Journal of Mathematical and Fundamental Sciences
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Synthesis of Human Antibodies Against HBsAg in Newly Established Chinese Hamster Lung (CHL-YN) Cell Line
Full text linkHepatitis B immunoglobulin (HBIG) is an effective treatment for hepatitis B, including postexposure prophylaxis of HBV infection, prevention of HBV reinfection in liver transplant patients, and reducing sexual transmission. This study investigated the synthesis of human IgG antibodies that specifically target HBsAg subtype adr in CHL-YN cells, a newly established cell line that grows faster than CHO-K1. To achieve the synthesis of human IgG antibodies, a plasmid vector encoding DNA sequences for human IgG antibodies against HBsAg was constructed and then transiently transfected into CHL-YN cells. The expression and antigen-binding capacity of the recombinant human IgG antibodies were analyzed using western blot and ELISA. The results showed successful expression and secretion of human IgG antibodies that recognize HBsAg subtype adr in CHL-YN cells. The ELISA test confirmed the specificity of the human IgG antibodies towards HBsAg subtype adr. Thus, this study concluded that human IgG antibodies that target HBsAg subtype adr were transiently expressed in CHL-YN cells
Backward Bifurcation Emerging from a Mathematical Model of African Animal Trypanosomiasis Disease in White Rhino Populations
Full text linkThis paper introduces a mathematical model for African animal trypanosomiasis (AAT) in white rhino and tsetse fly populations. The model accommodates two types of interventions, namely infection detection and ground spraying. The dynamical system properties were thoroughly investigated to show the existence of equilibrium points, backward bifurcation, and how they are related to the basic reproduction number. We found that there is a chance that AAT may die out from the population if the basic reproduction number is smaller than one. However, the possible existence of backward bifurcation implies a condition where we may have a stable endemic equilibrium, even when the basic reproduction number is smaller than one. Hence, the basic reproduction number is no longer sufficient to guarantee the disappearance of AAT from the population. Our sensitivity analysis on the basic reproduction number showed that the interventions of infection detection and ground spraying have good potential to eradicate AAT from the population. To analyze the most effective intervention as time-dependent variable, we reconstructed our model as an optimal control problem. Numerical simulations on various scenarios were conducted for the optimal control problem. Cost-effectiveness analysis using the Average Cost-Effectiveness Ratio (ACER) and the Incremental Cost-Effectiveness Ratio (ICER) methods was performed. From the cost-effectiveness analysis, we found that ground spraying is the most cost-effective intervention to combat the spread of AAT in white rhino populations
Piper crocatum Ameliorates APAP-Induced Hepatotoxicity through Antioxidant and Anti-Inflammatory Mechanisms
Full text linkCirrhosis is a serious hepatic disease that occurs worldwide and is caused by progressive fibrosis in the liver. Free radicals are the major cause of reactive oxygen species (ROS) generation, which affects the balance of the liver metabolism. Piper crocatum, commonly called red betel, is widely used in ethnomedicine because it has biological capabilities, including antioxidant and anti-inflammatory properties. The present study was undertaken to examine the possibility of hepaprotective activity of red betel extract on acetaminophen (APAP)-induced HepG2 cells as the cirrhosis in vitro model. Assessment of red betel extract (RBE) was performed using the colorimetric method for the quantification of LDH, AST, and ALT. As preliminary study, a cytotoxicity assay was performed at various RBE concentrations (100.00; 50.00; 25.00; 12.50; 6.25; 3.13 μg/ml) using an MTS assay to decide the safe concentration based on cell viability. The RBE treatment did not affect cell viability, even at a high concentration (100 µg/ml, p > 0.05). RBE at concentrations 25 and 100 µg/ml successfully reduced LDH, AST, and ALT activities in the hepatotoxic model in a dose-dependent manner. In the APAP-induced hepatotoxicity model, RBE positively indicated a hepatoprotective effect and cell amelioration by a decrease in hepatotoxic markers
Cluster Analysis on Dengue Incidence and Weather Data Using K-Medoids and Fuzzy C-Means Clustering Algorithms (Case Study: Spread of Dengue in the DKI Jakarta Province)
Full text linkIn Indonesia, Dengue incidence tends to increase every year but has been fluctuating in recent years. The potential for Dengue outbreaks in DKI Jakarta, the capital city, deserves serious attention. Weather factors are suspected of being associated with the incidence of Dengue in Indonesia. This research used weather and Dengue incidence data for five regions of DKI Jakarta, Indonesia, from December 30, 2008, to January 2, 2017. The study used a clustering approach on time-series and non-time-series data using K-Medoids and Fuzzy C-Means Clustering. The clustering results for the non-time-series data showed a positive correlation between the number of Dengue incidents and both average relative humidity and amount of rainfall. However, Dengue incidence and average temperature were negatively correlated. Moreover, the clustering implementation on the time-series data showed that rainfall patterns most closely resembled those of Dengue incidence. Therefore, rainfall can be used to estimate Dengue incidence. Both results suggest that the government could utilize weather data to predict possible spikes in DHF incidence, especially when entering the rainy season and alert the public to greater probability of a Dengue outbreak
Ficus elastica Leaf Extract Effect Toward IL-10 and TNF-α as a Preeclampsia Model on Hypoxia-induced EA.hy926
Full text linkPreeclampsia is a pregnancy complication characterized by proteinuria, hypertension, hypoxia as well an increased systemic inflammatory response. It affects 5 to 10% of all births and is a leading factor in fetal and maternal morbidity and death. Ficus elastica L. leaves are known to have natural compounds with anti-inflammatory and antioxidant properties. This research assessed the potential of F. elastica leaf extract (FEE) as anti-inflammatory agent in a hypoxic-induced human endothelial cell line (EA.hy926) as preeclampsia model. F. elastica leaves were extracted using 70% ethanol. Cytotoxic assay of the FEE in different concentrations (3.13 to 100 µg/ml) against EA.hy926 was done using MTS assay. The FEE’s anti-inflammatory activity was measured with ELISA for the TNF-α and IL-10 parameters. The FEE did not cause cytotoxicity to the EA.hy926 cells, with viability above 80% at the highest concentration. The FEE could decrease the pro-inflammatory TNF-α level and increase the IL-10 level as anti-inflammatory markers in the preeclampsia model at significance level p < 0.05. This study suggests that FEE is a safe alternative herbal medicine for preeclampsia treatment
Flower Pollination and Elitism Algorithms for Inversion of TDEM Data
Full text linkHybridization of algorithms can enhance the overall search capabilities to get the optimal solution. The aim of this study was to invert Time Domain Electromagnetic (TDEM) data using the Flower Pollination Algorithm (FPA) as a new inversion scheme technique. FPA was originally inspired by the fertilization process of flowers, in which pollen transfer grains from male flowers to female flowers. The modeling of TDEM data was done by combining the FPA and elitism (eFPA) techniques. The applicability was tested on forward modeling data and observed data in MATLAB 2017a. In testing the algorithm, we used a model from homogeneous half space to a multi-layer model using different parameters (resistivity and thickness). In addition, in the inversion process, we used field data with various starting model approaches. Based on the results of the TDEM data modeling, FPA and eFPA can both be applied as algorithmic techniques for inversion modeling of TDEM data. The eFPA technique gave better results than FPA
Oxygen Reduction Reaction Mechanism on the Square Paddle-Wheel Cage Site of TM-BTC (TM=Mn, Fe, Cu) Metal-Organic Framework
Full text linkOur study examined the mechanism of oxygen reduction reactions (ORR) at the square paddle-wheel cage active site of TM-BTC metal-organic frameworks (MOFs), where TM is a transition metal, Mn, Fe, or Cu. We used a combination of density functional theory (DFT) and microkinetic calculations to investigate this mechanism. By using a small cluster for modeling the TM-BTC active site structure, we successfully reproduced the experimental trend of ORR activity in the TM-BTC systems: Mn-BTC > Fe-BTC > Cu-BTC. We also found that the unusual ORR activity trend in experiments for Mn and Fe systems originates from the strength of OH adsorption on these systems. The Mn-BTC system exhibits higher ORR activity than the Fe-BTC system due to its weaker adsorption of OH groups. A very strong OH adsorption makes the final OH reduction step sluggish, hence hindering the ORR process
Prediction of Carbon Monoxide Concentration with Variation of Support Vector Regression Kernel Parameter Value
Full text linkHuman and industrial activities produce air pollutants that can cause a decline in air quality. In urban areas, transportation activities are the main source of air pollution. One of the emitted air pollutants produced by transportation is carbon monoxide (CO). The understanding of CO concentration is crucial since its overabundance beyond a certain limit will have a negative impact on human health and the environment. In this study, the support vector regression (SVR) method was used to predict CO concentration. The purpose of this study was to predict the hourly CO concentration in the Ujung Berung district, Bandung City, West Java, Indonesia with optimal prediction accuracy. An experiment was carried out by modeling the CO concentration with varying kernel parameter values to obtain accurate prediction results. The suitability of the values between error (ɛ), a trade-off constant (C), and variation mismatch (γ) is vital to obtain optimal prediction results. The results showed that the best prediction accuracy value was 97.68% with kernel parameter values ɛ = 0.02, γ = 30, and C = 0.006. These results may lead to proper decision making on environmental issues and can improve air pollution control strategies
Dielectric Meta-lattices with Tunable Reflectivity
Full text linkWe report a study on the reflective performance of a dielectric meta-lattice formed by a one-dimensional periodic arrangement of silicon nanotubes. It was found that switching from transparent state to reflective state can be done by simply varying one optical parameter of the meta-lattice. The meta-lattice was shown to be capable of providing near-zero and near-unity reflectance at any desired wavelength, even in oblique incidence cases. The results are thus very promising for the development of future optical devices