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This paper proposes a modified third generation non-dominated sorting genetic algorithm (mNSGA-III) to overcome the poor convergence of third generation non-dominated sorting genetic algorithm (NSGA-III) in handling discrete topology optimization. It uses the mNSGA-III for the structural optimization of a body-in-white (BIW) welding production platform. It proposes an advanced extreme point selection to stabilize the normalization of populations. It constructs the finite element model of BIW welding production platform. Using discrete topology optimization, it treats the total mass, maximum stress and z-direction displacements of several nodes of platform as objective functions. It developed a discrete topology optimization program by using MATLAB interfaced the commercial finite element code MSC.Nastran. Finally, it selected the design with appropriate layout in view of stiffness and strength of the structure. The optimal design conforms to the design standards and the total mass reduces by 30.1%. The results show that mNSGA-III gets a more stable optimization process and easy to converge when solving the multi-objective discrete topology optimization problems. The proposed method provides an applicable method for the optimization of giant steel structures and has great values for practical engineering problem.

The mesh morphing technology is applied to the retrofit design of a baseline car model in this paper. Specifically, according to the morphing scheme worked out, the geometric dimension of FE model for its body-in-white is changed to build the FE model for new car model efficiently, with its performance predicted by finite element analysis. The results indicate that with mesh morphing technology, the dependency of design on detailed CAE data and the time-consuming preparation activities for simulation can be avoided, with the lead time for car model development shortened and the development cost reduced, truly embodying the vision of 'CAE leads design'. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the anxiety and depression status of patients with nasal septum deviation before and after surgery, and explore the relationship between anxiety and depression and nasal symptoms., Method: By means of visual analogue scale (VAS) as the evaluation index of quality of life, self-rating anxiety scale (SAS) and self-rating depression scale (SDS) were used to analyze statuses before and after surgery. The 98 patients with nasal septum deviation were collected., Result: The preoperative SAS/SDS scores of the nasal septum deviation patients were higher than those of the national standards. The level of anxiety and depression were lower than the national norm after treatment. The patients of the normal and moderate SAS/SDS scores felt better after surgery. The patients of the severe SAS/SDS scores felt the symptoms improve poor., Conclusion: Doctors should pay attention to the application of the SAS/SDS in patients of nasal septum deviation. Surgeon should actively communicate with severe patients in psychological problems, and strictly control the surgical indication of such patients.

Objective: To investigate the inhibitive role of lentivirus mediated MMP-9 gene silence in the growth of laryngeal cancer xenografts., Method: The nude mouse model of laryngeal squamous carcinoma was established and RNA interference (RNAi) technic was used. Recombinant MMP-9-RNAi-Lentivirus was intratumoral injected while the empty vector lentivirus was taken as control. After the treatment, tumor inhibitive effect was observed and western-blot was used to test the expression of MMP-9 in the xenografts. Finally, the PCNA expression in xenografts were examined with immunohistochemistry to evaluate proliferation change of the Hep-2 cells., Result: The average tumor weight was (1.484 +/- 0.391) g in group treated with MMP-9-RNAi-Lentivirus which was significantly lower than that (2.618 +/- 0.465) g in the control group (P < 0.05). The average tumor volume was (1.177 +/- 0.270) cm3 in group treated with MMP-9-RNAi-Lentivirus which was significantly lower than that (2.034 +/- 0.366) cm3 in the control group (P < 0.05) and the tumor inhibitive rate was 43.32%. Western-blot showed there were 7 cases of xenografts with MMP-9 protein negative expression and the other 3 cases were tested with weak positive expression in the treated group xenografts. Whereas all the 10 cases of xenografts were tested with MMP-9 positive expression in the control group. Immunohistochemistry showed PCNA index in treated group was (55.41 +/- 8.77)% which was obviously lower than that (77.04 +/- 6.91)% in control group (P < 0.01)., Conclusion: The growth and proliferation of laryngeal cancer could be inhibited by recombinant MMP-9-RNAi-Lentivirus.

Objective: To study the effects of adenovirus-mediated tissue factor pathway inhibitor-2 gene on the invasion of laryngeal squamous cancer., Method: Ad-TFPI-2 was transfected into laryngeal squamous cancer (Hep-2) cell. Western-blot was used to test the TFPI-2 protein expression and Boyden Chamber experiment was used to examine the invasive ability of Hep-2 cells. Furthermore, the Ad-TFPI-2 infected Hep-2 cells were subcutaneously inoculated in nude mice and the tumor formation capability were observed., Result: Ad-TFPI-2 was identified correctly by endonuclease and sequencing and the virus titer was 2.8 x 10(13) PFU/L. In the Hep-2 cells of treated group, the TFPI-2 protein expression was increased while the invasive capability was descent. The tumor formation capability was also decreased in the treated group nude mouse model., Conclusion: TFPI-2 recombinant adenovirus can effectively inhibit the invasive capability of laryngeal squamous cancer.