OBJECTIVEThe main purpose of this work was to give the evidence of reasonable and feasible dust control measures which will be taken in the future by analyzing the trend of dust concentration from 1991 to 2010 and identifying working faces with the severe dust contamination in one underground iron mine.

METHODSThe data was from routine monitoring between the years 1991 and 2010, which enclosed the total dust concentrations and silica contents. China National Standard of Occupational exposure limits for hazardous agents in the workplace used to judge whether the dust concentration exceeded the National Standard.

RESULTSThe general trend of total dust concentration from 1991 to 2010 was decreased, especially maximum and average levels. The highest exceeding rate was 43.16% in 1993 and the best years were 2009 and 2010, but the exceeding rates were still over 30%. The dust exposure levels varied with different work faces. The mining and supporting were the most severe dust pollution faces which the highest ultra exceeding rates were 51.61% and 51.48% and the maximum exceeding times were 64.6 and 16.4 respectively. The next was constructing face with 40.23% exceeding rate and 24.6 times more than standard.

CONCLUSIONThe trend of total dust concentration from 1991 to 2010 was decreased, but the dust exceeding rate was still high. The strong measures should be taken to control the dust pollution in this iron mine, especially mining and supporting faces.

Air Pollutants, Occupational ; analysis ; Dust ; analysis ; Environmental Monitoring ; Iron ; analysis ; Mining ; Occupational Exposure ; analysis

Objective To investigate certified specialized nurses' willingness in building an reappraisal system and to provide a basis for further completing the appraisal system and criteria for specialized nurses, defining their roles, and encouraging them to play their leading roles in clinical work.Methods Totally 250 certified specialized nurses from 8 Class Ⅲ hospitals in Beijing were selected by convenient sampling and investigated with the self-designed questionnaire. The subjects' willingness in building the reappraisal system and criteria were analyzed.Results In terms of the 240 specialized nurses' wiliness in building the reappraisal system, their scores in clinical competence, teaching ability and research capability were (13.14±3.86), (13.60±2.27) and (9.50±2.94), respectively. There was statistical difference in the willingness in building the evaluation criteria of clinical competence between specialized nurses with different length of service and titles (P<0.05); there was also statistical difference in the willingness in building the evaluation criteria of teaching ability between specialized nurses with different educational background (P<0.05).Conclusions The specialized nurses' willingness in building the reappraisal indicators. Nursing managers shall train specialized nurses based on their shortcomings, build stricter criteria for future training for specialized nurses, and encourage the nursing team to become expert nurses.

OBJECTIVE To explore the the reg ulation of intestinal flora and effects of Qingjie huagong decoction on intestinal mucosal barrier in severe acute pancreatitis （SAP）mode rats . METHODS SAP rat model was induced by intraperitoneal injection of caerulein and lipopolysaccharide.The survival state of rats in each group were observed.The levels of serum amylase ，interleukin 10（IL-10），IL-18 and IL- 1β in serum were all detected. The pathological changes of pancreatic and small intestinal tissue were observed. The expressions of Occludin，ZO-1 and HMGB1 were detected in small intestinal tissue of rats. The structure and relative abundance of intestinal microflora in rats were detected by 16S rRNA high throughput sequencing. RESULTS After the intervention of Qingjie huagong decoction ，abdominal distension symptoms of SAP model rats were significantly relieved ，and their mental state recovered better ；the levels of serum amylase and IL- 18 in serum were decreased significantly （P＜0.05），while the level of IL- 10 was increased significantly （P＜0.05）. The necrotic area of pancreatic tissue and the infiltration of inflammatory cells were reduced ， the degree of intestinal epithelial cell structural disorder was alleviated ，and the shedding of intestinal mucosal epithelium was reduced.The protein expression of HMGB 1 in small intestinal tissue was decreased significantly （P＜0.05），and the protein expression of Occludin and ZO- 1 were increased significantly . Results of 16S rRNA high throughput sequencing showed that Qingjie huagong decoction could increased the relative abundance of probiotics such as Bacteroidea and Lactobacillus in rat intestine ，reduced the colonization of harmful bacteria such as Firmicutes. CONCLUSIONS Qingjie huagong decoction can improve the intestinal barrier by up-regulating the expression of Occludin and ZO- 1 in small intestinal tissue and down-regulating the protein expression of HMGB 1. It can also adjust the relative abundances of different flora to protect the intestinal tract.