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We report on a cascade nanosecond CdSe optical parametric oscillator with an output energy of 0.54 mJ at 100 Hz, temperature tuning within 9245–9285 nm, and a narrow (∼6 cm−1) spectral width achieved by a volume Bragg grating acting on the first stage. The CdSe crystal is pumped intracavity by the signal wave from the PPKTP-based first stage, and both stages operate under noncritical phase-matching conditions. The simple, compact, and robust setup produced the highest overall conversion efficiency for an all-solid-state laser system based on CdSe with 1-μm pumping, and the corresponding quantum conversion efficiency exceeded 13%. [ABSTRACT FROM AUTHOR]

Traditional differential expression genes (DEGs) identification models have limitations in small sample size datasets because they require meeting distribution assumptions, otherwise resulting high false positive/negative rates due to sample variation. In contrast, tabular data model based on deep learning (DL) frameworks do not need to consider the data distribution types and sample variation. However, applying DL to RNA-Seq data is still a challenge due to the lack of proper labeling and the small sample size compared to the number of genes. Data augmentation (DA) extracts data features using different methods and procedures, which can significantly increase complementary pseudo-values from limited data without significant additional cost. Based on this, we combine DA and DL framework-based tabular data model, propose a model TabDEG, to predict DEGs and their up-regulation/down-regulation directions from gene expression data obtained from the Cancer Genome Atlas database. Compared to five counterpart methods, TabDEG has high sensitivity and low misclassification rates. Experiment shows that TabDEG is robust and effective in enhancing data features to facilitate classification of high-dimensional small sample size datasets and validates that TabDEG-predicted DEGs are mapped to important gene ontology terms and pathways associated with cancer. [ABSTRACT FROM AUTHOR]

The Dy3+:PbGa2S4 crystal with low phonon energy has been used to achieve direct lasing of 4.3–4.7 μm lasers. High quality PbGa2S4 crystals are difficult to fabricate due to component volatilization. In this work, the influence of component condition on the intrinsic defects and optical absorption in the Dy3+:PbGa2S4 crystal was investigated through first-principles calculations and crystal growth experiments. We found that PbGa2S4 was prone to decompose into Ga2S3 at its growth temperature, usually resulting in PbS-rich (Ga2S3-deficient) growth conditions. The calculated results of defect formation energy indicate that the PbGa and VGa defects play a dominant role in PbGa2S4 under PbS-rich growth conditions. The Ga2S3-rich growth conditions can increase the defect formation energy and may lower the defect density. Our post-growth annealing and crystal growth experiments proved that the Ga2S3-rich conditions did improve the optical quality of the Dy3+:PbGa2S4 crystal. The structure and composition of PGS were analyzed by XRD and EDS. The XRC result showed the crystal has a high crystalline quality. The changes of bond length were studied through XPS characterization and DFT calculations. The VGa and PbGa defects result in different XPS peaks of PbGa2S4 crystals fabricated under PbS-rich and Ga2S3-rich growth conditions. [ABSTRACT FROM AUTHOR]

This paper deals with a single-machine scheduling problem with a time-dependent learning effect. The goal is to determine the job sequence that minimise the number of tardy jobs. Two dominance properties, two heuristic algorithms and a lower bound to speed up the search process of the branch-and-bound algorithm are proposed. Computational experiments show that the branch-and-bound algorithm can solve instances up to 18 jobs in a reasonable amount of time, and the proposed heuristic algorithm MFLA performs effectively and efficiently [ABSTRACT FROM PUBLISHER]

We employ polarization-resolved femtosecond optical pump–probe spectroscopy to investigate the nonequilibrium photocarrier dynamics in excitonic insulator Ta2NiSe5. The electronic dynamics, including hot carrier cooling, exciton formation, and recombination in the timescale ranging from subpicoseconds to a few tens of picoseconds, have been established from the transient reflectivity spectra, showing strong in-plane anisotropy with respect to the probe polarization. Such anisotropic photocarrier dynamics possibly arise from the crystalline orientation dependence of the excitonic polarizability. Furthermore, we find that the amplitude of coherent phonons with a frequency of 1 THz is subject to the probe polarization, whereas it is not sensitive to the pump polarization. This substantiates that the displacive excitation of coherent phonons plays a decisive role in lattice dynamics. In addition, we find that the photo-induced dielectric screening tends to suppress the amplitude of coherent phonons with increasing pump fluence, manifesting a remarkable polarization dependence. Our work provides valuable insights into the excitonic dynamics and the origin of coherent phonon generation and also may contribute to the development of polarization-sensitive photoelectric devices based on Ta2NiSe5. [ABSTRACT FROM AUTHOR]