An electrospray/ultraviolet lamp dual-source ion trap mass spectrometer was developed for the rapid detection of gas and liquid samples.The instrument used the discontinuous atmospheric pressure sampling technique that both the electrospray ions and gaseous analytes were sampled and transferred using a pinch valve device.The two ionization sources were generally suitable for different kinds of analytes and provided complementary applications.Electrospray was used for the ionization of polar compounds in solution, while the UV ionization source was mainly applied for the analysis of gaseous organic compounds.A variety of samples such as anisole, toluene, 2,4-dimethylaniline, arginine, reserpine and aspartame were employed to test the performance in different working mode of the instrument.The results showed that the two sources were feasible for ionization of different types of samples, and different types of molecular ions could be generated when 2,4-dimethylaniline was analyzed.The two ionization sources could be used alternately or simultaneously without interference, and the working mode was also switched to fit the application requirements.The dual-source configuration was an effective way to extend the applications for miniature mass spectrometers.It did not significantly increase the size of the instrument, but provided more versatile analysis to meet the need for the measurement of different types of samples.

Objective To systematically review the effect of functional exercise on the prevention of radiation-induced trismus among patients with nasopharyngeal carcinoma(NPC). Methods Articles about the randomized controlled trials(RCT)of functional exercise to prevent radiation-induced trismus in patients with NPC after radiotherapy were retrieved from the established date of databases to the 31st December of 2018 in electronic databases such as Cochrane Library,PubMed,EMbase,China National Knowledge Internet (CNKI),VIP and Wanfang database. After literature selection,extraction and literature quality evaluation by two people according to inclusion and exclusion criteria,Revman 5.3 was used for Meta-analysis of outcome indicators. Results A total of 10 articles were enrolled,including 978 patients. The quality grade of all included literature was B. Maximum interincisal opening(MIO)is the outcome index of 6 articles. Meta-analysis showed that functional exercise could alleviate the reduction of MIO in NPC patients receiving radiotherapy [MD=4.59,95％CI(3.29,5.90),P<0.0001]. The degree of difficulty in opening the mouth was the outcome index of 8 articles. The results of Meta-analysis showed that functional exercise had a positive effect on the improvement of the difficulty of opening mouth in NPC patients[OR=0.23,95％CI(0.13,0.41),P<0.0001]. Conclusions Functional exercise can delay the process of reducing MIO of patients with NPC after radiotherapy,reducing the difficulty of opening the mouth,and have a positive effect on improving function and patients' quality of life.