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Influence of Jojoba seed waste and carbon black hybrid filler on styrene butadiene rubber composites characteristics
Abstract This study investigates the effects of jojoba seed waste /carbon black hybrid filler on the mechanical, dielectric, and viscoelastic properties of styrene butadiene rubber composites. The ratios of the seed to carbon black are 0/50, 10/40, 20/30, 30/20, 40/10, and 50/0 phr, respectively. The study evaluates rheometric characteristics and mechanical properties, specifically tensile strength, elongation, and modulus at 100% elongation, both before and after thermo-oxidative aging at 90 °C for various periods of two, four, and six days. Further assessments involved hardness, swelling behavior, crosslink density, and water uptake as well. Moreover, Fourier transform infrared spectroscopy was used to characterize the chemical composition of the samples, while field emission scanning electron microscopy was used to evaluate the surface morphology. The results demonstrate that, increasing the ratio of jojoba seed leads to decreased viscosity and scorch time, improved elongation, and reduced tensile strength, modulus, and hardness. Filler agglomeration alters crosslinking, mechanical characteristics, and aging resistance. Measurements of water uptake demonstrated a positive correlation with seed content, ascribed to the hydrophilic characteristics of the hybrid filler. The dielectric study indicated that increased seed concentration led to a reduction in dielectric permittivity and electrical conductivity, implying enhanced insulating properties. Dynamic mechanical analysis revealed decreases in storage modulus E′ and damping factor tan δ, indicative of enhanced molecular mobility and a reduced glass transition temperature Tg, consistent with increased to the plasticizing influence of residual jojoba oil. In addition, viscosity-related parameters exhibited similar trends, signifying increased flexibility throughout the temperature spectrum. These findings highlight the trade-offs between flexibility and stiffness, allowing composite qualities to be tuned for a wide range of applications.
Multi-criteria assessment of optimization methods for controlling renewable energy sources in distribution systems
Abstract Numerous optimization techniques have recently been employed in the literature to enhance various electric power systems. Optimization algorithms help system operators determine the optimal location and capacity of any renewable energy source (RES) connected to a system, enabling them to achieve a specific goal and improve its performance. This study presents a novel statistical evaluation of 20 famous metaheuristic optimization techniques based on 10 performance measures. The performance measures comprise five power loss indices, three voltage profile indices, load flow calling frequency, and execution time. The evaluation involves 10 distribution systems of varying sizes to ensure an equitable comparison of the algorithm. The Friedman Ranking method evaluates algorithms based on performance metrics, yielding a specific score. Upon modeling all distribution systems, a composite ranking methodology is employed to categorize the algorithms into only four categories: excellent, very good, good, and fair. The study finalizes the ranking of all algorithms according to their overall assessment. The AEO, GWO, JS, PSO, MVO, BO, and GNDO algorithms attain ranks below 25%, thereby placing them in the highest category. The ALO, DA, FPA, SSA, YAYA, and SPO algorithms fall into the second category, with rankings ranging from 25 to 50%. The SMA and CGO algorithms are classified in the third group, with rankings between 50 and 75%. The analysis ultimately reveals that the algorithms CStA, HHO, AOA, GOA, and AOS are positioned in the lowest group, each achieving rankings beyond 75%. As comparison case studies, the proposed algorithms achieved a power loss of 87.164 kW for the 33-bus system, which is less than or equal to the published work. The same result is achieved with the 69-bus system, which has a power loss of 71.644 kW for most of the studied algorithms. Using the appropriate algorithms with distribution systems saves time and effort for the system operator, enhances performance, and increases the usability of optimization algorithms.
CH7450924, a KEAP1-NRF2 interaction inhibitor, ameliorates LPS-induced multiple organ dysfunction via inflammatory pathway inhibition
Elite Bernoulli-based mutated dung beetle algorithm for global complex problems and parameter estimation of solar photovoltaic models
Abstract The Dung Beetle Optimization (DBO) algorithm is a relatively recent metaheuristic known for its simplicity, versatility, and low parameter dependence, making it a valuable tool for solving complex optimization problems. Despite its potential, DBO suffers from limitations such as slow convergence and premature stagnation in local optima. To address these critical issues, this paper introduces a novel enhanced variant named Elite Bernoulli-based Mutated Dung Beetle Optimizer with Local Escaping Operator (EBMLO-DBO), specifically designed to improve the convergence speed, search capability, and robustness of the original DBO algorithm. The motivation for this enhancement stems from DBO’s limited performance in high-dimensional and non-convex problems, where it often fails to maintain an effective balance between exploration and exploitation. The novelty of the proposed EBMLO-DBO lies in the integration of four key strategies tailored to overcome these weaknesses: (i) Bernoulli map-based initialization to enhance population diversity and ensure a better global search foundation; (ii) Morlet Wavelet mutation to introduce adaptive local refinements and help the algorithm escape local optima; (iii) elite guidance to accelerate convergence by directing the population toward high-quality regions; and (iv) a local escaping operator (LEO) to dynamically refine the search process and strengthen exploitation without sacrificing exploration. The performance of EBMLO-DBO is rigorously validated using the CEC2017 and CEC2022 benchmark suites, where it achieves Friedman ranks of 1.83 and 2.7 respectively, consistently surpassing eleven state-of-the-art algorithms including PSO, HHO, WOA, and advanced methods like CMAES and IMODE. In benchmark function optimization, EBMLO-DBO demonstrates superior performance by achieving first rank in 50% of CEC2022 functions and obtaining the lowest average fitness values in 18 out of 29 CEC2017 functions. For photovoltaic parameter estimation applications, EBMLO-DBO exhibits exceptional accuracy with RMSE values of 9.8602E-4 for single diode models, 9.81307E-4 for double diode models, and 2.32066E-3 for PV module models, achieving top performance ranks of 1.45, 1.42, and 1.74, respectively. Statistical analysis using Wilcoxon signed-rank test at significance level $$\alpha =0.05$$ confirms the significant superiority of EBMLO-DBO over all compared algorithms, thereby validating the effectiveness and reliability of the proposed enhancements. Overall, the results state that EBMLO-DBO offers a significantly improved search performance and solution quality compared to the original DBO and related methods, thereby justifying the necessity and effectiveness of the proposed enhancements.
Genomic structural equation modeling identifies shared genetic architecture and novel loci for halitosis
Airborne reflectors for satellite-based quantum entanglement and key distribution
Rhizosphere soil properties may not determine tobacco growth after land consolidation
Volatile compounds formed during heating of asymmetric distigmasterol-modified acylglycerols as indicators of thermo-oxidative degradation
Abstract Phytosterols play a significant role for organisms. They are a component of cell membranes and also have transport functions. They are also important for lower human blood cholesterol levels. The asymmetric distigmasterol-modified acylglycerols (DStA) with oleic and palmitic acid were synthesized as new, more stable derivatives than free phytosterols. The new structure can improve phytosterols solubility in oil. The identification of more stable forms of phytosterols will allow their greater use as a food additive. Assessment of the volatile compounds formed during thermo-oxidative degradation of phytosterols (60 °C and 180 °C), which may affect the flavor of food products, is a rapid and sensitive method for evaluating phytosterol degradation. The GC/MS technique was used for the determination of volatile compounds. The aim of this work was to determine the volatiles formed during storage and thermal degradation of DStA in order to develop a rapid and sensitive system of measuring their degradation. The same compounds were identified for free stigmasterol, its esters with fatty acids, and new DStAs. Eight volatile compounds can act as indicators of sterol degradation during storage and heating. The synthesized 2,3-distigmasterylsuccinoyl-1-oleoyl-sn-glycerol (DStS-O) offered the highest thermo-oxidative stability during storage and thermal processing of all the examined acylglycerols.
Positive influence of long-term growth hormone therapy on circulating stem cells in pediatric patients with growth hormone deficiency
Abstract Very small embryonic/epiblast‐like stem cells (VSELs), present in circulating blood, are small, non-hematopoietic cells that express markers of pluripotent embryonic and primordial germ cells. VSELs are believed to contribute to postnatal tissue and organ regeneration. We report the first long-term observation of VSELs in response to growth hormone (GH) therapy in pediatric patients. Twenty patients aged 5.2–13.4 years with GH-deficiency were monitored periodically during the first year of GH treatment. Eight of these patients were re-examined after eight years of continuous therapy. Selected stem cell populations were analyzed in peripheral blood using flow cytometry. Long-term GH therapy resulted in increased numbers of CD34 + VSELs, while CD133 + VSELs remained comparable to baseline. The increase in VSELs was accompanied by parallel increases in circulating hematopoietic stem cells, mesenchymal stromal cells (MSCs), and endothelial progenitor cells. We observed significant positive correlations between VSELs and MSCs, and between CD34 + VSELs and MSCs with postprandial glucose levels. These data suggest that VSELs are responsive to GH treatment. Long-term GH therapy appears to modulate VSEL populations without causing harm and may even enhance them in GH-deficient patients. Unlike findings in experimental animals, GH therapy in humans did not show adverse effects on lifespan or organ function.