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Optical properties of conducting polymers with Si atoms in main chains, such as optical absorption, photoluminescence (PL), and electroluminescence (EL), have been studied. The electronic energy structures have been determined by optical and electrochemical measurements. The strong PL with high quantum efficiency has been clarified, and spectral narrowing has been observed by pulse excitation of a nitrogen laser. Intense blue or red EL has also been demonstrated and the emission efficiency has been improved by anode surface modification and annealing. [ABSTRACT FROM AUTHOR]

Background: Severely calcified aortic valves are a major limitation of transcatheter aortic valve replacement, because eccentric and heavy calcification of the aortic valve occasionally inhibits self-expansion of the valve frame, resulting in stent under-expansion, including non-uniform expansion or infolding. Nevertheless, the two-dimensional nature of fluoroscopic projection imaging can limit detection of stent under-expansion prior to the final release., Case Summary: We present two cases demonstrating the importance of the steep right anterior oblique (RAO) view (>50°) in detecting significant stent under-expansion of a self-expanding valve prior to the final release. In Case 1, despite enough pre-dilatation, the partially deployed transcatheter heart valve (THV) appeared to be a substantial under-expansion, which was detected only in steep RAO view. Immediately after the final release, the THV was spontaneously embolized into the ascending aorta (the so-called 'pop-up' phenomenon). Emergent implantation of balloon-expandable valve proved to be successful as a bailout. In Case 2, significant stent distortion and infolding, especially on the non-coronary cusp side, was successfully diagnosed only in a steep RAO view prior to the final release. This finding allowed THV recapture and replacement with a new THV., Discussion: Notably, the steep RAO view can visualize the THV from its short axis while eliminating parallax, allowing for accurate diagnosis of THV under-expansion particularly in patients with severe calcification in the non- or right-coronary cusp. Therefore, the steep RAO view allows timely detection of THV under-expansion before the final release, enabling THV recapture and the adoption of several management strategies., Competing Interests: Conflict of interest: D.H. is a clinical proctor for Abbott, Edwards Lifesciences, and Medtronic. All the other authors have no conflict of interest to disclose., (© The Author(s) 2024. Published by Oxford University Press on behalf of the European Society of Cardiology.)

Granular flows of 200 μm particles and the pile formation in a flat-bottomed hopper and bin in the presence of air and in a vacuum were predicted based on three-dimensional numerically empirical constitutive relations using Smoothed Particle Hydrodynamics and Computational Fluid Dynamics methods. The constitutive relations for the strain rate independent stress have been obtained as the functions of the Almansi strain including the large deformation by the same method as Yuu et al. [1]. The constitutive relations cover the elastic and the plastic regions including the flow state and represent the friction mechanism of granular material. We considered the effect of air on the granular flow and pile by the two-way coupling method. The granular flow patterns, the shapes of piles and the granular flow rates in the evolution are compared with experimental data measured under the same conditions. There was good agreement between these results, which suggests that the constitutive relations and the simulation method would be applicable for predicting granular flows and pile formation with complex geometry including free surface geometry. We describe the mechanisms by which the air decreases the granular flow rate and forms the convergence granular flow below the hopper outlet.