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MMR Meor Mohd Affandi,1,2 Minaketan Tripathy,1,3 Syed Adnan Ali Shah,3,4 ABA Majeed1,3 1Laboratory of Fundamental Pharmaceutics, Faculty of Pharmacy, Universiti Teknologi MARA (UiTM), Bandar Puncak Alam, Selangor, Malaysia; 2DDH Core, Universiti Teknologi MARA (UiTM), Shah Alam, Selangor Darul Ehsan, Malaysia; 3Pharmaceutical and Life Sciences Core, Universiti Teknologi MARA (UiTM), Shah Alam, Selangor Darul Ehsan, Malaysia; 4Atta-ur-Rahman Institute for Natural Products Discovery (AuRIns), Faculty of Pharmacy, Universiti Teknologi MARA (UiTM), Bandar Puncak Alam, Selangor, Malaysia Abstract: We examined the solubility of simvastatin in water in 0.01 mol·dm-3, 0.02 mol·dm-3, 0.04 mol·dm-3, 0.09 mol·dm-3, 0.18 mol·dm-3, 0.36 mol·dm-3, and 0.73 mol·dm-3 arginine (ARG) solutions. The investigated drug is termed the solute, whereas ARG the cosolute. Phase solubility studies illustrated a higher extent of solubility enhancement for simvastatin. The aforementioned system was subjected to conductometric and volumetric measurements at temperatures (T) of 298.15 K, 303.15 K, 308.15 K, and 313.15 K to illustrate the thermodynamics involved and related solute–solvent interactions. The conductance values were used to evaluate the limiting molar conductance and association constants. Thermodynamic parameters (ΔG0, ΔH0, ΔS0, and Es) for the association process of the solute in the aqueous solutions of ARG were calculated. Limiting partial molar volumes and expansibilities were evaluated from the density values. These values are discussed in terms of the solute–solvent and solute–cosolute interactions. Further, these systems were analyzed using ultraviolet–visible analysis, Fourier-transform infrared spectroscopy, and 13C, 1H, and two-dimensional nuclear overhauser effect spectroscopy nuclear magnetic resonance to complement thermophysical explanation. Keywords: simvastatin–arginine complex, solubility, volumetric, conductometric, spectroscopy

Cheng Loong Ngan,1 Mahiran Basri,1,2 Fui Fang Lye,1 Hamid Reza Fard Masoumi,1 Minaketan Tripathy,3,4 Roghayeh Abedi Karjiban,1 Emilia Abdul-Malek1 1Department of Chemistry, Faculty of Science, 2Halal Products Research Institute, Universiti Putra Malaysia, Selangor, Malaysia; 3Laboratory of Fundamentals of Pharmaceutics, Faculty of Pharmacy, Puncak Alam Campus, Universiti Teknologi MARA, Selangor, Malaysia; 4Brain and Neuroscience Communities of Research, Universiti Teknologi MARA, Selangor, Malaysia Abstract: This research aims to formulate and to optimize a nanoemulsion-based formulation containing fullerene, an antioxidant, stabilized by a low amount of mixed surfactants using high shear and the ultrasonic emulsification method for transdermal delivery. Process parameters optimization of fullerene nanoemulsions was done by employing response surface methodology, which involved statistical multivariate analysis. Optimization of independent variables was investigated using experimental design based on Box–Behnken design and central composite rotatable design. An investigation on the effect of the homogenization rate (4,000–5,000 rpm), sonication amplitude (20%–60%), and sonication time (30–150 seconds) on the particle size, ζ-potential, and viscosity of the colloidal systems was conducted. Under the optimum conditions, the central composite rotatable design model suggested the response variables for particle size, ζ-potential, and viscosity of the fullerene nanoemulsion were 152.5 nm, –52.6 mV, and 44.6 pascal seconds, respectively. In contrast, the Box–Behnken design model proposed that preparation under the optimum condition would produce nanoemulsion with particle size, ζ-potential, and viscosity of 148.5 nm, –55.2 mV, and 39.9 pascal seconds, respectively. The suggested process parameters to obtain optimum formulation by both models yielded actual response values similar to the predicted values with residual standard error of

Background: Diabetic foot ulcers (DFUs) are a significant complication of diabetes mellitus, leading to increased morbidity and healthcare costs. This study aims to analyze the clinical and microbiological characteristics of DFUs, treatment strategies, and their outcomes in a tertiary care setting. Methods: A retrospective analysis was conducted on 70 patients with DFUs. Data were collected on demographics, ulcer characteristics, comorbid conditions, treatment approaches, and microbiological profiles. Descriptive statistics and inferential analyses were performed to identify patterns and correlations. Results: The study population had a mean age of 62 years, predominantly presenting with DFUs on the foot. Common comorbidities included uncontrolled diabetes, peripheral neuropathy, and hypertension. Klebsiella and Pseudomonas were the most frequently isolated pathogens. Conservative treatment was the most common approach, but a substantial proportion of patients required surgical intervention. The duration of the ulcers varied, with a notable correlation between prolonged healing times and the presence of comorbid conditions. Conclusion: DFUs present a complex challenge requiring a multifaceted approach. Early intervention, optimal glycemic control, and tailored treatment strategies are essential for improving outcomes. Addressing underlying comorbidities is crucial for effective management and prevention of complications. [ABSTRACT FROM AUTHOR]

A new approach to designing a fractional bandpass filter using switched-fractional capacitors has been reported for the first time. This is achieved using four fractional-capacitors $ (F{C_1},\textrm{ }F{C_2},F{C_3},\textrm{ and }F{C_4}) $ (F C 1 , F C 2 , F C 3 , and F C 4) with orders α, β, δ, and λ, respectively, where $ 0 \lt \alpha , \beta , \delta , \lambda \le 1 $ 0 < α , β , δ , λ ≤ 1. The presented work deals with designing a fractional bandpass filter using switched capacitors and switched-fractional capacitors in place of resistors. The stability and the speed of response of the proposed filter have been investigated by computing the filter parameters analytically. Filter parameters such as settling-time ( $ {t_s} $ t s ), peak-overshoot ( $ {M_p} $ M p ), and rise-time ( $ {t_r} $ t r ) improve compared with their integer-order counterpart. Furthermore, detailed comparative studies on different design parameters have also been carried out through simulation studies and experimentations. The particle swarm optimization (PSO) technique is used for getting the optimal values of the orders of the switched-fractional capacitors to improve the response of the proposed filter. [ABSTRACT FROM AUTHOR]

Fractional-order circuits are the emerging area for analyzing the parametric response of the filters and its performance improvement can be analytically observed by using an optimization technique. In this paper, the fractional-order band-pass filter, using fractional-order capacitor (FC) and fractional-order inductor (FI), is investigated. The characteristics of the filter with desired fractional-order of FC and FI bearing range from 0.1 ≤ α ≤ 1.0 to 0.1 ≤ β ≤ 1.0, respectively having a step change of 0.1, are simulated. The frequency parameters of the proposed band-pass filter having order with in this range of α and β resulted during simulation. The quality factor is optimized from the results of the fractional-orders α and β for the given FC and FI, respectively. The theoretical quality factor in this integer-order filter is compared with its optimized Q value in its fractional-order counterpart. The proposed filter is modeled by using the best orders of α = 0.4 and β = 1.0 for FC and FI, respectively with optimized Q-factor. Finally, the frequency parameters of the filter as modeled are obtained through simulation using MATLAB/Simulink R2011a. [ABSTRACT FROM AUTHOR]

Optimal location and control of a unified power flow controller (UPFC) along with transformer taps are tuned with a view to simultaneously optimize the real power losses and voltage stability limit (VSL) of a mesh power network. This issue is formulated as a nonlinear equality and inequality constrained optimization problem with an objective function incorporating both the real power loss and VSL. A new evolutionary algorithm known as bacteria foraging is applied for solving the multiobjective multivariable problem, with the UPFC location, its series injected voltage, and the transformer tap positions as the variables. For a single objective of only real power loss, the same problem is also solved with interior point successive linearization program (IPSLP) technique using the LINPROG command of MATLAB. A comparison between the two suggests the superiority of the proposed algorithm. A cost effectiveness analysis of UPFC installation vis-a-vis loss reduction is carried out to establish the benefit of investment in a UPFC. Index Terms--Bacteria foraging, continuation power flow, linear programming, optimal power flow (OPF).

An integrated approach of radial basis function neural network (RBFNN) and Takagi-Sugeno (TS) fuzzy scheme with a genetic optimization of their parameters has been developed in this paper to design intelligent adaptive controllers for improving the transient stability performance of power systems. At the outset, this concept is applied to a simple device such as thyristor-controlled series capacitor (TCSC) connected in a single-machine infinite bus power system and is then extended to interline power-flow controller (IPFC) connected in a multimachine power system. The RBFNN uses single neuron architecture and its parameters are dynamically updated in an online fashion with TS-fuzzy scheme designed with only four rules and triangular membership function. The rules of the TS-fuzzy scheme are derived from the real- or reactive-power error and their derivatives either at the TCSC or IPFC buses depending on the device. Further, to implement this combined scheme only one coefficient in the TS-fuzzy rules needs to be optimized. The optimization of this coefficient as well as the coefficient for auxiliary signal generation is performed through genetic algorithm. The performance of the new controller is evaluated in single-machine and multimachine power systems subjected to various transient disturbances. The new genetic-neuro-fuzzy control scheme exhibits a superior damping performance as well as a greater critical clearing time in comparison to the existing PI and RBFNN controller with updating of its parameters through the extended Kalman filter (EKF). Its simple architecture reduces the computational burden, thereby making it attractive for real-time implementation. Index Terms--Damping modal oscillations, FACTS, fuzzy, genetic, intelligent controller, neural, power system, stability.