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Over the past decade, law enforcement organizations have been dealing with the development of cybercrime. To address this growing problem, law enforcement organizations apply various digital forensic (DF) tools and techniques to investigate crimes involving digital devices. This ensures that evidence is admissible in legal proceedings. Consequently, DF analysts may need to invest more in proprietary DF hardware and software to maintain the viability of the DF lab, which will burden budget-constrained organizations. As an alternative, the open source DF tool is considered a cost-saving option. However, the admissibility of digital evidence obtained from these tools has yet to be tested in courts, especially in Malaysia. Therefore, this study aimed to explore the admissibility of digital evidence obtained through open source DF tools. By reviewing the existing literature, the factors that affect the admissibility of the evidence produced by these tools in courts were identified. Further, based on the findings, a conceptual framework was developed to ensure the admissibility of the evidence so that it will be accepted in the court of law. This conceptual framework was formed to outline the factors affecting the admissibility of digital evidence from open source DF tools, which include; 1) The Availability and Capability of open source DF tools, 2) the Reliability and Integrity of the digital evidence obtained from open source DF tools, 3) the Transparency of the open source DF tools, and 4) the Lack of Reference and Standard of open source DF tools. This study provides valuable insights into the digital forensic field, and the conceptual framework can be used to integrate open source DF tools into digital forensic investigations. [ABSTRACT FROM AUTHOR]

The nonlinear system of equations (NSE) is the basis of many engineering and scientific models. However, these models must have accurate solutions to be successful. Several optimization algorithms, including Butterfly Optimization Algorithm (BOA), can be applied to solving NSE problems. However, optimization algorithms lack accurate solutions due to their limitations, including trapping at local optima and divergence problems. In this work, a novel hybrid approach that is called Jarratt Butterfly Optimization Algorithm (JBOA) is presented to solve NSE. The proposed JBOA is developed by combining Jarratt's iterative method and the BOA. Combining the two methods has enhanced BOA's search mechanism and convergence speed. It also overcomes Jarratt's limitations, including selecting initial values, trapping at local optima, and divergence problems. This results in solving NSE in more accurate solutions and fewer iterations. JBOA's efficiency was evaluated based on eight benchmark systems, two of which represent real-world applications. Further, JBOA was compared to several optimization algorithms, including the original BOA algorithm, Particle Swarm Optimization (PSO), Harris Hawk Optimization (HHO), Equilibrium Optimization (EO), and Ant Lion Optimizer (ALO). Furthermore, the performance of JBOA and Jarratt's method has been compared. Finally, the experimental results support the superiority of JBOA as it significantly outperformed all other compared optimization algorithms in all benchmark systems in terms of best solutions, average fitness values, stability, and convergence speed. [ABSTRACT FROM AUTHOR]

Abstract: The resistance status towards permethrin among the laboratory strain, the permethrin-selected strain and four field strains of Culex quinquefasciatus collected in Kuala Lumpur, Malaysia was determined using three standard laboratory methods: WHO larval bioassay, WHO adult bioassay and biochemical microplate assay. Cx. quinquefasciatus permethrin-selected strain larvae were the least susceptible to permethrin with a resistance ratio of 47.28-folds, whereas all field strain larvae of the same species were tolerant to permethrin with resistance ratios of more than 3-folds. In contrast, in adult stage, the permethrin exposed permethrin-selected strain (resistance ratio=1.27) was found to be more susceptible to permethrin than all permethrin-exposed field strains (resistance ratios=2.23–2.48). Complete mortalities for all strains of Cx. quinquefasciatus adults proved the effectiveness of the synergist; piperonyl butoxide (PBO). For the biochemical microplate assay, the reduction of the mean optical density of elevated oxidase activity of three field strains upon exposure to PBO confirmed the association between oxidase activity and permethrin tolerance. On the other hand, irregular patterns of the mean optical density of elevated oxidase activity in the laboratory strain, permethrin-selected strain and Jalan Fletcher strain illustrated the gene variation within these mosquito colonies as well as the involvement of other enzyme activities in the permethrin resistance occurred. [Copyright &y& Elsevier]

Abstract: Permethrin resistance status of a laboratory strain, a permethrin-selected strain and three field strains of Aedes aegypti collected in Kuala Lumpur, Malaysia were evaluated using three standard laboratory bioassays: WHO larval bioassay, WHO adult mosquito bioassay, and mixed function oxidase (MFO) enzyme microassay. The LC50 values of field strains from the WHO larval bioassay did not differ significantly. The highest LC50 value was from the Taman Melati field strain (0.39mg/L). The resistance ratio for the permethrin-selected strain and the field strains ranged from 1.86 fold to 5.57 fold. Pre-exposure to piperonyl butoxide (PBO) in the WHO adult bioassay and MFOs enzyme microassay reduced the LT50 values and reduced the mean optical density of elevated oxidase activity (0.28–0.42) at 630nm. The LC50 or LT50 values and the level of oxidases were significantly correlated (r =0.825; p<0.05). This study confirmed the presence of permethrin resistance in these mosquito populations. [Copyright &y& Elsevier]