OJS [Pandawa Inst.]
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A Mathematical Model of an Electoral Process and Predicting of Outcome
No full textWe developed and analysed a mathematical model to study the dynamics of an electoral process and predict the outcome in Nigeria with three political parties as major actors. We model the ruling party; major opposition party and minority opposition parties. The model includes party campaigners of the three political parties and a class of eligible voters. The model also incorporates the Independent National Electoral Commission (INEC), electoral observers, judiciary, security personnel and thugs. The influx of voters into the system is determined by the registration rate of voter cards. The model’s interest lies in the measure of positive influence that the party campaigners who eligible voters to join their party. With this, the model mirrors election’s outcome and the movement of voters between the three groups of political parties involved. The model has proven that the pattern of election’s outcome for each political party is affected by the defection of party members and lack of policy consistency. We determine the equilibria analytically and discuss the stability of the system. Numerical simulations are graphed in combination with curve fitting to compare each party’s performances over the years. The result shows that no political party remains in power steadily from 2007 to 2019. Thus, the prediction of elections outcome to the political space of any region in Nigeria depends on political party structures and voters’ decisions
Comparative Analysis Between Two Reliability Models of a Three-Unit Complex Industrial System
No full textA comparative analysis between two reliability models of a three-unit complex industrial system has been presented in this paper. Previously, real failure-maintenance data of a three-unit complex industrial system were collected. The situations depicted in the data were used for developing two appropriate reliability models for the system. Important reliability indicators of the system were estimated by applying Semi-Markov and regenerative processes. Here, a comparison between the reliability indices and profits of the two models is performed, which helps in identifying the suitability of one model over the other. Cut-off points for profits based on costs, revenues, and failure rates have also been obtained for deciding which of the two models is more profitable. Graphical analysis is also presented to illustrate the outcomes
Catalytic Reduction of 4-Nitrophenol and Methylene Blue with Silver Nanoparticles Decorated with Drymoglossum piloselloides Extract
No full textDrymoglossum piloselloides is one of the epiphytic plants that is commonly found in Southeast Asia region. In this study, the ethanol extract of D. piloselloides plant has been used in the green synthesis of silver nanoparticles. The synthesized silver nanoparticles were characterized by ultraviolet-visible (UV-Vis) spectrophotometry, X-ray diffraction (XRD),Fourier-transform infrared (FTIR) spectroscopy, and transmission electron microscopy (TEM) measurements. The UV-Vis spectrum of silver nanoparticles showed a maximum wavelength at 453 nm. The XRD measurement showed the silver nanoparticles peaks at 38.38°, 44.60°, 64.76°, and 77.62°. The FTIR spectra provided evidence of the interaction between silver and chemicals in the plant extract as a weak signal at 682 cm-1. Meanwhile, TEM revealed an average size of 12.63nm. The synthesised silver nanoparticles were utilised for the reduction of 4-nitrophenol with a conversion percentage of up to 100% with a reduction reaction rate constant of 7.104 s-1. In addition, methylene blue was also successfully reduced with the synthesised silver nanoparticles as the catalyst with a reduction reaction rate constant (k) of 21.150 s-1. This study highlights the superior advantage of utilizing ethanolic extract of D. piloselloides to prepare silver nanoparticles with promising catalytic reduction purposes
Chicken Eggshell Powder as Antibacterial Against Staphylococcus aureus and Escherichia coli Through In Vitro Studies
No full textIdentifying the most effective material with antibacterial properties against Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli) is a challenging task considering the rising concerns about drug resistance. Various experiments through in vitro and in vivo studies to obtain antibacterial agents using abundant and easily available raw material sources have been conducted. Therefore, this study aimed to acquire semiconducting nanoparticle material derived from purebred chicken eggshell waste that could effectively function as an antibacterial agent. The waste treatment was carried out using a top-down method applying the thermal decomposition method with calcination temperatures of 700 and 800 ºC for 30 hours. XRD analysis results showed CaO as a major phase and this was further supported by Rietveld calculation. The size of the crystalline phases obtained ranged from 10–45 nm, while FTIR analysis showed the appearance of CaO bond at a wave number of 715.65 cm-1. Furthermore, SEM analysis showed a rough folded particle surface with a pore percentage of 48.20%. Based on the UV-Vis DRS analysis results, chicken eggshell powder had band gap energy characteristics of 2.07, 2.74, 3.71, and 5.96 eV for sample B, as well as 4.60 and 5.82 eV for sample C. Activation of purebred chicken eggshell powder as antibacterial was performed both qualitatively and quantitatively using photocatalytic and non-photocatalytic methods. Qualitatively, both samples showed antibacterial activity, with a minimal inhibitory concentration (MIC) of 1,000 µg/mL
Land Use Change Mapping and Analysis Using Remote Sensing and GIS: A Case Study in Tam Ky City, Quang Nam Province, Vietnam
No full textChanges in land use/land cover (LULC) play a critical role in effective natural resource management, monitoring, and development, particularly within the realm of urban planning. In the examination of Tam Ky city, Quang Nam province, Vietnam, spanning from 2000 to 2020, remote sensing and Geographic Information System (GIS) techniques were employed. The Landsat satellite data (Landsat 7 ETM+ for 2000, Landsat 5 TM for 2010, and Landsat 8 OLI for 2022) underwent analysis using the supervised classification method in ArcGIS 10.8 software to identify and categorize six primary LULC classes: water bodies, agriculture, settlements, vegetation, construction, and bare soil/rocks. The reliability of the classification was evaluated through k values, revealing high accuracy with values of 0.951, 0.953, and 0.950 for the years 2000, 2010, and 2020, respectively. Notable shifts in LULC were observed during the period from 2000 to 2020. The areas covered by vegetation and settlements expanded by 53 and 1300 ha, respectively, while water bodies, agriculture, construction, and bare soil/rocks experienced reductions of 466, 48, 413, and 425 ha, respectively. To facilitate a rapid assessment, the study also incorporated the normalized difference vegetation index (NDVI) and normalized difference built-up index (NDBI). The trends identified in this study are consistently aligned with the results of the supervised classification. The identified changes in LULC pose a substantial environmental threat, and the study's outcomes serve as a valuable asset for future land use planning and management in the area. The method's high accuracy enhances the dependability of the results, making them crucial for well-informed decision-making and sustainable development initiatives
Characterization of Extracellular Chitinase from Bacillus cereus SAHA 12.13 and Its Potency as a Biocontrol of Curvularia affinis
No full textBacillus cereus SAHA 12.13 can produce chitinase, an enzyme that digests chitin in the main compounds of cell walls, mycelia, and spores in pathogenic fungi that cause leaf spots on oil palm plants such as Curvularia affinis. This study aims to determine the properties of the chitinase enzyme B. cereus SAHA 12.13 that can inhibit the growth of C. affinis. Chitinase enzyme production and characterization were measured using the Spindler method. Antagonism test against pathogenic fungi using dual culture method by testing cell culture and enzyme crude extract. This result showed that the isolate produced a high level of specific chitinase activity at 37 °C for 45 h of incubation with 8.45 U mg-1 proteins with a growth rate (k) of 0.25 generation/h, and the generation time was 3.96 h/generation. The optimum chitinase activity was achieved at pH 7.0 and 45 °C and was stable for 3 h with a half-life (t1/2) of 770 min. The crude enzyme and cell culture of strain can inhibit the growth of C. affinis by 36.27±0.043% and 34.25±0.041%, respectively. These characteristics indicate that B. cereus strain SAHA12.13 can be used to inhibit C. affinis, which causes leaf blight of oil palm, under varying pH and temperature conditions
Green Synthesis of ZnO Nanoparticles using Abelmoschus esculenthus L. Fruit Extract: Antioxidant, Photoprotective, Anti-inflammatory, and Antibacterial Studies
No full textNanoparticles are extensively studied for their promising biological properties. In this study, the fruit extract of Abelmoschus esculenthus L. was used as a chelating agent for the synthesis of zinc oxide nanoparticles (ZnOPs-AE) using a zinc acetate solution. The prepared ZnOPs-AE were identified and characterized using UV-vis spectroscopy, Fourier-transformed infrared spectroscopy (FTIR), particle size analyzer (PSA), scanning electron microscopy (SEM), and energy dispersive spectrum (EDS). The green synthesized ZnOPs-AE were evaluated for their antioxidant, photoprotective, anti-inflammatory, and antibacterial activities. The synthesized nanoparticles showed an intensity peak at 370 nm in the UV-vis spectrum. The FTIR result shows the presence of O-H, C=O, C-O, C-OH, and C=C chelating functional groups on the surface of nanoparticles. The size of ZnOPs-AE was determined using a PSA with particle size distribution of 102.2 nm. The ZnOPs-AE were shown to be spherical by SEM analysis and composition was 82.11% and 14.79% for Zn and O, respectively. The antioxidant properties of ZnOPs-AE showed significant antioxidant potential in DPPH, ABTS, and FRAP assays compared to the quercetin standard. The photoprotection activity test showed a SPF value of 19.63, the percentage of erythema transmission was 5.98%, and the percentage of pigmentation transmission was 5.62%. The ZnOPs-AE showed good anti-inflammatory with the synthesized nanoparticle performing activity between positive control and the fruit extract of Abelmoschus esculenthus L. Also, the ZnOPs-AE exhibited good antibacterial activity against Staphylococcus aureus (20.78 mm) and Pseudomonas aeruginosae (11.13 mm). Overall, the results highlight the effectiveness and potential of ZnOPs-AE for biological application
A Comparative Study on Phytochemical Screening and Antioxidant Activity of Aqueous Extract from Various Parts of Bauhinia purpurea
No full textIn this study, we conducted a comparative investigation into the phytochemical screening and antioxidant activity of aqueous extracts from various parts of the Bauhinia purpurea plant, including leaf, flower, stem bark, and root. The qualitative analysis was performed to screen the phytochemical content of each extract, followed by quantitative analysis to determine the total phenolic and total flavonoid contents. Our findings revealed that different parts of the B. purpureaplant yielded distinct natural products upon extraction. Both the leaf and flower extracts contained alkaloids, flavonoids, saponins, carbohydrates, polyphenols, and phenolics. On the other hand, the aqueous extracts of the stem barks and rootparts of B. purpurea only contained alkaloids, flavonoids, and phenolics. Consistent with the phytochemical assay, the flower extract exhibited the highest total phenolic content (40.14 ± 0.65 µg/mL GAE) and the highest flavonoid content (387.57 ± 0.63 µg/mL CE) compared to the other parts. Consequently, the flower extract displayed the highest antioxidant activity (51.76 ± 0.32%) with DPPH radical assay, closely approaching the antioxidant activity of ascorbic acid (70.54 ± 0.51%), which served as the positive control. This significant finding highlights the potential of the B. purpurea flower as a potent source of antioxidant agents for future applications
Evaluation of The Anticancer Activity of Hydroxyxanthones Against Human Liver Carcinoma Cell Line
No full textNowadays, cancer is one of the most fatal diseases in developed and developing countries. Therefore, it is an urgent need to find more effective anticancer drugs among the recent commercially available standard drugs. Xanthone derivatives have been researched as anticancer drugs due to their ease of synthesis and structure modification, as well as their excellent anticancer activity. In this work, the in vitro anticancer activity of hydroxyxanthones against the human liver carcinoma cell line (HepG2) was evaluated. Among the twenty-two hydroxyxanthones, 1,3,6,8-tetrahydroxyxanthone was found as the most active anticancer agent with an IC50 value of 9.18 μM, which was better than doxorubicin as the standard drug. From the molecular docking studies against topoisomeraseIIα and two c-KIT protein kinases, 1,3,6,8-tetrahydroxyxanthone yielded strong binding energy in a range of -25.48 to -30.42 kJ/mol. The 1,3,6,8-tetrahydroxyxanthone could bind on the active site of these protein receptors through hydrogen bonds with key amino acid residues (Glu640, Cys673, Gln767, Met769, Asp810, and Asp831), as well as nitrogen bases (Adenine12 and Guanine13), thus leading to the death of HepG2 cancer cells through the apoptosis mechanism
Processing of Biodegradable Waste from Ceremonial Activities in Bali with Black Soldier Fly (BSF) Larvae
No full textThe conducted study aimed to analyze the waste processing process from traditional ceremonies in Bali by examining the composition of the waste generated. Since most of the waste generated during these ceremonies is a biodegradable organic material, it is feasible to use sustainable bioconversion techniques such as Black Soldier Fly (BSF) larvae to convert this waste into useful products. In the study, a feeding trial was conducted using a garbage blender consisting of banana fruit, rice, banana leaf, coconut leaf, and flower wastes. The BSF larvae were fed at a rate of 40 mg/larvae per day with a total of 200 larvae. The researchers measured the key processing parameters including overall degradation (OD), waste reduction index (WRI), and feed conversion efficiency (ECD) which resulted in values of 41.27±0.42%, 3.30±0.03 g/day, and 7.82±0.43%, respectively. The study found that the dry residue produced during the process was around 30-31% and met the minimum standards set for compost or biomass fuel. Additionally, the total mass of BSF larvae produced was around 16-18% in one cycle, which is a high protein source that can be used to feed animals