Objective To establish a gas chromatography-mass spectrometry (GC-MS) method for the simultaneous determination of four carbonate compounds (CCs), including ethyl methyl carbonate (EMC), diethyl carbonate (DEC), vinylene carbonate (VC), and ethylene carbonate (EC) in workplace air. Methods Vapor-phase EMC, DEC, VC, and EC in workplace air were collected using activated carbon tubes. After desorption with dichloromethane, the samples were analyzed by GC-MS. Qualitative identification was performed based on retention times and characteristic ions, while quantitative analysis was conducted using peak areas of selected characteristic ions. Results The quantitative determination ranges for the four CCs were from 0.57×10⁻³ to 200.00 mg/L, with correlation coefficients ≥0.999 45. The detection limit ranged from 0.17 to 1.60 μg/L, and the lower limit of quantification ranged from 0.57 to 5.33 μg/L. The minimum detection concentration and minimum quantitation concentration were 0.11-1.07 and 0.38-3.55 μg/m³, respectively. Mean spiked recoveries ranged from 85.70% to 111.65%. The intra- and inter-batch relative standard deviations were 0.11%-2.04% and 1.27%-5.18%, respectively. Mean desorption efficiencies of the method ranged from 74.70% to 118.20%. EMC, DEC, and EC samples were stable for up to five days at 4 °C, while VC samples were stable for up to three days at 4 °C. Conclusion The GC-MS method is suitable for the simultaneous determination of the four CCs including EMC, DEC, VC, and EC in workplace air.

This article reported a prenatally diagnosed case of complete ring chromosome 15. A 38-year-old woman who conceived by in vitro fertilization and frozen embryo transfer underwent amniocentesis for prenatal diagnosis at 18 +5 weeks of gestation due to advanced maternal age. The result of G-banding karyotyping was mos 46,XX,r(15)[88]/45,X,-15[11]/46,XX,r(15;15)[1]. No numerical abnormalities of chromosomes or definite pathogenic copy number variations (CNVs) were detected by chromosomal microarray analysis. Amniocentesis was performed again at 31 +6 weeks of gestation. The result of genome copy number variation sequencing indicated no pathogenic CNV and fluorescence in situ hybridization on cultured amniocytes revealed nuc ish(15q)×1[15]/(15q)×3[5]/(15q)×2[80]. Based on all the prenatal diagnosis results, it was suggested that the fetus carried a complete ring chromosome 15. As the peripheral blood chromosomes of the couple were normal and no obvious abnormalities were detected by the prenatal ultrasound either in our hospital or another hospital, the pregnant woman decided to continue the pregnancy after genetic counseling and delivered a baby girl at 41 weeks of gestation. The girl showed no physical abnormalities during a seven-month follow-up.

Objective:To explore the effect of standardized training and intelligent assessment system for nurses.Methods:In August 2020 and August 2021, convenience sampling was used to select new nurses who received standardized training at Beijing Tiantan Hospital affiliated with Capital Medical University as participants. Forty-two new nurses in August 2020 were designated as control group, and 42 new nurses in August 2021 were designated as intervention group and assessed through an intelligent assessment system. The assessment costs of two groups of nurses were compared.Results:Intervention group had shorter pre-exam preparation time, pre-exam waiting time, score summary time, and consumables costs compared to control group, and the differences were statistically significant ( P<0.05) . Conclusions:The construction of an intelligent assessment system improves the scientificity, effectiveness, and fairness of standardized training for nurses. Continuous improvement and perfection are still needed in the future.

This study aimed to identify the related substances of lorazepam tablets by liquid chromatography mass spectrometry (LC-MS). To separate the related substances of lorazepam tablets, gradient elution was performed using acetonitrile and 0.1% acetic acid -20 mmol/L of ammonium acetate as mobile phase on Inert Sustain C18 (250 mm × 4.6 mm, 5 μm).The accurate mass and elemental composition of the parent ions and their product ions of related substances were determined by electrospray-ionization quadrupole time-of-flight high resolution mass spectrometry (ESI-Q-TOF/MS).The structures of the related substances were identified by spectral analysis. Under the established analytical condition, lorazepam and its related substances were adequately separated, and 22 major related substances with content greater than 0.1% were detected and identified by hyphenated techniques in lorazepam tablets and their stressed samples.Among them, 5 were the impurities listed in the USP or EP, and the others were unknown related substances identified for the first time in this paper.The LC-MS technique can effectively separate and identify the related substances of lorazepam tablets, which provides some reference for quality control.

Objective To explore the current situation of stressor,job burnout and anxiety of pediatric nurses of Class Ⅲ Grade A hospitals and to analyze the correlation between stressor and job burnout as well as stressor and anxiety.Methods From January to February 2017,a total of 233 pediatric nurses of 5 Class Ⅲ Grade A hospitals of Beijing were selected by convenience sampling as subjects.All of the pediatric nurses were investigated with the Nurse Job Stressor Scale (NJSS),Maslach Burnout Inventory-Human Services Survey (MBI-HSS),Self-Rating Anxiety Scale (SAS).Results Among 233 pediatric nurses,two dimensions of NJSS with high scores included time allocation and workload (2.69 ± 0.87) as well as patient care(2.54 ± 0.70).Two items of NJSS with high scores contained that the wages and other welfare treatment was low (3.04 ± 0.93) as well as worrying about mistakes and accidents in work (2.97 ± 0.97).The emotion exhaustion dimension of MBI-HSS was with 22.7％ for the severe level.Patients with low scores of sense of personal achievement accounted for 41.2％.The score of SAS was (38.38 ± 7.47) significantly higher than Chinese model (t=17.57,P ＜ 0.01).There were 10.7％ of nurses with the moderate-severe level of anxiety.The correlation analysis among stressor,job burnout and anxiety of pediatric nurses showed that except for time allocation and workload as well as sense of personal achievement,other dimensions of NJSS had positive correlations with dimensions of MBI-HSS and SAS (r=0.169-0.527,P ＜ 0.05).Conclusions Pediatric nurses are with high working pressure.Policy makers and managers should consider characteristics in pediatric nursing,reduce nurses' stressors as well as the level of nurses' job burnout and improve their mental health,so as to ensure the quality of pediatric nursing.