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The development of the powder metallurgy (PM) superalloy applied in turbine discs of high thrust-weight ratio aeroengines was reviewed. Based on the Cosserat continuum theory, the elastoplastic damage model for the PM superalloy was developed in which the microscopic properties were modeled with the characteristic lengths of the material. Furthermore, the mesh dependency of the localized bands in the analysis of softening problems was eliminated in the present model. For the softening problems, massive iterations were usually needed with the classical elastoplastic methods and may not converge in some cases. Based on the parametric variational principle, the original nonlinear problem was transferred to a complementary problem, then the efficiency and convergence of the solution were greatly improved. Finally, several numerical examples demonstrate the validity of the proposed method. [ABSTRACT FROM AUTHOR]

An abstract of the article "Finite element analysis system for thermal problems based on SiPESC" by Yang Dong-Sheng and colleagues is presented.

This paper discusses the pretreatment with chitosan on wool, and then adds the additives of rare earth elements used in wool dyeing with Lanasol dyes. First through the two single factor and an orthogonal experiments results, experimental results show that wool treated with chitosan and added to rare earth elements can obtain higher dyeing percent ration and deeper colors. We could achieve one of the best experimental results: in the pretreatment part chitosan 2 g/L, pH value 4, the pretreatment temperature 35 °C ,time 30 mm; Lanasol dye 2% (owf) , rare earth 0. 1% (owf) , pH value 4. 5, 80 50 mm. The way makes low-temperature dyeing and energy conservation come true , improves the strength of wool and the balance of dyeing. [ABSTRACT FROM AUTHOR]

During the war, the time windows is the essential property of combat missions. Combining with the development of battle plan, this paper illustrated the inherent hierarachy of it and relationships between task and plan in every command level; on the topic of the joint operational plans, for the first established mathematical model with time windows, and solved it by using extended multidimensional dynamic list scheduling (EMDLS). Experimental results suggest that the solution is reasonable and practicable. [ABSTRACT FROM AUTHOR]

The numerical method for the steady Navier-Stokes equations is studied to solve the inner flow field of the nozzle. The N-S computing technique with the slip-boundary theory is developed for the near-continuum slip flow near the nozzle exit. The DSMC method for the flow of axial symmetry is studied to simulate the core plume, the DSMC scheme for the simulation of three-dimensional far-field plume flow is developed, and the DSMC method is studied for multi-species mixture plume. Then, the multiregion decomposing and coupling technique is developed to solve the inside and outside flow of the thruster including the near-field, far-field, backflow and gas-surface infected regions. As a result, the numerical simulation method has been presented to compute the gas-fired mixture plume from the attitude-control thruster of the satellite and the impinging contamination on the surface of the solar array panel and satellite. To study the contamination effects produced by the five-species mixture plume from two representative attitude-control thrusters installed in different locations of the satellite in orbit, the present method is adopted to simulate the nozzle inflow, tremendous plume flowfield of five-species mixture including the impinging contamination of the particles from the gas-fired plume. The flowfield properties of the gas-fired plume from the attitude-control thrusters are obtained, the related computed results are compared and analyzed with the experimental measurement and other theoretical calculation, which validates the reliability of the present numerical method. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the expression and significance of discoidin domain receptor 1 (DDR1) in salivary gland mucoepidermoid carcinoma (MEC)., Methods: Immunohistochemical and Western blot method were used to detect the expression of DDR1 in MEC M3SP2 and MC3 cell lines. Immunohistochemical method was used to detect the expression of DDR1 in 58 MEC and 20 normal salivary gland tissues. SPSS 13.0 software package was used for statistical analysis., Results: The positive expression rate of DDR1 in salivary gland MEC tissues was 79.3%, significantly higher than 10.0% in normal salivary gland tissues (P<0.01). High expression of DDR1 was not related to clinicopathological parameters of MEC(P>0.05). The expression of DDR1 was positive in MEC M3SP2 and MC3 cell lines., Conclusions: DDR1 may play an important role in carcinogenesis and progress of salivary gland MEC.

Purpose: To discuss the clinical and pathological characteristics and management of parotid gland cyst., Methods: Forty-five resected samples of parotid gland tumors were selected from Shengjing Hospital of China Medical University from January 2000 to June 2014 whose postoperative pathological diagnosis were parotid gland cysts. The clinico-pathological characteristics in different types of parotid gland cysts were analyzed., Results: Of 45 cases of parotid gland cyst, 25 were males, 20 were females. The median age was 51 years old. 21 cases were located on the left side of parotid gland, while 24 on the right side. The main clinical symptom was painless swelling in parotid gland region. The sizes varied from 0.8 cm×0.6 cm×0.5 cm to 10 cm×2.8 cm×0.6 cm. Nine cases were accompanied with pain, and 36 without. 4 cases were seen with lymph node enlargement, and 41 without pain. The main treatment modality was simple resection of cyst without any injury of facial nerve. No recurrence was seen after following up for 1-10 years. Of the 45 postoperative histopathological results, 29 cases (64.4%) were simple cysts, 9 cases (20.0%) were polycystic disease cysts, and 7 cases (15.6%) were lymphoepithelial cysts. Besides the above-stated pathological manifestations, some non-specific microscopic changes were accompanied with parotid gland cysts, including tumor-like hyperplasia of fibrous tissue, inflammations, calcifications, synovial cyst-like changes, foreign-body giant cell reactions and granulomatous changes., Conclusions: The main symptom of parotid gland cyst is progressive enlargement, and simple resection of cyst is the first-line treatment without facial nerve injury or reoccurrence. The main pathological classifications are simple cysts,lymphoepithelial cysts and polycystic disease cysts.

Purpose: To investigate the expressions of discoidin domain receptor 1(DDR1) and matrix metalloproteinase 2(MMP2) in salivary gland adenoid cystic carcinoma (SACC) and discuss their significance and correlations with clinicopathological parameters., Methods: SP immunohistochemical method was used to detect the expressions of DDR1 and MMP2 in 54 samples of SACC and 30 normal salivary gland samples. SPSS 13.0 software package was used for statistical analysis., Results: The positive expression rate of DDR1 in SACC was 87.0%, which was significantly higher than that in normal salivary gland tissues (10.0%, P<0.01). The positive expression of DDR1 was related with neural invasion and lymph node metastasis (P<0.05). The positive expression rate of MMP2 was 68.5% in SACC, which was significantly higher than that in normal group(13.3%, P<0.01). The expression of DDR1 was positively correlated with MMP2 by Spearman rank analysis(r=0.332, P<0.05)., Conclusions: High expressions of DDR1 and MMP2 correlate with carcinogenesis and progress of SACC. Supported by Research Fund of Science and Technology Project of Liaoning Province (2012225100).

Objective: To study the dynamic characteristics of serotonin (5-HT), dopamine (DA) and their metabolin changes in brain during the development of exercise-induced central fatigue., Methods: Coupling of microdialysis and capillary electrophoresis-laser induced fluorescence detection method were used to continuously monitored the changes of DA, tryptophan (Trp), tyrosine (Tyr), 5-HT and 5-hydroxyindoleacetic acid (5-HIAA) in striatum extracellular fluid during the exhaustive exercise and recovery time., Results: The concentrations of Trp, 5-HT, 5-HIAA in striatum extracellular fluid had no remarkable changes in the early time of exercise (P < 0.05), while they significantly increased during the later time of exercise and whole recovery time (P < 0.05, P < 0.01). The concentrations of DA and Tyr significantly increased over basal level in the later exercise time, exhaust and recovery time (P < 0.05, P < 0.01). DA/5-HT significantly increased in the initial time of exercise (P < 0.05, P < 0.01), while decreased during the later exercise time, the nadir occurred at 15 minutes before rats exhausted. DA/5-HT slightly recovered back to basal level during the recovery time, and there was no significant difference during later exercise, exhausted and recovery time compared with basal level (P < 0.05)., Conclusion: The changes of DA and 5-HT in striatum have phase characteristics. Both of them significantly increase during the development of exercise-induced fatigue. However, the 5-HT plays the dominant role in the dynamic changes of them.