Yi F.,Shandong Jiaotong University |
He R.,Jiangsu University |
Luo Z.,Wuhan University of Technology |
Luo Z.,Hubei Institute for Food and Drug Control
Chemical Engineering Transactions | Year: 2015
Permanent magnet retarder wins high favor of large cars with easy installation, low power consumption and small size. But this retarder is easily affected by outside conditions or road conditions, so that the temperature field, the magnetic field, the relationship between design parameters will be changed, and the brake torque will further be affected. Through research we found that the parameter design of permanent magnet retarder is the most important point. An optimized parameter enables the brake torque to come into full play and to adjust its external environment. The paper presents the parameter optimization design model of permanent magnet type retarder based on neural network algorithm. In the model, the design parameters of permanent magnet retarder is taken as input values, all influencing factors as the hidden layer of neural network, and the weight coefficient and threshold values of various scene parameters are constantly adjusted to conform to meet practical needs. In addition, according to the results of the output layer, the values of the design parameters are constantly adjusted to reach the ultimate goal of optimizing the design parameters. The comparison of experimental analysis shows that with practicability and reliability, the model can provide a more intelligent, simpler method for the design of permanent magnet retarder. Copyright © 2015, AIDIC Servizi S.r.l.
Kang S.,Hubei Institute for Food and Drug Control
Zhongguo Zhongyao Zazhi | Year: 2011
Objective: To develop a HPLC method for the determination of synephrine and arecoline contents in Xiao'er Xiaoji Zhike oral liquid. Method: The analysis was performed on a Symmetry C18 column (4. 6 mm x 250 mm, 5 μm) eluted with acetonitrile-methanol-0. 1% acetic acid solution (containing potassium dihydrogen phosphate 0. 6 g and SDS 1. 0 g per 1 000 mL) (15: 30: 55)as mobile phase. The detection wavelength was set at 215 nm. Result: The synephrine and arecoline concentrations had good linear relationship between 0. 281 5-2. 815 and 0. 040 16-0. 401 6 μg (r>0. 999 7), and the average recoveries of the two compounds were 97. 1% (RSD 1. 4%) and 100% (RSD 1. 3%), respectively. Conclusion: The method is simple, accurate and sensitive.
Jin J.-L.,Hebi Polytechnic |
Zhu R.-S.,Hebi Polytechnic |
Xie Y.-Y.,Hubei Institute for Food and Drug Control |
Liu H.-C.,Zhengzhou University
Chinese Journal of Cancer Prevention and Treatment | Year: 2016
OBJECTIVE: To explore the new method of treating melanoma and investigate the effect of CDK2 gene silence mediated by lentivirus on the growth of melanoma cell line B16-F1 in the C57BL/6 mice. METHODS: B16-F1 cells were injected into the right groin of C57BL/6 mice to establish the transplanted tumor model, which were randomly divided into three groups according to the material injected into the cancer foci: blank control group, negative control group and experimental group,5 mice in each group, each group was treated for 6 times, the growth status of the tumor was observed, tumor volume was measured, tumor growth curve was drawn, tumor weight was weighed after 18 days treatment and the tumor growth inhibition rate was calculated. Apoptosis of tumor cells was inspected by TUNEL. Expression of CDK2 protein in tumor tissues was detected by Western blot. RESULTS: Three days after inoculation of tumor cells, the tumor formation in C57BL/6 mice was observed. The mean volume of the blank control group, negative control group and experimental group were (48.7±8.4) mm3, (50.0±8.9) mm3 and (31.4±8.7) mm3 at the sixth day of treatment respectively. Compared with the blank control group and the negative control group, the growth rate of tumor in the experimental group was significantly decreased from the sixth day of treatment(F=8.879,P=0.004). The tumor weight of the three groups at the end of experiment was (0.56±0.10) g,(0.55±0.11) g and (0.28±0.07) g respectively. Compared with the two control groups, the tumor weight of the experimental group was significantly decreased (F=13.659,P=0.001), the tumor growth inhibition rate was 50.2% compared with that of the blank control group. The apoptosis index of tumor cells in the above three groups was (7.73±1.08)%,(7.87±1.42)% and (32.27±3.62)% respectively. Compared with the two control groups, the apoptosis index of tumor cells in experimental group was significantly increased (F=189.748,P<0.001). The expression of CDK2 protein in experimental group was significantly decreased compared with the two control groups(F=293.346,P<0.001). The inhibition rate of CDK2 protein expression in the experimental group was 50.4% compared with the blank control group. CONCLUSIONS: The growth of B16-F1 cell transplanted tumor can be effectively inhibited by CDK2 gene silencing. It suggests that CDK2 gene may be an effective target for gene therapy of melanoma in future. © 2016, Editorial Board of Chinese Journal of Cancer Prevention and Treatment. All right reserved.
Approach to lattice-related/content-specific spectral ranges of near-infrared diffuse reflectance spectroscopy of cefazolin sodium and the construction of a quantitative model for the determination of cefazolin sodium content in different crystal forms
Liu Y.,National Institutes for Food and Drug Control |
Liu Y.,Hubei Institute for Food and Drug Control |
Feng Y.,National Institutes for Food and Drug Control |
Jia Y.,National Institutes for Food and Drug Control |
And 2 more authors.
Science China Chemistry | Year: 2013
Cefazolin sodium can form both α- and β-form crystals. It also can form dehydrated crystalline and amorphous products through different production processes. Because different polymorphic medicines usually have different physical and chemical properties, it is critical to emphasize the crystallization control of polymorphic medicines. Near-infrared (NIR) analysis, which incorporates a combination of NIR spectroscopic techniques and multivariate chemometric methods, is considered a powerful tool for the determination of the crystallinity of polymorphic drugs. The selection of optimal spectral ranges that correlate with the lattice specificity and content specificity is crucial to obtaining a specific NIR model. In the present work, near-infrared (NIR) spectra of cefazolin sodium with different crystal forms created through different processes were studied. The results suggest that wavelengths within the range of 9102.7-8597.5 cm-1 is related to the specificity of the cefazolin sodium crystal lattice and that the range of 6001.6-5496.4 cm-1 is associated with the quantitative content of cefazolin sodium. The two absorptions are caused by the second overtone of the C-H stretching band (3υC-H) and the first overtone of C-H stretching band (2υC-H), respectively. Using these results, we established a suitable method of constructing a universal quantitative model by using mixed samples in different crystal forms as a calibration set, selecting a content-specific range (6001.6-5496.4 cm-1), and adding lattice-related spectral ranges where appropriate. This may provide a framework for the construction of prediction models for polymorphic medicines. © 2013 Science China Press and Springer-Verlag Berlin Heidelberg.
Xu Y.L.,Hubei University of Chinese Medicine |
Nie J.,Hubei Institute for Food and Drug Control
Zhong yao cai = Zhongyaocai = Journal of Chinese medicinal materials | Year: 2013
To explore the phylogenetic relationships among medicinal leeches and their closely related species by comparing their ITS gene fragments. 8 different leech species, including Whitmania pigra, Whitmania acranulata, Whitmania laevis, Hirudo nipponia, Poecilobdella manillensis, Poecilobdella javanica, Poecilobdella hubeiensis and Erpobdella octoculata were collected as the materials for study. After the total DNA of all samples was extracted, amplified by PCR and cloned, their ITS sequence, AT content, variable sites and evolutionary relationships were analyzed. The length of ITS was 948-981 bp with 210 variable sites and 43 inserts on/deletion. The average G + C content was high up to 56.0%-57.8%. The aligned ITS sequence demonstrated that their ITS genes were relatively conserved in species. Data analysis showed that the relationship between E. octoculata and P. javanica was closer than others, their genetic distance was only 0.007. Through the phylogenetic tree analysis, three species of Haemopidae and four species of Hirudinidae were obviously clustered into two branches. The results support the taxonomic status of Haemopidae and Hirudinidae, and provide sufficient evidences that Erpobdella octoculata and Poecilobdella javanica should not be assigned to two genera, of which the taxonomic system should be further researched.