Enhancing engineering optimization using hybrid sine cosine algorithm with Roulette wheel selection and opposition-based learning.

Meta-heuristic algorithms distinguish themselves from conventional optimization methods owing to their intrinsic adaptability and straightforward implementation. Among them, the sine cosine algorithm (SCA) is lauded for its ability to transition seamlessly between exploration and exploitation phases throughout the optimization process. However, there exists potential for enhancing the balance that SCA maintains between exploration and exploitation. To augment the proficiency in global optimization of SCA, an innovative strategy-nSCA-that integrates the roulette wheel selection (RWS) with opposition-based learning was formulated. The robustness of nSCA was rigorously evaluated against leading-edge methods such as the genetic algorithm (GA), particle swarm optimization, moth-flame optimization, ant lion optimization, and multi-verse optimizer, as well as the foundational SCA. This evaluation included benchmarks set by both CEC 2019 and CEC 2021 test functions. Additionally, the performance of nSCA was confirmed through numerous practical optimization problems, emphasizing its effectiveness in applied settings. In all evaluations, nSCA consistently showcased superior performance compared to its evolutionary algorithm counterparts, delivering top-tier solutions for both benchmark functions and real-world optimization challenges. Given this compelling evidence, one can posit that nSCA serves as a strong candidate for addressing intricate optimization challenges found in real-world contexts, regardless of whether they are of a discrete or continuous nature.

Hybrid whale optimization algorithm for enhanced routing of limited capacity vehicles in supply chain management.

The present study focuses on the problem of vehicle routing with limited capacity, with the objective of minimizing the transportation distance required to serve h clients with predetermined locations and needs. The aim is to create k trips that cover the shortest possible distance. To achieve this goal, a hybrid whale optimization algorithm (hGWOA) is proposed, which combines the whale optimization algorithm (WOA) with the grey wolf optimizer (GWO). The proposed hybrid model is comprised of two main steps. First step, the GWO's hunting mechanism is integrated transitioning to the utilization phase of WOA, and a newly devised state is introduced that is linked to GWO. In the second step, a novel technique is incorporated into the exploration mission phase to enhance the resolve after per iteration. The algorithm's performance is assessed and compared with other modern algorithms, including the GWO, WOA, ant lion optimizer (ALO), and dragonfly algorithm (DA) using 23 benchmark test functions and CEC2017 benchmark test function. The results indicate that the hybrid hGWOA method outperforms other algorithms in terms of delivery distance optimization for scenarios involving scale and complexity. These findings are corroborated through case studies related to cement delivery and a real-world scenario in Viet Nam.

Video-assisted thoracoscopic surgery for myasthenia gravis with thymoma: A six-year single-center experience.

OBJECTIVES: To investigate clinical and histopathological characteristics of Vietnamese patients with thymoma and myasthenia gravis (MG), and the outcomes of surgical management using video-assisted thoracoscopic surgery (VATS) thymectomy. METHODS: A prospective study was carried out on 61 patients undergoing VATS thymectomy for MG class I, IIA with thymoma in the period from 10/2013 to 5/2019. The WHO histopathological classification, Masaoka's stages and MG grading using the guidelines of the Medical Scientific Advisory Board of the Myasthenia gravis foundation of America (MGFA) were used. All patients were followed up at 1 month, 6 months and over 1 year postoperatively. RESULTS: The average patient age was 47.3 ± 10.8 years (21-70). The female/male ratio was 0.91.80.3% of patients had MG class IIA. Most of the patients were at Masaoka's stage I and stage II (75.4%). Only 1 patient (1.7%) had highly malignant type B3 thymoma. Conversion to open surgery was required in 8 patients. The surgical time was 91.8 ± 49.9 min and blood loss was 37.3 ± 31.5 ml. Most patients (68.9%) were extubated in the operating room. The postoperative hospital stay was 9.8 ± 5.9 days (5-37 days). 22.6% of patients relapsed after one-year. Refractory MG declined to 5.7% after surgical treatment. CONCLUSION: VATS thymectomy for MG with thymoma was safe and effective, with a lower rate of intraoperative complications, shorter hospitalization, and better long-term outcomes. This approach could be applicable for patients of all age groups with thymomas at early Masaoka's stages.

Purification and characterization of chitinases from Paecilomyces variotii DG-3 parasitizing on Meloidogyne incognita eggs.

Two extracellular chitinases were purified from Paecilomyces variotii DG-3, a chitinase producer and a nematode egg-parasitic fungus, to homogeneity by DEAE Sephadex A-50 and Sephadex G-100 chromatography. The purified enzymes were a monomer with an apparent molecular mass of 32 kDa (Chi32) and 46 kDa (Chi46), respectively, and showed chitinase activity bands with 0.01% glycol chitin as a substrate after SDS-PAGE. The first 20 and 15 N-terminal amino acid sequences of Chi32 and Chi46 were determined to be Asp-Pro-Typ-Gln-Thr-Asn-Val-Val-Tyr-Thr-Gly-Gln-Asp-Phe-Val-Ser-Pro-Asp-Leu-Phe and Asp-Ala-X-X-Tyr-Arg-Ser-Val-Ala-Tyr-Phe-Val-Asn-Trp-Ala, respectively. Optimal temperature and pH of the Chi32 and Chi46 were found to be both 60 degrees C, and 2.5 and 3.0, respectively. Chi32 was almost inhibited by metal ions Ag(+) and Hg(2+) while Chi46 by Hg(2+) and Pb(2+) at a 10 mM concentration but both enzymes were enhanced by 1 mM concentration of Co(2+). On analyzing the hydrolyzates of chitin oligomers [(GlcNAc)( n ), n = 2-6)], it was considered that Chi32 degraded chitin oligomers as an exo-type chitinase while Chi46 as an endo-type chitinase.

Enzymatic deacetylation of chitin by extracellular chitin deacetylase from a newly screened Mortierella sp. DY-52.

Among more than a hundred colonies of fungi isolated from soil samples, DY-52 has been screened as an extracellular chitin deacetylase (CDA) producer. The isolate was further identified as Mortierella sp., based on the morphological properties and the nucleotide sequence of its 18S rRNA gene. The fungus exhibited maximal growth in yeast peptone glucose (YPD) liquid medium containing 2% of glucose at pH 5.0 and 28 degrees C with 150 rpm. The CDA activity of DY-52 was maximal (20 U/mg) on the 3rd day of culture in the same medium. The CDA was inducible by addition of glucose and chitin. The enzyme contained two isoforms of molecular mass 50 kDa and 59 kDa. This enzyme showed a maximal activity at pH 5.5 and 60 degrees C. In addition, it had a pH stability range of 4.5-8.0 and a temperature stability range of 4-40 degrees C. The enzyme was enhanced in the presence of Co2+ and Ca2+. Among various substrates tested, WSCT-50 (water-soluble chitin, degree of deacetylation 50%), glycol chitin, and crab chitosan (DD 71-88%) were deacetylated. Moreover, the CDA can handle N-acetylglucosamine oligomers (GlcNAc)2-7.