We demonstrate a chip-based octave-spanning soliton microcomb in a whispering gallery mode microresonator platform. By fabricating a silica microdisk resonator and optimizing its dispersion with dry etching, we achieve an octave-spanning single-soliton microcomb with a repetition rate of ∼670 GHz at an optical pump power of 162.6 mW. Also, two dispersive waves at the end of the spectrum are observed to extend the comb spectral range and improve the comb power.

In water-to-air visible light communication (W2A-VLC), the dynamics of underwater nodes and a wavy water surface should not be neglected. This paper investigates the link performance by combining the dynamic effects of an underwater light-emitting diode (LED) transmitter with a wavy water surface. Monte Carlo simulation is first adopted to evaluate the underwater LED dynamics. Experimental tests are then conducted to measure and analyze the influence of underwater dynamic parameters on link performance, which shows results consistent with theoretical prediction. It is demonstrated that the swing angle dominates the stability and reliability of the W2A-VLC link under a dynamic water surface, providing some insight into the design of underwater optical transmitters.

Objective: To identify the obstacles preventing and controlling hepatitis B and put forward suggestions for its prevention and treatment by describing the discovery process of hepatitis B patients. Methods: We conducted face-to-face interviews with 50 hepatitis B patients in Chongqing, China from July to August 2019 by constructing a thematic analysis framework, which included interviewees’ social demographic characteristics, diagnosis approach, signs and symptoms at the time of discovery, feelings after diagnosis, and doctor’s instructions.Results: Most of the patients were firstly found hepatitis B via physical examination when patients were asymptomatic or had no obvious symptoms. The majority of them were shocked, frightened, and at a loss when they were diagnosed. The patients could remember doctor’s instructions on keeping healthy lifestyle, but they had very little impression about doctors’ reminding about regular liver function test. Failure of regular follow-up to liver function test brought irreversible loss for certain patients.Conclusions: Most of the patients were found hepatitis B passively. The patients need professional mental help after the diagnosis to overcome the negative emotion. The doctors’ instruction should emphasize more on the importance of regular follow-up to liver function test besides health lifestyle.