Journal Of Natural Sciences And Mathematics Research
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Forecasting the unemployment rate in West Java Province using VARX and SVR methods
Full text linkThis study discusses the forecasting of the Open Unemployment Rate (OUR) in West Java Province using two time series approaches: Vector Autoregressive with Exogenous variables (VARX) and Support Vector Regression (SVR). The dataset consists of monthly observations from 2018 to 2023, including variables such as OUR, the Labor Force Participation Rate (LFPR), Gross Regional Domestic Product (GRDP), and the Human Development Index (HDI). Based on the optimal lag selection using the AIC, the VARX model produced the best lag configuration of (5,2), consisting of five lags for endogenous variables and two for exogenous variables. Meanwhile, the SVR model was developed through Grid Search to find the best parameter combination, resulting in a linear kernel with and . The evaluation results showed that the SVR model performed better than VARX, with MSE, RMSE, and MAPE values of 0.24, 0.49, and 6%, respectively, lower than those of the VARX model, which reached 0.68, 0.82, and 8.4%. SVR was selected as the best model and used to forecast the OUR until the end of 2025. The forecast results indicated a spike in OUR at the beginning of 2024 at 8.52%, followed by a declining trend that continues and stabilizes in the range of 7.96%-8.12% by the end of 2025. In conclusion, SVR outperforms VARX in predictive accuracy, while VARX remains useful for analyzing inter-variable relationships
Morrey spaces in quantum theory: on regularity of the solution of Schrödinger equation via fractional maximal operators
Full text linkIn this paper, we investigate the regularity conditions of solutions of Schrödinger Equations with forcing function in the framework of generalized weighted Morrey spaces. We utilize the established boundedness of the fractional maximal operator on generalized weighted Morrey spaces. We prove that if the forcing function does not balance local regularity and global decay, then the solution of the equation does not do so either
Valorization of Pb 340 rubberwood into liquid smoke as an alternative latex coagulant for Ribbed Smoked Sheet
Full text linkFormic acid, commonly used as a coagulant, has been criticized for its adverse environmental impact, leading to the search for sustainable alternatives. Additionally, the rubber processing industry generates a significant amount of unproductive rubber wood during replanting. A promising path to environmental sustainability is to utilize this potential for liquid smoke production. This study examines the use of liquid smoke from rubber wood Clon PB 340 as a latex coagulant and its effect on RSS quality. The findings indicate that RSS adhered to the P0 standard criteria for all tested liquid smoke concentrations. The 5% liquid smoke introduction to RSS, stored for 7 days, achieved the SRI 5 standard. Additionally, liquid smoke additions effectively managed dirt content, meeting or surpassing control criteria at concentrations of 5%, 20%, and 25%. Although the volatile matter content occasionally met SRI 5 standards at specific concentrations (10%, 15%, 20%, and 25%), the ash content across all treatments, including the control, did not meet the SRI 5 quality benchmarks. Using liquid smoke from non-productive rubber wood Clon PB 340 as a natural coagulant holds promise for eco-friendly latex processing. This study may advance the rubber industry's adoption of liquid smoke, promoting higher-quality, environmentally sustainable products
Evaluation of Paederia foetida L. Extract on Liver Weight Alterations in an Escherichia coli Sepsis Mouse Model
Full text linkSepsis is a critical medical condition caused by a systemic immune response to infection and is often associated with severe organ dysfunction and high mortality. Bacterial sepsis, including cases triggered by Escherichia coli, can damage host tissues as the immune response becomes dysregulated. Infections involving E. coli in the digestive tract have become increasingly common. Among the affected organs, the liver plays a key role in metabolic regulation and host defense during sepsis. This study investigated the effect of Paederia foetida L. leaf extract on liver weight in a murine sepsis model. Introducing E. coli induces systemic infection and establishes the sepsis model, a commonly used approach in experimental studies to mimic the clinical features of sepsis. After acclimation, mice received treatments for 14 days across several groups: a normal control (N), a negative control (K–) given distilled water, a positive control (K+) given ciprofloxacin, and three treatment groups receiving P. foetida extract at 100 mg/kg BW (P1), 300 mg/kg BW (P2), and 500 mg/kg BW (P3). The analysis revealed significant differences among groups, with the highest mean liver weight recorded in P1 (1.3750 ± 0.3932). Liver abnormalities included enlargement, increased organ mass, swelling, and thickening of one liver lobe, which may reflect heightened hepatic workload during infection and toxin clearance. Interestingly, the normal group showed greater liver weight than several treatment groups, possibly due to fatty accumulation within hepatic tissue, which can influence overall organ mass
Simultaneous quantification of B-complex vitamins in tablet dosage form by ultraviolet spectrophotometry using the absorption factor method
Full text linkA novel ultraviolet (UV) spectrophotometric method using the absorption factor approach was developed for the simultaneous quantification of B-complex vitamins (cobalamin, pyridoxine, riboflavin, nicotinamide, and thiamine) in tablet dosage forms. The analysis was carried out using methanol as the solvent, with distinct wavelengths selected for each vitamin: 361 nm for cobalamin, 291 nm for pyridoxine, 269 nm for riboflavin, 262 nm for nicotinamide, and 239 nm for thiamine. The method exhibited excellent accuracy, with recovery rates of 100.0851%, 100.3548%, 100.3322%, 100.7838%, and 100.4271% for cobalamin, pyridoxine, riboflavin, nicotinamide, and thiamine, respectively. This technique provides a simple, precise, and effective means for simultaneous quantification of B-complex vitamins in tablet formulations. The method satisfies all validation criteria and shows minimal interference from excipients, making it a reliable tool for quality control in pharmaceutical analysis
Kombucha origin clustering based on 16S metabarcoding datasets analysis
Full text linkConsumers of fermented products increasingly demand detailed information on product ingredients, quality, health benefits, and origin. Herein, we have chosen kombucha as a model for a fermented product. This study aims to establish the origin information of kombucha using clustering analysis of 16S metabarcoding datasets. We have downloaded and analysed datasets of kombucha 16Smetabarcoding originating from 5 distinct places: Brazil, the United States, the United Kingdom, Turkey, and Thailand. We randomly selected datasets from the collection (n = 32) and analysed them on the SHAMAN server to develop an initial microbiome profile. We implemented hierarchical agglomerative Clustering and found that Ward's method and the Chao distance produced the best cluster tree, which consistently separates kombucha into five distinct clades, reflecting their origin. We have extended our examination to include more datasets (n=13) to build the final cluster tree (total n = 45). We have also assessed the uncertainty of the final Clustering by pvclust in R. The pvclust cluster tree is comparable in topology to the final cluster tree built using Ward's method and Chao distance. The pvclust cluster tree features stable clades that are highly supported by AU (Approximately Unbiased) values (p-value ≥ 95%). Each kombucha was also placed correctly and consistently according to its respective origin. We have successfully conducted analyses and demonstrated that a simple clustering method, combining Ward's method and the Chao distance, is the most effective for classifying kombucha by origin using a 16S metabarcoding dataset
Seismicity analysis of the Southern Java region (2020-2024) based on the b-value and a-value using the maximum Likelihood method
Full text linkThis study investigates the seismicity analysis of the Southern Java region using earthquake data obtained from BMKG Banjarnegara, comprising 1064 events recorded between 2020 and 2024. The study area spans coordinate 7.5°S-8.5°S and 108.31°E-109.50°E. The analysis was conducted using Microsoft Excel, ZMAP 7.0, and QGIS 3.28.2 to calculate the a-value and b-value, key parameters that describe the frequency and magnitude distribution of earthquakes. The magnitude of 2.6 was the most frequently observed, with 150 recorded events, while earthquakes occurring at a depth of 10 km were the most common, totaling 210 events. The high density of seismic occurrences reflects significant tectonic activity in the region. Using the maximum likelihood method, the b-value was determined to be approximately 1.09 ± 0.04, and the a-value was calculated at 5.754. The relatively low b-value suggests areas of elevated stress, implying potential for larger-magnitude earthquakes. Additionally, the spatial distribution of the a-value highlights regions of heightened seismic activity. These findings contribute to a deeper understanding of seismic behavior in Southern Java and offer valuable insights to support disaster risk reduction and earthquake mitigation efforts in the region
Endophytic fungi from Parijoto (Medinilla speciosa) leaves and their potential as biocontrol agents against Corn Pest Larvae
Full text linkParijoto (Medinilla speciosa) leaves are widely used for their antimicrobial properties. Endophytic fungi from these leaves show potential as entomopathogenic agents against Helicoverpa armigera larvae, a moth pest of cotton and corn.The research activities conducted in the laboratory include the isolation and characterization of endophytic fungi, as well as entomopathogenic testing against H. armigera larvae using a spraying technique with endophytic fungal extracts. In this study, 5 isolates were obtained from leaves and assessed their entomopathogenic properties. The isolate code is EP1, EP2, EP3, EP4, EP5. Bioassays were conducted to evaluate the effectiveness of these fungi in controlling H. armigera larvae. Among the tested fungi, EP5 demonstrated the highest entomopathogenic activity, significantly reducing the survival rate of the larvae. These findings indicate that EP5 holds substantial promise as a biocontrol agent for managing H. armigera populations with mortality percentage 30,78%, offering a sustainable and environmentally friendly alternative to chemical pesticides. The study underscores the potential of utilizing endophytic fungi from parijoto leaves in integrated pest management strategies
Comparative study of artificial Neural Network and Kalman Filter models for blood demand forecasting at PMI Surabaya
Full text linkBlood plays a vital role in human health, making the need for donors and transfusions crucial. Currently, the Indonesian Red Cross (PMI) in Surabaya faces a balance issue between blood supply and demand. To address this, a blood demand forecasting model has been created at the PMI using ANN with a 4% error rate. The Kalman Filter algorithm is known to significantly reduce prediction errors from the prediction and correction process, while an ANN is considered capable of handling data complexity and nonlinearity. Therefore, this study aims to analyze the performance of the ANN and Kalman Filter models and compare the model performance results to determine the model with the best performance level. The modelling uses the CRISP-DM method, which starts from data understanding, data preparation, data modelling, model evaluation, and forecasting. The results of this study indicate that the Kalman Filter model successfully minimizes errors compared to the ANN prediction results, achieving a model accuracy level reaching 93.1%. These results demonstrate that the Kalman Filter model can significantly reduce prediction errors in the prediction and correction process, making it more optimal than the ANN model in forecasting blood demand at the PMI in Surabaya
Null Bézier Curves in Minkowski 3-Space
Full text linkIn this paper, we define and investigate the properties of null Bézier curves in Minkowski 3-space. The method applied is a theoretical literature study, applying the definitions of Bézier curves and the geometric framework of null curves in semi-Riemannian geometry. We establish several fundamental characteristics of these curves, including the causal nature of their tangent vectors at endpoints and their Frenet frame apparatus when parametrized by pseudo-arc length. Furthermore, we define the concept of a null Bertrand pair for such curves and prove that if a null Bézier curve of degree n≥3 admits a Bertrand mate, then both curves are necessarily helices. Finally, we provide a conclusive parametric representation of any null Bézier curve in terms of a single non-constant function. This representation offers a powerful tool for explicitly constructing null Bézier curves within this geometric setting