The aim of this paper is to give a description of Lie derivations of generalized matrix algebras. As a consequence Lie derivations of full matrix algebras are determined.

Optical computed tomography (optical-CT) is a high-resolution, fast, and easily accessible readout modality for gel dosimeters. This paper evaluates a hybrid iterative image reconstruction algorithm for optical-CT gel dosimeter imaging, namely, the simultaneous algebraic reconstruction technique (SART) integrated with ordered subsets (OS) iteration and total variation (TV) minimization regularization. The mathematical theory and implementation workflow of the algorithm are detailed. Experiments on two different optical-CT scanners were performed for cross-platform validation. For algorithm evaluation, the iterative convergence is first shown, and peak-to-noise-ratio (PNR) and contrast-to-noise ratio (CNR) results are given with the cone-beam filtered backprojection (FDK) algorithm and the FDK results followed by median filtering (mFDK) as reference. The effect on spatial gradients and reconstruction artefacts is also investigated. The PNR curve illustrates that the results of SART  +  OS  +  TV finally converges to that of FDK but with less noise, which implies that the dose-OD calibration method for FDK is also applicable to the proposed algorithm. The CNR in selected regions-of-interest (ROIs) of SART  +  OS  +  TV results is almost double that of FDK and 50% higher than that of mFDK. The artefacts in SART  +  OS  +  TV results are still visible, but have been much suppressed with little spatial gradient loss. Based on the assessment, we can conclude that this hybrid SART  +  OS  +  TV algorithm outperforms both FDK and mFDK in denoising, preserving spatial dose gradients and reducing artefacts, and its effectiveness and efficiency are platform independent.

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A passively Q-switched Tm,Ho:GdVO4 laser operating at cryogenic temperature with a Cr(2+):ZnS saturable absorber pumped with continuous wave LDs was demonstrated. The performance of the laser was investigated through changing the distance between Cr(2+):ZnS and output coupler. The maximum pulse energy of 70.5 μJ was obtained at 10 W input power. The maximum average output power of PQS laser was up to 3.2 W at the pump power of 22.8 W, corresponding to CW output power of 7.4 W, pulse repetition frequency of 52 kHz, and a pulse width of 389 ns. The M(2) factor measured by the traveling knife-edge method was ~1.1 in x and y directions with near-diffraction limited beam quality.

A novel temperature sensor based on a Teflon capillary encapsulated 2 × 2 optical microfiber coupler (OMC) filled with refractive index matching liquids is described. The sealed capillary and the filling liquid are demonstrated to enhance the temperature sensing performance, achieving a high temperature sensitivity of 5.3 nm/°C. To the best of our knowledge, the temperature sensor described in this article exhibits the highest sensitivity among the OMC structure based fiber optic temperature sensors. Experimental results also show that it has good repeatability along with a fast response time of 243 ms. 21(11), 461-462 (1985). 21. R. X. Gao, Q. Wang, F. Zhao, B. Meng, and S. L. Qu, "Optimal design and fabrication of SMS fiber temperature sensor for liquid," Opt. Commun. 283(16), 3149-3152 (2010). 22. Y. Chen, Q. Han, T. Liu, and X. Lü, "Self-temperature-compensative refractometer based on singlemodemultimode-singlemode fiber structure," Sens. Actuators B Chem. 212, 107-111 (2015).