation methods, Mask R-CNN and YOLOv8, focusing on stomata pore analysis. A novel dataset specifically tailored for stomata pore instance segmentation, named PhenomicsStomata, was introduced. This dataset posed challenges such as low resolution and image imperfections, prompting the application of advanced preprocessing techniques, including image enhancement using the Lucy-Richardson Algorithm. The models underwent comprehensive evaluation, considering accuracy, precision, and recall as key parameters. Notably, YOLOv8 demonstrated superior performance over Mask R-CNN, particularly in accurately calculating stomata pore dimensions. Beyond this comparative study, the implications of our findings extend across diverse biological research, providing a robust foundation for advancing our understanding of plant physiology. Furthermore, the preprocessing enhancements offer valuable insights for refining image analysis techniques, showcasing the potential for broader applications in scientific domains. This research marks a significant stride in unraveling the complexities of plant structures, offering both theoretical insights and practical applications in scientific research. [ABSTRACT FROM AUTHOR]

The present study evaluates the performance of fiber-reinforced geopolymer, especially its flexural strength, using a Deep Learning (DL) approach, Deep Residual Network (ResNet), and the experimental work is presented. A total of 245 mixtures were employed to generate the data for the ResNet training and validating procedures. In the proposed model, the Fly Ash (FA) content, sodium silicate solution/solid binder ratio, curing temperature, curing time, fiber volume fraction, fiber length (l) and diameter (d), as well as fiber tensile strength, were considered as input factors. In contrast, flexural strength was the output parameter. The effectiveness of ResNet was evaluated by three statistical factors, correlation coefficient (R²), Root Mean Square Error (RMSE), and Mean Absolute Percentage Error (MAPE). ResNet validation revealed the effectiveness of predictive methods with 94.5%, 0.292 MPa, and 4.068% for R², RMSE, and MAPE, respectively. The suggested models may be used as standard mixtures for geopolymer concrete reinforced with steel fibers. [ABSTRACT FROM AUTHOR]

This study experimentally investigated the behavior of reinforced recycled aggregate concrete (RAC) beams under monotonic and cyclic loadings to identify the advantages and shortcomings of RAC in reinforced concrete beams. Five RAC specimens and one normal aggregate concrete (NAC) specimen were tested to failure. The concrete compositions of RAC and NAC were similar; however, the coarse aggregate of RAC was recycled coarse aggregate, while that of NAC was normal stone coarse aggregate. Results indicated similarities in the failure modes of RAC and NAC beams. Compared with NAC beams, the yield and ultimate load-carrying capacities of RAC beams were only 2.6% and 8.9% lower, respectively. The cyclic loading effect negligibly induced strength degradation but decreased ductility by 9.1%. However, the yield deflection and yield stiffness of RAC beams were 22.9% higher and 30% lower than those of NAC beams, revealing their shortcomings. The above results emphasized the potential use of RAC in structural members by addressing the high deformation characteristic of RAC (e.g., modifying the concrete composition to increase the compressive strength of RAC). The nonlinear analytical method of NAC beams, in which the fiber model and the finite element method were finally combined, can be used for RAC beam analysis with acceptable accuracy. [ABSTRACT FROM AUTHOR]

The wake transitions of the flow past two side-by-side elliptical cylinders were numerically investigated using the lattice Boltzmann method at Reynolds numbers (Re) of 40, 100, and 150, with various spacing ratios (L / D , where L represents the distance between the cylinder centers and D is their diameter) and aspect ratios (AR). This study elucidated the effects of Re, AR, and L / D on the flow characteristics, including wake structures, hydrodynamic coefficients, Strouhal number (St), and the spectral energy of the flow exerted on both cylinders. Six distinct flow patterns are observed in the A R − L / D space, such as steady shear layers, anti-phase synchronized streets, in-phase synchronized streets, single bluff body, flip-flopping, and chaotic flow. These patterns were characterized through detailed analyses, including vorticity contour plots, time histories of drag and lift coefficients, power spectral density, and proper orthogonal decomposition of vorticity fluctuations into deterministic spatial structures. Additionally, flow pattern maps and diagrams of the time-averaged pressure coefficients on the surface of the cylinders were provided to assess the influence of Re, AR, and L / D on the flow behavior. The hydrodynamic coefficients of both cylinders showed near-identical trends with significant variations depending on L / D and AR. When AR is small, the time-averaged drag coefficient and the root-mean-squared lift coefficient of both cylinders are found to be substantially higher than those of an isolated elliptical cylinder. Furthermore, a notable increase in the time-averaged lift coefficient was observed when L / D was small, attributed to the repulsive forces between the cylinders. At higher Reynolds numbers (R e = 100 & 150), substantial differences in St emerge, particularly for smaller AR values, despite the cylinders being in a side-by-side configuration. [ABSTRACT FROM AUTHOR]

Objective: This study aims to investigate the chemical constituents and biological properties of the essential oil derived from Psychotria laui, a plant recognized for its medicinal applications, particularly in traditional Vietnamese medicine, where it is utilized for the treatment of digestive and inflammatory disorders. Methods: Fresh leaves of Psychotria laui were gathered in Quangtri, Vietnam, and subjected to hydro-distillation using a Clevenger-type apparatus to obtain the essential oil. The chemical composition of the essential oil was analyzed by gas chromatography-mass spectrometry (GC-MS). The antioxidant potential was measured using the DPPH (2,2-Diphenyl-1-picrylhydrazyl) assay, while the inhibition of nitric oxide production was tested in lipopolysaccharide-stimulated RAW264.7 cells. Cytotoxicity against the SK-LU-1 cell line (human lung adenocarcinoma) was evaluated using the sulforhodamine B (SRB) assay. Results: The essential oil from Psychotria laui contained 78 distinct constituents. The major compounds identified were spathulenol (10.4%), thujopsan-2- α -ol (9.5%), 7- epi - α -eudesmol (6.5%), 14-hydroxy-9- epi -(E)-caryophyllene (4.4%), epi - α -cadinol (3.9%), α -muurolol (3.8%), 1- epi -cubenol (3.5%), and δ -cadinene (3.2%). The essential oil showed no antioxidant activity, with an IC50 (half-maximal inhibitory concentration) value greater than 500 µg/mL, in contrast to the positive control, L-ascorbic acid, which had an IC50 of 7.78 ± 0.39 µg/mL in the DPPH assay. However, its anti-inflammatory activity was evident by its ability to inhibit nitric oxide production, with an IC50 of 19.48 ± 1.53 µg/mL in lipopolysaccharide-stimulated RAW264.7 macrophages. Moreover, the essential oil exhibited potent cytotoxicity against the SK-LU-1 cancer cell line, with an IC50 of 8.49 ± 0.73 µg/mL in the SRB assay. Conclusion: The essential oil from Psychotria laui leaves contains numerous bioactive compounds and exhibits significant anti-inflammatory and cytotoxic properties, although it lacks antioxidant activity. [ABSTRACT FROM AUTHOR]

A flexible, ultrasensitive, and practical SERS chip is presented based on a paper/f-TiO2/Ag structure. The chip enhances the self-assembly of Ag nanoparticles on a cellulose fiber matrix, facilitated by smart functionalized TiO2 nanomaterials (f-TiO2). This design enables superior detection of the hazardous pesticide tricyclazole (TCZ) on crops using an advanced, simple, and efficient analytical method. Despite its straightforward fabrication process via a solvent immersion method, the intrinsic smart surface properties of the TiO2 bridging material - both hydrophilic and hydrophobic - enable the uniform and dense self-assembly of hydrophilic Ag nanoparticles (NPs) on the cellulose fiber paper substrate. This innovative design provides superior sensing efficiency for TCZ molecules with a detection limit reaching 2.1 × 10−9 M, a remarkable improvement compared to Paper/Ag substrates lacking f-TiO2 nanomaterials, which register at 10−5 M. This flexible SERS substrate also exhibits very high reliability as indicated by its excellent reproducibility and repeatability with relative standard deviations (RSD) of only 5.93% and 4.73%, respectively. Characterized by flexibility and a water-attractive yet non-soluble surface, the flexible Paper/f-TiO2/Ag chips offer the convenience of direct immersion into the analytical sample, facilitating seamless target molecule collection while circumventing interference signals. Termed the "dip and dry" technique, its advantages in field analysis are indisputable, boasting in situ deployment, simplicity, and high efficiency, while minimizing interference signals to negligible levels. Through the application of this advanced technique, we have successfully detected TCZ in two high-value crops, ST25 rice and dragon fruit, achieving excellent recovery values ranging from 90 to 128%. This underscores its immense potential in ensuring food quality and safety. As a proof of concept, flexible Paper/f-TiO2/Ag SERS chips, with a simple fabrication process, advanced analytical technique, and superior sensing efficiency, bring SERS one step closer to field applications beyond the laboratory. [ABSTRACT FROM AUTHOR]

This study introduces a novel method for the rapid and efficient detection of paracetamol, leveraging a colorimetric sensing mechanism predicated on the utilization of TMB-MnO2 nanosheets. The interaction of paracetamol with MnO2 is characterized by a selective reaction mechanism, leading to the reduction of MnO2 to Mn2+ ions and consequent attenuation of the oxidase-mimetic activity of MnO2. The developed colorimetric sensor exhibits a linear detection range for paracetamol extending from 5 × 10−4 to 10−2 M, with a lower detection limit quantified at 5.24 × 10−7 M. Empirical assessments conducted to ascertain the influence of potential interferents prevalent in actual samples revealed a negligible impact on the colorimetric sensor. Furthermore, the application of this sensor system to real-world samples demonstrated its capability to detect paracetamol with a notable recovery rate and a relative standard deviation of < 6.65%. This approach manifests significant promise for the efficacious detection of paracetamol in various sample matrices. [ABSTRACT FROM AUTHOR]

Purpose: This paper proposed an adaptation of the theory of planned behavior (TPB) model to study the factors influencing organic food purchase behavior in an emerging market. This research introduced household norms as an important factor that reflected the influence of household activities and family pressure on individuals to perform organic food purchase behaviors. The role of trust in organic food as a direct and a moderating factor was examined in the proposed framework as well. Design/methodology/approach: The study proposed a model with 10 hypotheses from the literature review. The hypotheses were tested using data collected from 407 organic food customers in Hanoi, Vietnam. The partial least squares structural equation modeling (PLS-SEM) approach was used for analysis. Findings: The results indicated that household norms played an important role influencing purchase intention and behavior. This research also showed that trust in organic food directly affected purchase intention and played a moderating role on the attitude towards organic food and purchase intention relationship. However, trust in organic food did not show moderating effects on other relationships in the model. Research limitations/implications: More context-specific reasons may be incorporated into the research model to better explain consumer purchase behaviors. Originality/value: The role of household norms and its impact under TPB has not been investigated for organic food purchase behaviors, particularly in emerging markets. [ABSTRACT FROM AUTHOR]

Nanozymes based on manganese oxide (MnO2) are demonstrated to be promising probes in colorimetric sensing applications. In this study, the r-MnO2/β-MnO2 heterophase nanostructure was simply prepared by a calcination process with controllable temperature. The characterization of the nanostructured material was confirmed by SEM, UV–vis spectroscopy, Raman, TGA–DSC, and XRD analysis. The r-MnO2/β-MnO2 exhibits a remarkably good catalytic activity in the oxidation process of 3,3′,5,5′-tetramethylbenzidine (TMB) compared with the r-MnO2 or Mn2O3 nanostructure owing to its heterophase junctions. The enhanced performance of the colorimetric sensor for ascorbic acid (AA) detection was investigated using the r-MnO2/β-MnO2 heterophase nanostructure as probe. The r-MnO2/β-MnO2 material enhanced the monitoring of AA in the wide linear range from 1 µM to 50 μM with a limit of detection of 0.84 µM. This work presents a promising and straightforward approach for the construction of MnO2-based colorimetric sensor and their practical application in plant growth monitoring. [ABSTRACT FROM AUTHOR]

Wake transitions of flow past two tandem semi-circular cylinders near a moving wall were numerically investigated using the lattice Boltzmann method at the Reynolds number of 150 with various gap ratios (G/D, where G and D are the spacing between the cylinder and wall and the cylinder diameter, respectively) and spacing ratios (L/D, where L is the distance between the cylinder centers). The analysis aims to clarify the effects of L/D and G/D on wake structures, hydrodynamic forces, Strouhal number, and spectral energy of the flow exerted on both cylinders. This study reveals five distinct flow regimes in the L/D-G/D space, such as overshoot, continuous reattachment, pair-wise, quasi-coshedding, and coshedding. These regimes are identified using plots of vorticity contour, time history of drag and lift coefficients (CD and CL), power spectral density, and proper orthogonal decomposition of the vorticity fluctuation into deterministic spatial structures. Furthermore, the flow regime maps and diagrams of time-averaged pressure coefficients on the surface of the cylinders are given to analyze the influence of the moving wall. A significant change in CD and CL is observed for both cylinders, depending on the L/D and G/D ratios. The time-averaged drag coefficient of the downstream cylinder is remarkably lower than that of the upstream cylinder. A significant increase in the time-averaged lift coefficient of the upstream cylinder is observed when the G/D is small due to near-moving wall effects. The root-mean-squared value of the lift and drag coefficients of the downstream cylinder is lower than that of the upstream cylinder as a result of the proximity effect. Meanwhile, the Strouhal number for both cylinders remains mostly the same. [ABSTRACT FROM AUTHOR]

Objective: This article studies whether a firm's environmental, social, and governance (ESG) reputational risk influences board gender diversity. Besides, we are also interested in the moderating role of gender equality and country development level toward the relationship between reputational risk and board gender diversity. Method: Using a comprehensive sample of firms from 52 countries between 2007 and 2019, we employ multiple regression with fixed effects. Our findings remain robust when using alternative measures of variables and addressing endogeneity concerns by employing a two‐stage systems generalized method of moments estimation and an instrumental variable approach. Results: Companies with high levels of ESG reputational risk tend to add more women directors to resolve these problems. Furthermore, the empirical results point out that the positive impact of ESG reputational risk on board gender diversity is more pronounced for countries with a higher degree of gender equality or developed countries. Conclusions: Overall, our study is the first international study to link ESG reputational risk via media channels to board gender diversity. [ABSTRACT FROM AUTHOR]

In this study, we demonstrate the influence of crystallinity and morphology on the analytical performance of various Cu2MoS4 (CMS) nanocatalysts‐based electrochemical sensors for the high‐efficiency detection of Ofloxacin (OFX) antibiotic. The electrochemical kinetics parameters including peak current response (ΔIp), peak‐to‐peak separation (ΔEp), electrochemically active surface area (ECSA), electron‐transfer resistance (Rct), were obtained through the electrochemical analyses, which indicate the single‐crystalline nature of CMS nanomaterials (NMs) is beneficial for enhanced electron‐transfer kinetics. The morphological features and the electrochemical results for OFX detection substantiate that by tuning the tube‐like to plate‐like structures of the CMS NMs, it might noticeably enhance multiple adsorption sites and more intrinsic active catalytic sites due to the diffusion of analytes into the interstitial spaces between CMS nanoplates. As results, highly single‐crystalline and plate‐shaped morphology structures of CMS NMs would significantly enhance the electrocatalytic OFX oxidation in terms of onset potential (Eonset), Tafel slope, catalytic rate constant (kcat), and adsorption capacity (Γ). The CMS NMs‐based electrochemical sensing platform showed excellent analytical performance toward the OFX detection with two ultra‐wide linear detection concentration ranges from 0.25–100 and 100–1000 μM, a low detection limit of 0.058 μM, and an excellent electrochemical sensitivity (0.743 μA μM−1 cm−2). [ABSTRACT FROM AUTHOR]

Throughout the globe morphological, biochemical and genetic variability exists in chilli and is harnessed to achieve specific breeding objectives. In this study, chilli germplasm was characterized based on horticultural traits, biochemical quantification and simple sequence repeat (SSR) polymorphism for diversity estimation. A total of 36 SSR primers were utilised to study the genetic divergence among 48 genotypes of chilli collected from nine states of India. Among the 36 primers, sixteen amplified null alleles. A total of 41 alleles were detected with average 2.05 alleles per locus. The largest number of alleles (5) were obtained with marker CAMS-234. The polymorphic information content ranged from 0.06 to 0.72 with an average of 0.50. On the basis of SSR analysis, the UPGMA cluster classified 48 genotypes into three groups. There was significant variability in germplasm for all morpho-biochemical traits. Kashi Anmol (100.50 q/ha) expressed the highest yield. Highest vitamin C content at green stage was recorded in IC-561635 (187 mg/100 g) and the greatest capsaicin content (9547.90 µg/g) equivalent to pungency of 171,862.2 Scoville heat units (SHU) was recorded in Bhut Jolokia. Principal component analysis indicates that the first five principal components explain 74.63% per cent of the total variation. Additionally, analysis of molecular variance (AMOVA) showed that 1% of the total genetic variation occurred among the population and 99% genetic variation within the populations, whereas the pairwise Fst specified the moderate genetic variation ranging from 0.002 to 0.020. The present investigation has strengthened the knowledge of genetic worth of this germplasm for application in various genetic improvement programmes. [ABSTRACT FROM AUTHOR]

Stomata are specialized pores that play a vital role in gas exchange and photosynthesis. Microscopic images are often used to assess stomatal characteristics in plants; however, this can be a challenging task. By utilizing Matterport's Mask R-CNN implementation as the foundational model, fine-tuning was conducted on a dataset of 810 microscopic images of Hedyotis corymbosa leaves' surfaces for automated stomatal pores detection. The outcomes were promising, with the model achieving a convergence of 98% mean average precision (mAP) for both detection and segmentation. The training loss and validation loss values converged around 0.18 and 0.37, respectively. Regression analyses demonstrated the statistical significance (p values ≤ 0.05) of predictor parameters. Notably, the tightest cluster of data points was observed in stomata pore area measurements, followed by width and length. This highlights the precision of the stomatal pore area in characterizing stomatal traits. Despite challenges posed by the original dataset's low-resolution images and artifacts like dust, bubbles, and blurriness, our innovative utilization of the Mask R-CNN algorithm yielded commendable outcomes. This research introduces a robust approach for stomatal phenotyping with broad applications in plant biology and environmental studies. [ABSTRACT FROM AUTHOR]

This article examines the relationship between corporate social responsibility and earnings management behavior around the world. Using international data from 35 countries between 2003 and 2019, we find evidence that increased corporate social responsibility tends to mitigate the pressure to manage earnings. These findings are robust to alternate measures of earnings management, corporate social responsibility, as well as controlling for endogeneity caveats by two‐stage‐least square and system generalized‐method‐of‐moments estimations. We further show that the negative association between corporate social responsibility and earnings management is more pronounced for firms in countries with high press freedom or high societal trust. The findings from this article provide implications for investors, analysts, business participants, and regulators. [ABSTRACT FROM AUTHOR]

Early neurological deterioration (END) is progressive neurological deterioration with an increase in NIHSS score of 2 points or more in the first 72 hours from the onset of acute ischemic stroke. END increases the risk of poor clinical outcomes at day 90 of ischemic stroke. We will study the frequency, predictors, and outcomes of patients with END in a case-control study at a comprehensive stroke centre in Vietnam. of the design is a descriptive observational study, longitudinal follow-up of patients with minor stroke hospitalized at the Stroke Center of Bach Mai Hospital from December 1, 2023, to December 1, 2024. Minor stroke patients characterized by NIHSS score ≤ 5 hospitalized within 24 hours of symptom onset will be recruited. The estimated END rate is about 30%, relative accuracy ε = 0.11, 95% reliability, expected 5% of patients lost data or follow-up, and an estimated sample size of 779 patients. This study will help determine the END rate in patients with minor stroke and related factors, thereby building a prognostic model for END. Our study determined the END rate in patients with minor stroke in Vietnam and also proposed risk factors for minor stroke management and treatment. [ABSTRACT FROM AUTHOR]

This study aims at evaluating synergistic influences of limestone powder (LP) and unground rice husk ash (URHA) utilizations on comprehensive performances of a slag-cement self-compacting concrete (SCC). In addition, the improved strength efficiency of the binders in concretes due to the additives of LP and/or URHA was also explored. Experimental results illustrated that sole addition of LP partially replacing slag in range of 10–30 mass% remarkably increased 28-day compressive strength of the modified SCC at 17.7% in average as compared with the reference SCC. In addition, the modified SCC with LP in range of 10 to 50 mass% had water absorption reduced at 21.2% in average, 28-day drying shrinkage reduced at 15.7% in average, UPV increased at 29.4%, and total Coulomb passed reduced at 11.6%, which implied the better quality concrete than the reference SCC. By using LP to replace slag at 30 mass% for achieving the best 28-day compressive strength of 61.2 MPa, adding URHA as partial replacement for fine aggregate at the values of 10 vol% and 30 vol% led to the modified SCCs with further improvement on resistance to chloride penetration up to 15.47% reduction on total Coulomb passed as compared with the reference SCC and the best early compressive strengths of 17.5, 37.7, and 53.0 MPa at 1, 3, and 7 days, respectively. [ABSTRACT FROM AUTHOR]

Objective: The ultimate objective of this study was to isolate bioactive compounds from Grewia bulot Gagn. leaves and evaluate their cytotoxicity against a panel of human cancer cell lines. Methods: Compounds were isolated by column chromatography, whereas their chemical structures were elucidated by NMR spectroscopic data, and literature comparison. The cytotoxic activity of the isolated compounds was assessed using SRB assay against 4 cancer cell lines, including MCF-7 (human breast carcinoma), Hep-G2 (human hepatocellular carcinoma), KB (human carcinoma in the mouth), and SK-LU-1 (human lung carcinoma). Results: From the n -hexane extract, 4 compounds were isolated and identified as taraxerol (1), 3-(E)-coumaroyltaraxerol (2), 3-(Z)-coumaroyltaraxerol (3), and lupeol (4). Additionally, 6 compounds were isolated from the ethyl acetate extract and identified as daucosterol (5), trans -tiliroside (6), inugalactolipid A (7), (3 S,5 R,6 S,7 E,9 R)-7-megastigmene-3,6,9-triol (8), biphenyl-3,3′,4,4′-tetrol (9), and smiglabrone B (10). Among these isolates, only compound 9 exhibited moderate cytotoxic activity against all tested cancer cell lines with the IC50 values ranging from 31.67 to 63.15 µM. Conclusion: All these compounds have been detected from G bulot for the first time, biphenyl-3,3′,4,4′-tetrol (9) emerged as a promising candidate for cancer drug development. This study contributes to the growing body of knowledge regarding natural compounds with anticancer properties. [ABSTRACT FROM AUTHOR]

Objectives: This study aims to evaluate the cytotoxicity of compounds isolated from Buxus latistyla Gagnep. against selected cell lines. Methods: The isolation process was carried out using combined chromatographic techniques. The structural elucidation of compounds was achieved by combining 1D-/2D-NMR and HRESIMS data. The absolute configurations of new compounds were also confirmed using ECD experiments. The sulforhodamine B colorimetric assay was employed to assess the toxicity of isolates against tested cell lines. Results: Two new lupane-type derivatives, 3 α -carbomethoxy-3 β -hydroxy-1,3-cyclo-1,2-seco-lup-20(29)-en-1-one (1) (buxlatistylate A) and 1 α -carbomethoxy-1 β -hydroxy-1,3-cyclo-2,3-seco-lup-20(29)-en-3-one (2) (buxlatistylate B), along with five known triterpenes, including lupeol (3), lupenone (4), betulin (5), 20(29)-lupene-2 α,3 α -diol (6), and 20(29)-lupene-2 α,3 α,28-triol (7), were isolated. Compounds 1, 2, 6, and 7 exhibited weak cytotoxic activity against human cancer cells MCF-7, SK-LU-1, and SW480, with IC50 values ranging from 36.33 to 84.16 μM, whereas compounds 3-5 did not show toxicity toward tested cell lines. Conclusion: Compounds 1 and 2 are the first examples of lupane-type triterpenes containing the substituted cyclopentanone A-ring in their molecules. The biosynthetic pathways of these new compounds were also discussed and proposed herein. These findings indicate that B. latistyla holds potential for further in-depth studies on compounds with interesting structures that inhibit human cancer cells. [ABSTRACT FROM AUTHOR]

Purpose. Analysis of the rotor configuration of line start permanent magnet synchronous motor (LSPMSM) when using 3-bar magnet structure with two cases: one with a separating magnetic steel bridge and one without it. Research results allow selecting the appropriate rotor configuration to obtain the best starting characteristics, current, torque, and performance. Thereby, it is possible to replace high efficiency LSPMSM with low efficiency induction motors used in ventilation and water pumping loads to improve the efficiency of electricity use in mining. Methodology. The article uses analytical methods and simulation methods on Ansys/Maxwell software and conducts a laboratory test evaluation to determine the effect of rotor configuration on the starting characteristics, working current, torque ripple, and working efficiency of an LSPMSM for mining applications. Findings. An LSPMSM model was built based on a 15 kW–3,000 rpm induction motor with two rotor configurations: one with a separating magnetic steel bridge and one without it. The results of the study show that when a rotor configuration has no separating magnetic steel bridge, the LSPMSM reaches its maximum speed in 0.45 seconds, a synchronous speed of 3,000 rpm in around 0.75 seconds, a torque ripple of 23.1 %, a current total harmonic distortion of 14.3 %, and a performance of 93.3 %. In contrast, when a rotor structure has a separating magnetic steel bridge, starting the motor is more difficult, taking 1.14 seconds to reach synchronous speed and having a lower starting torque, a current total harmonic distortion of 16.1 %, and a performance of 92.5 %. Originality. Research rotor configurations of LSPMSM based on the 15 kW–3,000 rpm induction motor with and without a separating magnetic steel bridge. The research results allow choosing the appropriate rotor configuration to obtain the best starting characteristics, current, operating torque and performance efficiency. Practical value. The research results are important scientific guidance in the design and manufacture of LSPMSM for application in underground mining to improve the efficiency of electricity use in mining. [ABSTRACT FROM AUTHOR]

In this study, AuPt bimetallic nanocubes (AuPt NCBs) were successfully combined with graphene quantum dots (GQDs) by a simple and easy-to-implement method at 80 °C for 90 min. In particular, graphene quantum dots were synthesized by hydrothermal method at 190 °C for 8 h, using raw material from wheat flour which is eco-friendly, available and abundant in nature. Besides, AuPt bimetallic nanocubes in the form of AuPt core/shell nanocubes (AuPt NCBs) were generated from the reaction at 140 °C for 2 h by hydrothermal method. Furthermore, the synthesized AuPt NCBs/GQDs nanocomposites were also characterized, shape, size and composition by: UV–vis, FTIR, XRD, TEM, EDX, XPS, and AFM. The obtained results show that the Au nanocubes (Au NCBs) have an average size of ~ 39 nm; while, the average size of AuPt NCBs and GQDs are ~ 40–44 and ~ 3–5 nm, respectively. In addition, AuPt NCBs/GQDs nanocomposites were also used as non-enzymatic catalysts for the oxidation/reduction of glucose by cyclic voltammetry technique. The obtained results indicated that the AuPt NCBs/GQDs nanocomposites have high catalytic activity and are capable of detecting glucose in a wide concentration range from 10−12 to 1 M, with an extremely low limit of detection of concentration glucose levels (~ 10−12 M). Therefore, AuPt NCBs/GQDs are novel and promising materials that can be applied as catalysts with high activity oriented to many fields such as environmental treatment, fuel energy cells, or sensors to make bio-chip devices for early diagnosis of serious diseases such as diabetes, gout or cancer, etc., in present and the future. [ABSTRACT FROM AUTHOR]

Citrus fruit yield is essential for market stability, as it allows businesses to plan for production and distribution. However, yield estimation is a complex and time-consuming process that often requires a large number of field samples to ensure representativeness. To address this challenge, we investigated the optimal altitude for unmanned aerial vehicle (UAV) imaging to estimate the yield of Citrus unshiu fruit. We captured images from five different altitudes (30 m, 50 m, 70 m, 90 m, and 110 m), and determined that a resolution of approximately 5 pixels/cm is necessary for reliable estimation of fruit size based on the average diameter of C. unshiu fruit (46.7 mm). Additionally, we found that histogram equalization of the images improved fruit count estimation compared to using untreated images. At the images from 30 m height, the normal image estimates fruit numbers as 73, 55, and 88. However, the histogram equalized image estimates 88, 71, 105. The actual number of fruits is 124, 88, and 141. Using a Vegetation Index such as IPCA showed a similar estimation value to histogram equalization, but I1 estimation represents a gap to actual yields. Our results provide a valuable database for future UAV field investigations of citrus fruit yield. Using flying platforms like UAVs can provide a step towards adopting this sort of model spanning ever greater regions at a cheap cost, with this system generating accurate results in this manner. [ABSTRACT FROM AUTHOR]

In this study, the novel Au/Cu2O/Graphene quantum dots nanocomposites have been synthesized via a fast, simple and environmentally friendly method for the first time. Specifically, Cu2O nanocubes (Cu2O NCBs) synthesized by a reduction reaction at room temperature were combined with Au nanoparticles (Au NPs) and Graphene quantum dots (GQDs) obtained from low-cost and naturally abundant material. The synthesized Au/Cu2O/GQDs were characterized by UV-vis, FTIR, XRD, TEM, FESEM, and EDS. The results show that the Au/Cu2O/GQDs have an average size of about 32-36 nm, in which the diameter of Au NPs is ~28-32 nm, Cu2O particles have the form of nanocube with the size of ~29-33 nm and GQDs are small spherical with an average size of ~5 nm. In addition, the electrochemical properties of the Au/Cu2O/GQDs electrodes were investigated using the cyclic voltammetry (CV) technique. The obtained results show that the Au/Cu2O/GQDs have high electroactivity, which are very potential and promising to be used in glucose sensor with a very wide concentration of glucose detection range from 10-10 M to 1 M with a the LOD of 70 nM (7×10-8 M) and a high sensitivity of 32.5 μAμM-1cm-2. Therefore, Au/Cu2O/GQDs will be potential candidate for non-enzymatic sensitive glucose sensors in the future. Cu2O nanocubes (Cu2O NCBs) were successfully combined with Au nanoparticles (Au NPs) and Graphene quantum dots (GQDs) to generate Au/Cu2O/GQDs nanocomposites. The properties and morphology of synthesized Au/Cu2O/GQDs were also studied. Au/Cu2O/GQDs showed promising electrochemical activity and performed its applicability for glucose detection with a wide concentration of glucose detection range from 10-10 M to 1 M. [ABSTRACT FROM AUTHOR]

Citrus fruit yield is essential for market stability, as it allows businesses to plan for production and distribution. However, yield estimation is a complex and time-consuming process that often requires a large number of field samples to ensure representativeness. To address this challenge, we investigated the optimal altitude for unmanned aerial vehicle (UAV) imaging to estimate the yield of Citrus unshiu fruit. We captured images from five different altitudes (30 m, 50 m, 70 m, 90 m, and 110 m), and determined that a resolution of approximately 5 pixels/cm is necessary for reliable estimation of fruit size based on the average diameter of C. unshiu fruit (46.7 mm). Additionally, we found that histogram equalization of the images improved fruit count estimation compared to using untreated images. At the images from 30 m height, the normal image estimates fruit numbers as 73, 55, and 88. However, the histogram equalized image estimates 88, 71, 105. The actual number of fruits is 124, 88, and 141. Using a Vegetation Index such as IPCA showed a similar estimation value to histogram equalization, but I1 estimation represents a gap to actual yields. Our results provide a valuable database for future UAV field investigations of citrus fruit yield. Using flying platforms like UAVs can provide a step towards adopting this sort of model spanning ever greater regions at a cheap cost, with this system generating accurate results in this manner. [ABSTRACT FROM AUTHOR]

Similar to most anthraquinone compounds, the pharmacological properties of emodin are limited because of its low water solubility. In this study, the formulation of chitosan and emodin (EMD/CS) was prepared by a bottom-up method with precipitation and sonication steps in order to enhance the solubility of emodin. Thanks to the interactions of oxygen-and nitrogen-containing groups in chitosan with emodin molecules, the solubility of emodin in the formulation was remarkably increased to 0.5 mg/mL. The EMD/CS particles were well dispersed and distributed in a range of sub-micrometer with an average particle size of 342 nm. The EMD/CS formulation exhibited synergic antibacterial activity of emodin and chitosan, against drug-resistant bacterial strains, namely Methicillin-resistant Staphylococcus aureus (MRSA) and Escherichia coli O157:H7 (E. coli O157:H7). When the compositions of emodin and chitosan increased, the antibacterial effectiveness of the EMD/CS formulation increased. The EMD/CS formulation with compositions of 0.5 mg/mL of emodin and 9.0 mg/mL of chitosan could significantly inhibit the proliferation of E. coli O157:H7. Meanwhile, the EMD/CS formulation with a lower concentration of emodin (0.4 mg/mL) and chitosan (7.2 mg/mL) could cause an extermination effect on MRSA. The enhanced solubility of EMD/CS formulation suggests that this formulation can be a potential candidate for the treatment of infectious diseases caused by drug-resistant bacterial pathogens. [ABSTRACT FROM AUTHOR]

Dynamic flows past three tandem elliptic cylinders of equal spacing in parallel arrangement with a moving wall are numerically conducted by the lattice Boltzmann method. The gap ratio (G/D, where G and D are the gap between the wall surface and cylinder center and major axis, respectively) from 0.6 to 2.5 and spacing ratio (L/D, where L is the distance of two adjacent cylinder centers) from 1.5 to 10 are examined at Reynolds number of Re = 150 (based on D). The desired analysis correlates variations of hydrodynamic coefficients, wake structures, and spectral analysis in wide space of G/D and L/D with underlying fluid mechanics. The flow is highly adjustable in G / D − L / D space, dividing into six distinct regimes: overshoot, continuous reattachment, alternative reattachment, wavy, meandering, and coshedding, which are spatially classified into four modes because of flow interference, namely, shear layer, primary, two-layered, and secondary vortex shedding modes. The transition between adjacent modes defines three boundaries. The first boundary always occurs behind the middle or downstream cylinder, whereas the second and third boundaries occur between the upstream and middle cylinders and the downstream cylinder wake. Due to the near-wall flow interference, the hydrodynamic coefficients are highly changeable in L / D − G / D space, signifying the crucially lower drag coefficient of the middle and downstream cylinders than that of a single cylinder. A small G/D determines the increase in lift coefficient of the upstream cylinder as a result of the ground effect, while the shadowing effect of the upstream cylinder induces identical Strouhal numbers of the middle and downstream cylinders. [ABSTRACT FROM AUTHOR]

Nano-constituent incorporation into composites has been extensively studied in the literature due to its improvement in static and dynamic mechanical properties, as well as its prevention from interlaminar crack initiation and propagation. This work introduces a detailed manufacturing process of nano-engineered composite laminates, from impregnation to consolidation, without damaging the initial morphology of carbon nanotubes transferred on prepreg interfaces. Based on prepreg and vertically aligned carbon nanotubes (VACNTs) synthesized on an aluminium alloy (Al) substrate, the impregnation step allows for the transfer of VACNTs onto the prepreg surface through partial resin-rising capillarity. The Al alloy substrate is then removed from the VACNTs through a separation step, ensuring highly effective and repeatable transfer with more than 80% VACNTs transferred onto the prepreg surface. This paper provides insight into the impregnation and transfer processes and guides the choice of process parameters to ensure minimal VACNTs buckling during the consolidation of the hybrid composites at high pressure in an autoclave. [ABSTRACT FROM AUTHOR]

In this research, I established an energy benchmark for the pulp and paper industry of Vietnam. I, therefore, focus on three major paper product families, including packaging paper, printing and writing paper, and tissue paper. In this research, I use specific energy consumption (SEC) as the energy performance indicator (EnPI) for computing energy benchmarks for the main sub-sectors in the pulp and paper industry of Vietnam. The factories in the pulp and paper industry of Vietnam are divided into three production scales, and the energy benchmarks are specified by production scales. Energy surveys and energy audits have been used to calculate energy benchmarks. Here, I establish the energy benchmark for the main sub-sectors in the pulp and paper industry of Vietnam according to the three production scales. I also estimate the energy saving potential for the pulp and paper industry of Vietnam based on surveying and auditing results. [ABSTRACT FROM AUTHOR]

While steel slag is widely used in many countries as an environmentally benign building and backfill materials, it has not been used in Vietnam. This is because steel slag is naturally radioactive and has been treated as radioactive waste; however, there has not been any study to evaluate the natural radioactivity. This paper presents the results of an investigation and evaluation of the potential use of Vietnamese steel slag as a building material. Although the presence of natural isotopes, such as 226Ra, 232Th, and 40K, were confirmed in the steel slag samples, the calculated radioactivity index I for all samples did not exceed the nominal thresholds for building construction, landfill, and landscaping applications specified in the Finland standard STUK ST 12.2/2012 and the Vietnamese standard TCXDVN 397:2007. Therefore, the Vietnamese steel slag is not a radioactive waste and can be used as building and backfill materials without environmental risk in terms of natural radioactivity. The findings of this study will be beneficial not only to Vietnam, but also to other countries that are having trouble reusing steel slag for similar reasons. [ABSTRACT FROM AUTHOR]

We demonstrate a sideband-resolved cavity electromechanical system operating at room temperature. It consists of a nanomechanical resonator, a strongly pre-stressed silicon nitride string, dielectrically coupled to a three-dimensional microwave cavity made of copper. The electromechanical coupling is characterized by two measurements, the cavity-induced eigenfrequency shift of the mechanical resonator and the optomechanically induced transparency. While the former is dominated by dielectric effects, the latter reveals a clear signature of the dynamical backaction of the cavity field on the resonator. This unlocks the field of cavity electromechanics for room temperature applications. [ABSTRACT FROM AUTHOR]

This study focuses on predicting the online purchase intention of consumers purchasing from e-commerce platforms using an integrated model of the theory of planned behavior (TPB) and extended technology acceptance model (TAM). The results showed that TAM factors, perceived value, and perceived enjoyment had significant effects on attitude toward online purchase, while the TPB inputs, perceived enjoyment, and e-commerce exchange image played strong roles in influencing online purchase intention. The results also showed that perceived enjoyment helped to raise the predictive power of attitude dramatically, while the e-commerce exchange image contributed a high portion to explain online purchase intention variation. The results indicated that the e-commerce trading platforms need to focus on improving their images and on increasing customers' experience to improve their business performance. Plain Language Summary: Prediction of online purchase intention on e-commerce platforms This study focuses on predicting the online purchase intention of consumers purchasing from e-commerce platforms using an integrated model of the theory of planned behavior (TPB) and technology acceptance model (TAM). The study proposed a model with 13 hypotheses from the literature review. The hypotheses were tested using data collected from 326 e-commerce consumers in Vietnam. The PLS-SEM approach was used for analysis. The results showed that TAM factors, perceived value and perceived enjoyment had significant effects on attitude towards online purchase, while attitude, perceived enjoyment and e-commerce exchange image played strong roles influencing online purchase intention. The results also showed that the perceived enjoyment helped to raise the predictive power of attitude dramatically, while e-commerce exchange image contributed a high portion to explain online purchase intention variation. Other specific contextual factors may be incorporated into the integrated model to better explain online purchase intention. The results indicated that the e-commerce trading platforms need to focus on improving their image and on increasing customers' experience in order to improve their business performance. This is among the first studies that investigates the integration of the TPB and TAM for e-commerce behavioral intention research incorporating e-commerce exchange image as an important factor that affects online purchase intention. The new integrated model has verified its value to considerably enhance the capability to predict the variations of attitude towards online purchase and online purchase intention. [ABSTRACT FROM AUTHOR]

Titanium dioxide (TiO2) nanomaterials have been comprehensively studied in recent decades because of their possible practical applications in diverse fields, including photocatalysis, energy storage, sensing and biomedicine. Numerous strategies have been reported on preparing TiO2 nanostructures with regulated sizes, shapes and surface ligands; however, developing a simple, eco-friendly, cost-effective and scalable procedure for the fabrication of TiO2 nanomaterials while controlling those properties is still challenging. Herein, titanium dioxide nanostructures, e-TiO2, are prepared using a scalable green electrochemical approach, in which Ti foils act as precursors. Electrolysis is carried out in an electrolyte solution containing only a surfactant in water. This approach reduces the use of toxic chemicals, and thus it is eco-friendly and cost-effective. Moreover, the electrochemical synthesis of colloidal e-TiO2 can be successfully scaled up to 5 L. Three cationic surfactants, tetrapropylammonium bromide (TPAB), tetrabutylammonium bromide (TBAB) and cetyltrimethylammonium bromide (CTAB), are employed as electrolytes to fabricate e-TiO2, resulting in the formation of three types of nanostructures: negatively charged e-TiO2/TPAB nanospheres, negatively charged e-TiO2/TBAB nano-ellipses and positively charged e-TiO2/CTAB nanorods. They are characterized to clarify the roles of surfactants in controlling sizes, shape and surface properties of e-TiO2 nanostructures. Dispersibility of three types of e-TiO2 is investigated in aqueous and nonpolar solvents. e-TiO2/TPAB and e-TiO2/TBAB are only well-dispersed in aqueous media. In particular, e-TiO2/CTAB can be dissolved in both kinds of solvents. Thanks to the unique rotatable property of the coating agent (CTAB), a "smart" TiO2 nanomaterial (e-TiO2/CTAB nanorod) has been fabricated, which can migrate from an aqueous medium to a nonpolar one and vice versa. [ABSTRACT FROM AUTHOR]

Precision agriculture employs cutting-edge technologies to increase agricultural productivity while reducing adverse impacts on the environment. Precision agriculture is a farming approach that uses advanced technology and data analysis to maximize crop yields, cut waste, and increase productivity. It is a potential strategy for tackling some of the major issues confronting contemporary agriculture, such as feeding a growing world population while reducing environmental effects. This review article examines some of the latest recent advances in precision agriculture, including the Internet of Things (IoT) and how to make use of big data. This review article aims to provide an overview of the recent innovations, challenges, and future prospects of precision agriculture and smart farming. It presents an analysis of the current state of precision agriculture, including the most recent innovations in technology, such as drones, sensors, and machine learning. The article also discusses some of the main challenges faced by precision agriculture, including data management, technology adoption, and cost-effectiveness. [ABSTRACT FROM AUTHOR]

Taking advantage of metal–semiconductor junctions, functional nanocomposites have been designed and developed as active substrates for surface-enhanced Raman scattering (SERS) sensing systems. In this work, we prepared three types of nanocomposites based on manganese oxide (MnO2) nanostructures and electrochemically synthesized silver nanoparticles (e-AgNPs), which differed according to the morphologies of MnO2. The SERS performance of MnO2 nanosheet/e-Ag (MnO2-s/e-Ag), MnO2 nanorod/e-Ag (MnO2-r/e-Ag), and MnO2 nanowire/e-Ag (MnO2-w/e-Ag) was then evaluated using tricyclazole (TCZ), a commonly used pesticide, as an analyte. Compared to the others, MnO2-s/e-Ag exhibited the most remarkable SERS enhancement. Thanks to its large surface area and ability to accept/donate the electrons of the semiconductor, MnO2-s acted as a bridge to improve the charge transfer efficiency from e-Ag to TCZ. In addition, the MnO2 content of the nanocomposites was also considered to optimize the SERS sensing performance. With the optimal MnO2 content of 25 wt%, MnO2-s/e-Ag could achieve the best SERS performance, allowing the detection of TCZ at concentrations down to 6 × 10−12 M in standard solutions and 10−11 M in real rice samples. [ABSTRACT FROM AUTHOR]

Delamination still remains one of the common concerns in continuous fibers reinforced polymer composites. In the literature, the incorporation of nanoconstituents into constitutive composites plies has been suggested with the aim of improving interface toughness. In this study, vertically aligned carbon nanotubes forests (VACNTs) are transferred at composites interfaces, and mode I (DCB tests) and mode II (ENF tests) fracture tests carried out on composite samples. Microscopic analysis of reference and nano‐engineered composites help to understand fracture behavior and toughness. While the crack path in ENF samples is observed at interlaminar VACNTs‐resin interfaces, the crack path in DCB samples is intralaminar, located within the unidirectional carbon fiber plies. These microscopic observations give explanation for unstable crack propagation in nano‐engineered ENF samples and the unchanged toughness from the nano‐engineered to the reference zone in DCB samples. [ABSTRACT FROM AUTHOR]

Summary: A new species, Garcinia phuongmaiensis V.S.Dang, H.Toyama & D.L.A.Tuan (Clusiaceae), discovered from Phuong Mai Peninsula, Nhon Hoi Commune, Quy Nhon City, Binh Dinh Province, central Vietnam, is described and illustrated. This new species is similar to G. prainiana King, but is distinguished by smaller habit, leaves and flowers with white petals. A description, preliminary conservation assessment, illustration, photographs and vernacular name of the new species are provided, as well as an updated key to the species of Garcinia sect. Xanthochymus in Indo-China. [ABSTRACT FROM AUTHOR]

This study investigated the effects of corruption and economic freedom on corporate leverage. We also evaluated how economic freedom shapes the effect of corruption on corporate leverage. Using a sample of Vietnamese firms covering a nine‐year period from 2010 to 2018, we find evidence that increased control of corruption has a significant positive impact on firm leverage, whereas the opposite is true for economic freedom. This effect is robust to alternative measures of control of corruption as well as advanced estimation methods, such as firm‐fixed effects and quantile regressions. Our results also reveal that the positive impact of corruption controls on corporate leverage is more pronounced for firms with high economic freedom. Econometrically, our findings indicate that firms with better control over corruption prefer debt financing, as demonstrated by their higher leverage ratio. [ABSTRACT FROM AUTHOR]

This paper proposed a comprehensive model to examine (resource-based) factors affecting management and technological innovation, and in turn the impacts of management and technological innovation on organisational performance in auditing service sector. The results confirmed the significant impacts of all proposed factors on management and technological innovation directly or indirectly. Among proposed factors, internal source involvement showed its direct impact and its mediating effect as well. The results also attested the positive impacts of management and technological innovation on audit firm performance. Contextual factors (organisational size and age) were identified to have significant influences on organisational performance. In addition, organisational age showed its moderating role on the relationship between management innovation and operational performance. The moderating effects indicated that management innovation caused higher impact on younger audit firms. [ABSTRACT FROM AUTHOR]

Plant essential oils have been used for hundreds of years as natural medicines to combat a multitude of pathogens, including bacteria, fungi, and viruses. The paper reports the chemical compositions of essential oil hydrodistilled from the leaves and rhizomes of Amomum unifolium Gagnep. from Vietnam. The main classes of compounds present in the essential oils were monoterpene hydrocarbons (10.1% and 23.9%, respectively), oxygenated monoterpenes (14.5% and 4.9%, respectively), sesquiterpene hydrocarbons (40.9% and 21.9%, respectively), and oxygenated sesquiterpenes (20.1% and 26.8%, respectively). Diterpenes (16.1%) were identified in sizeable proportion in the rhizome essential oil. The constituents occurring in higher amounts in the leaf essential oil were aromadendrene (6.9%), occidenol (6.8%), β-phellandrene (6.2%), β-elemene (5.7%), and δ-elemene (5.0%). However, the main compounds of the rhizome essential oil were β-phellandrene (18.5%), torulosol (16.1%), germacrene D (5.7%), α-cadinol (5.5%) and (6S, 7R)-bisabolene (5.1%). The leaf essential oil of A. unifolium displayed higher antibacterial activity than the rhizome oil. The leaf oil showed activity towards S. aureus ATCC 6538, and B. pumilus ATCC 14884, with MIC values of 75.0 μg/mL and 37.5 μg/mL, respectively. On the other hand, the rhizome essential oil displayed activity against the organisms at MIC value of 150.0 μg/mL. Both essential oils exhibited antibacterial activity to E. coli ATCC 8739, with MIC value of 150.0 μg/mL. The antimicrobial activity of A. unifolium essential oils are being reported for the first time as a confirmation of the ethnomedical uses of A. unifolium in the treatment of diseases especially antimicrobial infections. Furthermore, the paper discusses the chemotaxonomy of Amomum oil samples. [ABSTRACT FROM AUTHOR]

The introduction of nanocatalysts into electrochemical sensing systems has opened up new opportunities in developing advanced electrochemical sensing devices with high sensitivity, selectivity, and stability. In this study, a novel electrochemical sensor for the accurate determination of ofloxacin in a pharmaceutical sample (i.e., in commercial eye drops) was developed using active-site-rich Cu2MoS4 nanoplates as an excellent electrocatalytic platform. The electrocatalytic activity of the Cu2MoS4 nanoplates was investigated using cyclic voltammetry and sweep linear voltammetry techniques. The results obtained demonstrated that the Cu2MoS4 nanoplates exhibit a superior electrocatalytic activity toward the electrochemical oxidation of ofloxacin, thus promoting the sensitive detection of ofloxacin. The ofloxacin oxidation peak current response for Cu2MoS4/SPE (screen-printed electrode) was 2.65 times higher than that of the bare SPE. Under optimal conditions, the Cu2MoS4 nanoplate-based electrochemical sensor exhibited a linear range from 0.625 to 100 μM with a limit of detection (LOD) of 0.067 μM. Importantly, the proposed sensor showed excellent accuracy in comparison with UPLC-MS/MS analysis (RSD < 3.89%), with good interference immunity, high stability, and repeatability (RSD < 6.3%, n = 20). The obtained results demonstrate the promising applications of transition metal chalcogenide-based electrocatalysts in developing advanced electrochemical sensors. [ABSTRACT FROM AUTHOR]