Reducing negative effects of quadratic norm regularization on image reconstruction in electrical impedance tomography

Employing the conventional quadratic norm to regularize the inverse problem in electrical impedance tomography often stabilizes the solution at the expense of imposing some smoothness on the reconstructed image. This study proposes a novel multi-regularized approach in order for quadratic norm regularization to reduce its deleterious effects on the reconstructed image. The amounts of regularization exerted on the finite elements over the mesh are not kept constant, but are changed depending on either the sensitivity of the boundary measurements to the finite elements, or the anomaly positioning. The results show that the proposed schemes appreciably improve the image with regard to spatial resolution, artifact, and shape preservation. These schemes considerably reduce the unappealing sensitivity of the inverse solution to the regularization parameter changes as well.     

Identification of volatile organic compounds in flowers of Astragalus lagopoides

Composition of volatile organic compounds (VOCs) in flowers of Astragalus lagopoides was studied using a hydrodistillation extraction procedure coupled with gas chromatography-mass spectrometry. The analyses allowed the identification of a number of 25 compounds, among which the presence of several bioactive aromatic derivatives such as guaiacol, eugenol, linalool, α- and 4-terpineol as well as nerol was attention-grabbing. Moreover, some other compounds like cyclohexane, 2-bromoethyl with repellent function also appeared to be present in the flower. As a result, the floral VOCs profile of A. lagopoides might reflect an adaptation to attract specialised pollinator insects. These findings provide important information for advances in understanding the ecological and evolutionary perspectives of pollination biology of the giant genus Astragalus.     

Toxicity of copper oxide nanoparticles on Spirodela polyrrhiza: assessing physiological parameters

Research on Chemical Intermediates - The surface characteristics of nanoparticles cause their influx into the environment and lead to their interaction with fungi, algae, and plants. In the present...