Objective To investigate the accuracy of three dimensional facial measurement system based on structured light projection, and explore the methods to reduce noise of the output images. Methods The known object for calibration was measured by the measurement system to correct the parameters of the system and enhance the measurement accuracy. The mechanism of noise was analysed, and the noise and sundry of the images were eliminated. Results The parameters of each assembly of system were obtained by calculation and calibrated, and the measurement accuracy (0.028 mm) of three dimensional facial measurement system based on structured light projection was increased. Application of image processing technology reduced the noise and sundry of output images. Conclusion The accuracy of three dimensional facial measurement system based on structured light projection is high. The image output is reliable, and can be clinically used in facial scanning and three dimensional reconstruction.

OBJECTIVETo investigate the permance index ofof portable X-ray fluorescence spectrometer in the determination of lead on filter membrane and to provide data for the determination of lead in workplace air.

METHODSIrradiated with X-ray, the lead would emit specific X-ray fluorescence during the process from the excited state back to the ground state. Rapid determination of lead was completed using fluorescence energy and wave length for qualitative analysis and fluorescence intensity for quantitative measurement. Under set conditions, a series of customized calibration samples were measured to create a standard curve for quantitative analysis of lead on filter membrane.

RESULTSThe regression equation obtained using a portable X-ray fluorescence spectrometer to determine the lead on filter membrane was y=0.004x-0.182 (r2= 0.9999). The linear range was 0.00 -10.40 mg/m3, the minimum detectable concentration was 0.53 µg/m3, and the minimum quantifiable concentration was 1.76µg/m3. The relative standard deviation (RSD) of within-run precision of samples with different concentrations was 0.48%-6.22%, the RSD of between-run precision was 2.51%-5.09%, and the degree of accuracy was in the calibration range of standard samples.

CONCLUSIONPortable X-ray fluorescence spectrometry is a simple, rapid, repeatable, and accurate method for the determination of lead on filter membrane.

Air Pollutants, Occupational ; analysis ; Lead ; analysis ; Spectrometry, X-Ray Emission ; Workplace

Objective To evaluate the effects of KIM-1 on high glucose induced the expression of MCP-1 and FN in rat tubular epithelial cells and to explore the possible mechanisms of KIM-1 involved in renal interstitial fibrosis of DN.Methods The rat renal tubular epithelial cells (NRK52E) were cultured in vitro and divided into five groups:Normal control group (D-glucose 5.6 mmol/L),Hypertonic group (D-glucose 5.6 mmol/L + D-mannitol 24.4 mmol/L),High glucose group (Dglucose 30 rmmol/L),Control siRNA group,KIM-1 siRNA group.ELISA assay was used to assess the levels of MCP-1 and FN in the cells supernatant; Western blotting was used to detect the protein expression of KIM-1; RT-PCR was used to detect mRNA expression of KIM-1,MCP-1 and FN.Results Compared with the control group,the protein and mRNA expression of KIM-1 in the high glucose group were increased at 12 h (P ＜ 0.05),and reached the peak at 48 h (P ＜ 0.05); the protein and mRNA expression of MCP-1 and FN in high glucose group were increased at 24 h significantly (P ＜ 0.05),and peaked at 48 h (P ＜ 0.05).Compared with the high glucose group,the protein and mRNA expressions of MCP-1 and FN in KIM-1 siRNA group were decreased (P＜0.05).Conclusions Down-regulating the expression of KIM-1 can significantly inhibit the expression of MCP-1 and FN,which suggests that KIM-1 may be involved in renal interstitial fibrosis of DN by regulating expression of MCP-1 and FN.

To improve the yield of sucrose isomerase from Pantoea dispersa UQ68J, we studied the effect of different signal peptides and fermentation conditions on sucrose isomerase expression in Escherichia coli. The gene of sucrose isomerase was optimized and expressed in E. coli BL21 (DE3) with native signal peptide which was named as ORI strain. The total and extracellular enzyme activity was 85 and 65 U/mL in the flask, respectively. The mature protein, which started from the 22th amino acid, was connected with the PelB and OmpA signal peptide to construct P22 and O22 strain, respectively. The total activity of P22 reached 138 U/mL, which was 1.6 times of ORI strain. The total activity of O22 strain was similar to that of ORI strain. Induced by 3.0 g/L lactose, the total activity of P22 strain increased to 168 U/mL. In 3 L fermentor, the effects of glycine concentration and induction time were studied. Induction when the DCW reached 18 g/L (OD₆₀₀=30), with 0.5% glycine, the extracellular enzyme activity reached 1 981 U/mL, and the total enzyme activity reached 2 640 U/mL, which is the highest activity of sucrose isomerase that was expressed in recombinant E. coli.
Bacterial Proteins ; biosynthesis ; Bioreactors ; Escherichia coli ; metabolism ; Fermentation ; Gene Expression ; Glucosyltransferases ; biosynthesis ; Lactose ; Pantoea ; enzymology ; Protein Sorting Signals ; Recombinant Proteins ; biosynthesis