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Cutting gearbox with complex structure is difficult to obtain mechanical parameters and conduct fault diagnosis, aiming at this problem, a novel handling method is proposed after studying vibration theory of gearbox. Firstly, traditional calculation method and modal analysis are combined to acquire mechanical parameters of gearbox, especially inherent frequencies of decelerator housing and gear transmissions which are difficult to calculate. Based on Haar-Wavelet, vibration test signal of cutting gearbox is de-noised. And Fast Fourier Transform (FFT) is conducted for de-noised signal, thus operation status of gearbox can be analyzed in time domain and frequency domain. Taking a mine cutting gearbox as an example, the method proposed is used to detect parts damage in maintenance process. It is found that the tooth surface of second-stage gear transmission arise even wear, and this is consistent with actual situation. Therefore the practicability and effectiveness of this method are verified, and a new solution is provided for other gearboxes with complex structure.

Prostate cancer is a kind of malignancy with high occurrence in the male urogenital system. However, the mechanism of the occurrence, the progression, and the metastasis of prostate cancer are still unclear. Searching for the effective molecule target is of great significance to improve the curative effect on prostate cancer. Zinc finger E box binding protein-1 (ZEB1) protein is a member of the zinc finger transcription factor family that participates in the embryonic development and formation. ZEB1 was found to be involved in the occurrence and in the development of multiple cancers, while its role in prostate cancer still needs elucidation.Normal prostate cell line PC-3M and prostate cancer cell line DU145 were cultured in vitro and transfected by ZEB1 siRNA. ZEB1 mRNA and protein expressions were detected by real-time PCR and Western blot assay. Cell proliferation was determined by using 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) assay. Cell migration was evaluated by transwell assay. Cell apoptosis was evaluated by caspase-3 activity. The impact of ZEB1 on extracellular signal-regulated kinase 1 and 2 (ERK1/2) signaling pathway was assessed by Western blot assay.ZEB1 expression significantly increased in DU145 cells compared with PC-3M cells (p0.05). ZEB1 mRNA and protein obviously declined, cell proliferation inhibited, cell invasion suppressed, and Caspase-3 activity enhanced in DU145 cells after ZEB1 siRNA transfection (p0.05). ZEB1 siRNA markedly decreased ERK1/2 phosphorylation in DU145 cells compared with control (p0.05).Inhibition of ZEB1 promoted prostate cancer apoptosis, restrained proliferation, and suppressed invasion through down-regulating ERK1/2 signaling pathway.

Invasive lobular carcinoma of the breast to breast cancer cells in the breakthrough of mammary gland flocculus endings tube or to lobular acini basement membrane mesenchymal invasive growth as the main characteristics.Breast invasive lobular carcinoma usually has a better prognosis of phenotype, low-level histological grade, low mitotic index, hormone receptor-positive,its her-2 negative, P53, low, lack of calcium mucin, sensitivity to endocrine therapy.Tended to be older patients diagnosis, tumor larger, axillary lymph node metastasis rate is higher, when a side breast invasive lobular carcinoma, the contralateral tend to occur.Invasive lobular carcinoma invasive is strong, has extensive transfer value tendency, therefore, in some studies in comparison with other invasive carcinoma with poor prognosis.

Cold is a typical environmental stress factor that limits the geographical distribution and growth of various plants. It affects crop quality and productivity. In the contemporary years, with the plant cold-resistant genetic engineering development, great progress was obtained in this field. This paper gave a general statement about the development of plant cold resistantance on the level of unsaturated fatty acids, protective enzymes, functional genes and regulation genes, aiming to provide some useful information and ideas to researchers who work on plant cold breeding and the mechanism of cold resistance. As research continues, we could develop further multiple resistant plant species.

Thermo-elastic-plastic (TEP) method is a method that can accurately predict welding deformation and residual stresses, but the premise is to select the appropriate heat source parameters. Aiming at the two welded joints in the stiffened plate studied in this paper, the welding experiments of simple components were carried out respectively, and the corresponding welding deformation and residual stresses were measured. Based on the welding experiment, the corresponding TEP model was established, and the corresponding heat source parameters were obtained according to the experimental data. The comparison between the experimental results and the numerical results shows that the obtained heat source parameters can well predict the welding deformation and residual stress of the welded structure. And then, the obtained heat source parameters were applied to the TEP model of the stiffened plate. The prediction results show that the T-type fillet welds of the stiffened plate can reduce the angular deformation caused by the butt welds to a certain extent. In addition, we can also find that the heat of the subsequent welds can reduce the residual stresses at the completed welds. This method not only can save a lot of experimental costs and time, but also can accurately predict the welding deformation and residual stresses.

To observe pharmacokinetic changes under simulated weightlessness in relevant to body flood flow changes.Gentamicin was selected as probe drug in the present study, and rabbits exposed to Head-Down Tilt (HDT, -20 degrees) immobilization were selected as simulated weightlessness animal model. Seven rabbits were treated inf. with 3 mg/kg of gentamicin sulfate pre-HDT and 7 d after HDT. Gentamicin blood samples within 4 h after administration were analyzed by TDxFLx.The distribution of gentamicin postponed significantly: a significant decrease in alpha from (0.1838 +/- 0.1076) min-1 before HDT to (0.0591 +/- 0.0334) min-1 after HDT; a significant increase in t1/2 alpha from (5.30 +/- 3.55) min to (15.04 +/- 7.49) min; a significant decrease in k12 from (0.1025 +/- 0.0721) min-1 to (0.0181 +/- 0.0161) min-1, a increase trend in V(C) and V(D). After HDT, CL(S) of gentamicin increased from (2.2 +/- 0.5) ml min-1 kg-1 to (2.7 +/- 0.3) ml min-1 kg-1.Simulated weightlessness might induce pharmacokinetic changes.

Olfactory epithelium (OE) is unique in the adult nervous system for it produces new neurons throughout life. The cultured cells of adult mouse OE in vitro were studied by histochemistry and immunocytochemistry techniques, and the results showed that they were neurons as up to 50% of the bipolar cells were immunopositive to NF, NSE, MAP2, OMP and tau. The effects of basic fibroblast growth factor (bFGF) and brain-derived neurotrophic factor (BDNF) in OE medium with different concentration serum on OE cell number and development of cell processes were also observed. The results showed that the combination of bFGF and BDNF added to 10% and 5% serum OE medium increased the bipolar cell number and percentage, stimulated the process outgrowth of bipolar cells, and decreased the numbers of giant cells and fusiform cells. The effects of the combination of bFGF and BDNF in the 10% serum OE medium were more significant than those of bFGF and BDNF applied alone; and the effects of neurotrophic factors in the 10% serum OE medium were more significant than those observed in the 5% serum OE medium.

Objective. To assess the effect of 7 d -6 degrees HDT on electromyogram of the weightbearing muscles. Method. Eight healthy males, aged 33-42, were exposed to -6 degrees HDT bed-rest for 7 d, electromyogram from the gastrocnemius and anterior tibialis muscles were recorded before and after HDT, and day 4 of recovery. Result. The latency of SLR (short latency response) recorded from lower leg muscles after HDT was not different from that pre-HDT. But the latency of MLR (middle latency response) and LLR (long latency response) after HDT were significantly increased as compared with that pre-HDT, and recovered to pre-HDT level on day 4 of recovery. The durations of SLR recorded from right leg muscles after HDT were significantly longer as compared with that pre-HDT, and did not recover. The integrated amplitude of SLR and MLR after HDT were significantly increased as compared with that pre-HDT, and only the integrated amplitude of SLR recovered, but that of MLR did not. Conclusion. Seven day -6 degrees HDT bed-rest had significant effects on electromyogram of the weightbearing muscles.

To quantitatively assess the effects of 7 d -6 degrees head-down bed-rest (HDBR) on postural equilibrium and to investigate the contributions of vestibular, somatosensory and visual informations to postural equilibrium.Eight healthy males, aged 33 - 42 years, were exposed to -6 degrees head-down tilt bed rest for 7 d. Sensory Organization Test (SOT) and Motor Coordination Test (MCT) were measured before and after HDBR, and day 4 of recovery.Equilibrium scores of SOT in condition 1 (eyes opened, platform and visual scence environment fixed), 5 (eyes closed visual scence environment fixed, platform movable) were significantly lower as compared with pre-HDBR value, and recovered to pre-HDBR level on day 4 of recovery. Postural strategy scores of SOT in condition 1, 2 (eyes closed, platform and visual scence environment fixed) and 3 (eyes opened, platform fixed, visual scence environment movable) were significantly lower as compared with pre-HDBR value, and recovered to pre-HDBR level on day 4 of recovery. The dependence of somatosensory and visual information (ratio pair codition 2/condition 1, condition 3/condition 1 in sensory analysis) was significantly higher as compared with pre-HDBR value, and recovered on day 4 of recovery. Mean SOT alignment scores in conditions 1, 4 (eyes opened, visual scence environment fixed, platform movable) and 6 (eyes opened, platform and visual scence environment movable) were significantly higher as compared with pre-HDBR value, and only the scores of conditions 1, 6 were recovered on day 4 of recovery, but that of condition 4 did not. Mean postural-evoked response latencies of MCT were not significantly different as compared with pre-HDBR value.7 d -6 degrees head-down tilt bed-rest has significant effects on postural equilibrium. The contributions of somatosensory and visual informations to postural equilibrium are increased.