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Objective: This study aimed to eslablish a method for the determination of 15 benzodiazepine sedatives in aquatic products by liquid chromatography tandem mass spectrometry （HPLC-MS/MS）. Methods: The sample was extracted with acetonitrile solvent, and the extract was purified by solid phase extraction （Oasis PRIME HLB） column. After concentration, the mobile phase was used to determine the volume. The mobile phase consisted of 1% formic acid aqueous solution and acetonitrile solvent. The method was performed in multiple reaction monitoring （MRM） mode and quantified by internal standard method. Results: The results showed that the linear range of 15 sedatives was 1~100 ng/mL （R＞0.99）. The limit of detection （LOD） was 0.1~0.3 μg/kg and the limit of quantification （LOQ） was 0.3~1.0 μg/kg. The average recoveries were 78%~125% and the relative standard deviations （RSD） were 1.52%~12.02%. Conclusion: The method has the advantages of simple pretreatment, good purification effect and accurate results. It is suitable for the rapid detection of 15 kinds of sedatives in aquatic products.

Thiopurine dose optimization by thiopurine-S-methyltransferase (TPMT) or nudix hydrolase-15 (NUDT15) significantly reduced early leucopenia in Asia. However, it fails to avoid the late incidence (> 2 months). Although laboratory monitoring of 6-thioguanine nucleotides (6TGN) to optimize thiopurine dose was suggested in White patients the exact association between leucopenia and 6TGN was controversial in Asian patients. In the present study, we aimed to explore whether DNA-thioguanine nucleotides (DNA-TGs) in leukocytes, compared with 6TGN in erythrocytes, can be a better biomarker for late leucopenia. This was a prospective, observational study. Patients with inflammatory bowel disease (IBD) prescribed thiopurine from February 2019 to December 2019 were recruited. Thiopurine dose was optimized by NUDT15 C415T (rs116855232). DNA-TG and 6TGN levels were determined at the time of late leucopenia or 2 months after the stable dose was obtained. A total of 308 patients were included. Thiopurine induced late leucopenia (white blood cells

Background This study was designed to assess stress levels and related factors during the coronavirus disease 2019 (COVID-19) epidemic among individuals in centralized quarantine camps in Wenzhou, China. Methods The survey was conducted using a questionnaire. The questionnaire included questions on sociodemographic characteristics, life events related to the COVID-19 and stressful situations, as well as Perceived Stress Scale-14. Participants included close contacts of patients with COVID-19 or at-risk individuals in quarantine camps. Multivariate logistic regression was used to analyze different factors affecting perceived stress. Results The prevalence of high stress among quarantine camp participants was 37.45%. Of the 881 respondents, 51.99% were concerned about the difficulty of controlling the epidemic, 46.20% were concerned about the health of themselves and their family members and 39.61% were concerned about not being able to leave their homes. Multivariate logistic regression analysis revealed statistically significant differences in the prevalence of stress among different groups for certain variables, including occupation, education level and knowledge of COVID-19 (all P  < 0.05). Our study found that at-risk individuals and close contacts experienced high levels of stress in quarantine camps during the COVID-19 pandemic. Conclusions These findings suggest that centralized quarantine policies should be adapted and optimized to minimize negative psychological effects on quarantined individuals. [ABSTRACT FROM AUTHOR]

A novel horn antenna based on a circular groove guide was analyzed and measured at Ku-band and Ka-band, respectively. This horn antenna can cover a frequency range from 14 to 40 GHz. Its optimum dimension was obtained according to the maximum directivity. The antenna can be matched efficiently to free space through its large aperture. Moreover, its input VSWR is low. The theoretical radiation patterns are close to the measured ones. Index Terms--Antenna, circular groove guide, groove guide, horn antenna, wide-band antenna.