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EVALUATING THE SEGMENT ANYTHING MODEL ON THE AGARWOOD RESINOUS COMPOUNDS SEGMENTATION TASK
Get PDFThe manual extraction of Agarwood resinous compounds is not only labour-intensive and reliant on skilled workers but also prone to wastage due to human errors. The commercial Agarwood industry has increasingly explored the use of Computer Numerical Control (CNC) machines. These machines interpret G-code scripts derived from binary images, where regions of wood marked for chiselling are represented by an RGB value of (0, 0, 0). Instead of relying on manual marking, we propose employing a deep learning-based approach. Our proposed setup involves capturing cross-sectional images using a stationary camera. These images are then transmitted to a computer for the image-based segmentation task. The produced segmented area is translated into a G-code script for the CNC machine. In this article, we present the preliminary results of a prototype of our proposed setup. Additionally, we discuss potential enhancements aimed at refining segmentation accuracy
Polyurethane-electrode modified to determine histamine in selected samples using chemical sensor
Get PDFFood safety is an imperative part of public health that needs to be considered to ensure human health. Histamine is a compound that is easily found in food protein. Thus, analyzing histamine in food before distributing it to the market is essential. The present study discusses applying chemical sensors to evaluate histamine levels in fish samples. The screen-printed electrode (SPE) was applied in this study and modified using bio-polyurethane (PU). The PU was produced using an electropolymerized approach, and the PU was characterized using FTIR to investigate the functional group, the cyclic voltammetry (CV) to study the conductivity, and electrochemical impedance spectroscopy (EIS) to study the resistance of PU after combined with histamine. Furthermore, differential pulse voltammetry (DPV) was employed to validate the histamine detection. The chemical sensor recorded a linear range from 10−3 – 10−1 nmol‧L−1 at the 0.002 nmol ‧L−1 limit of detection (LOD). The sensor can analyze histamine in selected samples at room temperature and obtain satisfactory outcomes. Furthermore, the sensor can be categorized as a fast technique and suitable for on-site analysis
Kinetic Study and Simulation of Titanium Carbide-Supported, Platinum-Doped Tetrahedral Amorphous Carbon Electrodes for Hydrogen Evolution Reaction
No full textThis paper presents the kinetic study of titanium carbide (TiC)-supported, platinum-doped tetrahedral amorphous carbon (taC:Pt) referred to as TiC-taC, for the hydrogen evolution reaction (HER). This study employs the Volmer–Heyrovsky–Tafel (VHT) mechanism. A theoretical approach was utilized to investigate the kinetic properties of these materials for an HER in 0.5 M H2SO4. TiC-taC exhibited Volmer-dominated reactions with a Tafel slope of 40 mV/dec and the overpotential at 10 mA/cm2 was 185 mV. In contrast, isolated TiC and taC:Pt recorded significantly higher Tafel slopes with 60–110 mV/dec and overpotentials of 871 mV and 1009 mV, respectively. The developed model was tested in one dimension (1D) for individual TiC and taC:Pt. The simulated kinetics parameters were determined for both TiC and taC:Pt, revealing that TiC follows the VHT steps, while taC:Pt follows the VH steps. The simulation results show excellent coherence with the experimental results. Further simulation of the hybrid TiC-taC electrocatalyst was conducted considering surface diffusion and edge effects in two (2D) and three dimensions (3D). To the best of our knowledge, this FEM simulation approach is the first to be reported due to the unique geometry of the TiC-taC catalyst enabling the assumption of surface diffusion and edge effect. The introduction of edge effects on the taC:Pt side of the TiC support significantly enhanced the current output, aligning closely with experimental results. The edge exhibited distinct kinetic properties compared to both TiC and taC:Pt. The kinetic parameters determined from the simulation demonstrated strong agreement with experimental findings. Adding the edge effects was essential to explaining the higher current output from the TiC-taC electrode. It exhibited unique kinetic properties not observed in either TiC or taC:Pt alone, acting as a pump where it absorbs cHs from neighbouring sites due to surface diffusivity and releases H2 via the Heyrovsky reaction. While surface diffusion had a lesser effect, the simulation indicated its positive influence on the HER
New haplotypes of AvrPi-54 gene detected in Pyricularia oryzae from Malaysia, India and China
Get PDFPyricularia oryzae, the causal agent of rice blast disease, poses a significant threat to rice production. Limited information exists regarding the genetic diversity of Avr genes and the resistance profile of Sarawak rice against P. oryzae isolates in Malaysia. This study aimed to investigate the sequence variation of the AvrPi-54 gene in P. oryzae isolates from Sarawak rice, in comparison with sequences available in the National Centre for Biotechnology Information (NCBI) database. A total of 20 P. oryzae isolates were analyzed together with 98 AvrPi-54 gene sequences from NCBI. Nine distinct haplotypes were identified, including six novel haplotypes. The AvrPi-54 gene was found to be under positive selection pressure. Notably, Sarawak rice exhibited varying levels of susceptibility to P. oryzae isolates carrying the H1 haplotype. Understanding the genetic diversity of AvrPi-54 together with other Avr genes is crucial for developing effective strategies to manage P. oryzae in Sarawak, Malaysia
International Students' WeChat Use, Prior Cross-Cultural Exposure, Social Self-Efficacy and Cross-Cultural Adaptation in China
Get PDFPrevious research indicates that the cross-cultural adaptation of international students in China is influenced by WeChat and social self-efficacy. Cross-cultural exposure has also been found to influence cross-cultural adaptation in other contexts. However, the mechanisms for these causal relationships are unclear . This study examined the indirect relationship between WeChat use and cross-cultural adaptation among Chinese international students by testing a moderated mediation model. Questionnaire data were collected from 404 international students in four universities in western China. The results show that international students in China have a high level of WeChat use, social self-efficacy, and cross-cultural adaptation, and a moderate level of prior cross-cultural exposure. The Pearson correlation tests showed a significant high correlation among the international students’ WeChat use, social self-efficacy, and cross-cultural adaptation. There was a low but significant correlation between prior cross-cultural exposure and WeChat use, social self-efficacy, and cross-cultural adaptation. Regression analyzes showed that there were indirect influences between WeChat use and cross-cultural adaptation among international students in China. Social self-efficacy has a partial mediating effect. Cross-cultural exposure moderates the base level of their cross-cultural adaptation. If WeChat use is set aside, the international students also experience better cross-cultural adaptation when they have high social self-efficacy. The study indicates that there is a mediating influence pathway of social self-efficacy in the association between WeChat use and cross-cultural adaptation, and that this mediating process is further moderated by prior cross-cultural exposure. The study shows that it is important to have prior-departure programmes to give prospective international students cross-cultural exposure and build their social confidence and competence in handling social interactions in a new environment
Parametric Study of The Microstrip U-Slot Patch Antenna for Concrete Strength Monitoring
Get PDFThis paper presents a parametric study of a microwave microstrip patch antenna based using finite element modelling software to conduct simulations applied to dielectric material characterization. A probe-fed U-slot patch antenna has been designed to function as a material sensing applicator. The primary objective of this study is to provide non-destructive measurements for predicting the grades of cast concrete in the construction industry. The size, shape, and dimensions of the designed patch antenna are described in detail. The parametric study focuses on the shift in the minimum peak of return loss, |S11| (dB) of the antenna in relation to changes in the dielectric constant of the material under test. The modelling done on the antenna show a significant response in the |S11|, when placed on materials selected to simulate concrete samples at different periods of the curing process, and also at different strength grades. It is known that different strength grades of concrete have varying relative permittivity and dielectric constant values. Consequently, the shift in the minimum peak of the measured |S11| (dB) correlates with changes in concrete strength, thus offering a simple, non-destructive, fast, and effective system for testing concrete quality
Seasonal variation in activity budgets of critically endangered Bornean banded langur, Presbytis chrysomelas chrysomelas in Malaysian Borneo
Get PDFThe activity budget of a primate varies in response to environmental and habitat conditions, including seasonality. To elucidate how primates adapt their behavior to the seasonal shift, the activity budget of Bornean banded langurs (Presbytis chrysomelas chrysomelas) in the Tanjung Datu National Park southwestern of Sarawak and stratum utilization were studied from July 2023 to February 2024. The behavioral data were collected through scan sampling (336 observation hours) of Bornean banded langur groups. Overall, the langurs allocated most of their time to resting (35.4%), feeding (32.3%), moving (16.2%), vocalizing (9.2%), and social activities like grooming and playing (6.9%). The seasonal variation was evident, with increased foraging and social activities during the dry season and a greater allocation of time to locomotion during the wet season. Additionally, the Mann-Whitney U test revealed significant seasonal fluctuation in social activities (grooming and playing, P0.05). Food availability and distribution may influence the langur activity budget, with increased travel distance during the wet season because of food scarcity. The langurs predominantly use stratum C (21–30 m) to feed, rest, move, and socialize. This study highlights the seasonal ecology of this critically endangered endemic primate and underscores the importance of habitat conservation efforts to ensure the sustainability of their populations amid environmental changes
Development of single nucleotide polymorphisms markers associated with disease resistance towards Pseudomonas koreensis in empurau (Tor tambroides) using T‑Plex ARMS PCR assay
Get PDFEmpurau is a highly sought freshwater fish with high market value due to its unique flesh taste. However, the main challenge of the industry remains the infectious disease outbreak, with Pseudomonas species as one of the most threatening fish pathogens while residing in a wide range of environments. Antibiotic use is a common solution to disease outbreaks and leads to increased antimicrobial resistance. The development of disease-resistant broodstock through the identification of SNP markers has emerged as a promising strategy. In this study, a total of 1,048,576 SNP markers were identified via whole genome pooled sequencing on samples treated with LD50, forming resistant and susceptible groups. Multiple tests (pairwise FST test, CMH test, and FE test) and visualization were conducted to screen and select candidate SNP markers for further validation using T-plex ARMS real-time PCR assay. The genotyping results on the selected candidate markers were confirmed using Sanger sequencing. Statistical analysis was performed to validate the significance of the candidate markers. The successful validation of 19,564 G/C SNP markers is hoped to contribute to research focusing on disease-resistant association SNPs, enabling the application of genomic information to enhance artificial selection strategies in Tor tambroides (empurau) breeding
Two new species of Hampala from Borneo (Teleostei: Cyprinidae)
Get PDFTwo new species of Hampala are described from Borneo Island. Hampala lupar, new species, is closely allied to H. bimaculata but differs in having three black bars on the body, vs. two bars; with the additional black bar just posterior to head. Hampala lupar is distinguished from all congeners by the following combination of characters: lateral line scales 26–27; three black bars on body, even at juvenile stage; upper and lower edges of caudal fin with a black marginal stripe; all fins orange with caudal fin reddish-orange when alive. Hampala katibas, new species, is similar to H. bimaculata but differs in having two large black blotches on the body, vs. two curved black bars; amongst other characters. Both new species are separated by the Lupar Geological Divide
An explainable machine learning model for encompassing the mechanical strength of polymer‑modified concrete.
Get PDFPolymer-modifed concrete (PMC) is an advanced building material with more excellent durability, tensile strength, adhesion,and lesser susceptibility to chemical degradation. Recent developments in machine learning (ML) have shown that prediction of compressive strength (CS) of PMC key input factors needed to obtain an optimized mix design are among the areas of applicability of ML. This study used eight machine learning models, which are Decision Tree, Support Vector Machine,K-Nearest Neighbors, Bagging Regression, XG-Boost, Ada-Boost, Linear Regression, Gradient Boosting to predict compressive strength and perform SHAP (Shapley additive explanation) analysis. These hybrid predictive PMC models were
developed using a wide-ranging dataset of 382 experimental data points compiled from the literature. A SHAP interaction
plot was also used to show how each feature affected predictions on the model outputs. As highlighted in the results, hybrid models had significantly higher performance than conventional models, and the XG-Boost and decision tree model had the highest accuracy. In particular, the XG-Boost and decision tree model reached R2 scores of 0.987 for training and 0.577 for testing, proving its remarkable prediction ability for PMC compressive strength. The SHAP analysis confirmed that coarse aggregate, cement, and SCMs had the most significant influence on CS, with all other variables contributing lower values. The Partial Dependence Plots (PDP) analysis allowed a relatively simple interpretation of the contribution of individual inputs to the CS predictions. These results are useful for construction purposes and provide engineers and builders with first-hand knowledge and insight into the importance of individual components on PMC development and performance