Manipulation of the high-order harmonic generation in monolayer hexagonal boron nitride by two-color laser field.

We theoretically investigate the high-order harmonic generation (HHG) of the monolayer hexagonal boron nitride by two-color laser pulses, based on the ab initio time-dependent density-functional theory. We find that the waveform of the two-color laser field can dramatically control the harmonic spectrum. The two-color laser field can enhance the harmonic radiation more efficiently than the monochromatic pulse laser with the same incident energy. We investigate the influence of incident laser pulse parameters on the harmonic radiation, such as the relative phase of the two-color field, the amplitude ratio between component electric fields, and the laser orientation. We show that the HHG spectrum is controlled by both the electric field and the vector potential. The electronic band structure and the laser-matter energy transfer play an important role in determining the laser polarization for optimal HHG in the hBN crystal. Our work supplies a scheme to manipulate HHGs in two-dimensional materials and provides a potential methodology for the generation of intense extreme-ultraviolet pulses.

[Clinical effect of a scrotal rapid recovery dressing device in the treatment of acute epididymitis].

OBJECTIVE: To study the protective effect of a scrotal rapid recovery dressing device, scrotal girdle, on the scrotum of the patient with acute epididymitis, so as to improve the prognosis and the patient's satisfaction. METHODS: A total of 120 patients with acute epididymitis were treated in our hospital from December 2018 to November 2019, 60 with the scrotal girdle plus local cold compress in addition to antibiotics administration (the scrotal girdle group) and the other 60 with antibiotics only (the control group), all for 6 days. Then, comparisons were made between the two groups of patients in the improvement of scrotal swelling, total effectiveness rate and the patients' satisfaction with therapeutic outcomes. RESULTS: After 6 days of treatment, the patients in the scrotal girdle group, compared with the controls, showed significantly lower scrotal swelling scores (1.01 ± 0.34 vs 1.38 ± 0.20, P < 0.05), a higher total effectiveness rate (83.33% vs 65%, P < 0.05) and higher satisfaction with the therapeutic outcomes (86.67% vs 56.67%, P < 0.05). CONCLUSIONS: For the treatment of acute epididymitis, the application of the scrotal girdle for protection can significantly relieve scrotal pain and discomfort, improve the therapeutic effect and patients' satisfaction, and enhance the patients' recovery and quality of life.

[Application value of a metamorphic mechanism-based special dressing system for patients after scrotal surgery].

OBJECTIVE: To investigate the application of a metamorphic mechanism-based special dressing system (MMDS) in improving the prognosis and comfort of the patient after scrotal surgery. METHODS: We included 48 cases of scrotal surgery using the traditional method for postoperative dressing from June 2017 to June 2018 (the control group) and another 48 cases employing MMDS postoperatively from July 2018 to June 2019 (the MMDS group). We observed the differences between the two groups of patients in the incidence of scrotal edema, pain score, hospitalization days, patients' satisfaction, and dressing time. RESULTS: The scrotal edema score showed no statistically significant difference between the MMDS and control groups at 24 hours after operation (P > 0.05) but remarkably lower in the former than in the latter group at 48 hours (1.42 ± 0.5 vs 2.27 ± 0.7, P < 0.05) and 72 hours postoperatively (1.35 ± 0.2 vs 2.25 ± 0.7, P < 0.05). The MMDS group, compared with the controls, also exhibited a lower pain score (2.2 ± 1.0 vs 3.4 ± 1.5, P < 0.05), shorter hospitalization time (ï¼»5.96 ± 1.2ï¼½ vs ï¼»9.13 ± 2.3ï¼½ d, P < 0.05) and higher satisfaction score (98.1 ± 1.6 vs 92.8 ± 2.8, P < 0.05), as well as shorter dressing time at 24, 48 and 72 hours after operation (P < 0.05). CONCLUSIONS: The metamorphic mechanism-based special dressing system is a safe, efficient, simple and feasible method for dressing after scrotal surgery, which can effectively promote recovery and improve the quality of life of the patients.