A New Genetic Algorithm for the Maximum Clique Problem

The Maximum Clique Problem is widely studied optimization problem and plays an essential part in computer science. In the literature, therefore, there are many exact and heuristic approaches and new strategies are continuously being proposed. In this paper, the maximum clique problem is studied, and a new hybrid genetic algorithm is proposed for finding the maximum clique in a graph. The proposed algorithm is tested on the DIMACS and BHOSLIB benchmark instances. The computational results are compared with similar literature researches. The results prove the effectiveness of proposed algorithm. © 2020, Springer Nature Switzerland AG

Accelerated Echo Planer J-resolved Spectroscopic Imaging of Putamen and Thalamus in Obstructive Sleep Apnea

Obstructive sleep apnea syndrome (OSAS) leads to neurocognitive and autonomic deficits that are partially mediated by thalamic and putamen pathology. We examined the underlying neurochemistry of those structures using compressed sensing-based 4D echo-planar J-resolved spectroscopic imaging (JRESI), and quantified values with prior knowledge fitting. Bilaterally increased thalamic mI/Cr, putamen Glx/Cr, and Glu/Cr, and bilaterally decreased thalamic and putamen tCho/Cr and GABA/Cr occurred in OSAS vs healthy subjects (p < 0.05). Increased right thalamic Glx/Cr, Glu/Cr, Gln/Cr, Asc/Cr, and decreased GPC/Cr and decreased left thalamic tNAA/Cr, NAA/Cr were detected. The right putamen showed increased mI/Cr and decreased tCho/Cr, and the left, decreased PE/Cr ratio. ROC curve analyses demonstrated 60–100% sensitivity and specificity for the metabolite ratios in differentiating OSAS vs. controls. Positive correlations were found between: left thalamus mI/Cr and baseline oxygen saturation (SaO(2)); right putamen tCho/Cr and apnea hypopnea index; right putamen GABA/Cr and baseline SaO(2); left putamen PE/Cr and baseline SaO(2); and left putamen NAA/Cr and SaO(2) nadir (all p < 0.05). Negative correlations were found between left putamen PE/Cr and SaO(2) nadir. These findings suggest underlying inflammation or glial activation, with greater alterations accompanying lower oxygen saturation. These metabolite levels may provide biomarkers for future neurochemical interventions by pharmacologic or other means