Optimal design of a dynamic absorber using polymer-laminated steel sheets

An optimal design of dynamic absorber was made in this study by using polymer-laminated steel sheets consisting of two steel sheets bounded with a polymeric layer. Based on the optimally turned and damped dynamic vibration absorber derived by Den Hartog [1], the thickness of constraining layers and interlayer could be obtained by employing the RKU model. In approaching the optimal loss factor of the laminates, this design problem has been formulated as a nonlinear constrained minimization problem, and solved through the usage of an interior penalty function method. Also, the characteristics of a dynamic absorber were discussed, with its design having a more effective vibration damping capability on a vibration system.     

Flow-cytometric detection of the RI alpha subunit of type I cAMP-dependent protein kinase in human cells

cAMP-dependent protein kinase (PKA) is composed of two genetically distinct catalytic (C) and regulatory (R) subunits. There are two different classes of PKA, designated as type I and type II, which contain distinct R subunits (RI or RII, respectively) but share a common C subunit. Enhanced expression of type I PKA has been correlated with cell proliferation and neoplastic transformation. Detection of the different PKA subunits is usually performed by photoaffinity labeling with 8-N3-32P-cAMP or by radioimmunolabeling techniques. Both techniques are time consuming and require a high number of cells and the use of radioactive reagents. Using the MCF-10A normal human mammary cell line infected with a recombinant retroviral vector containing the human RI alpha gene (MCF-10A RI alpha), we have developed a flow-cytometric assay to detect the intracellular content of RI alpha protein in human cells. MCF-10A and MCF-10A RI alpha cells were fixed in 1.5% paraformaldehyde at 37 degrees C for 15 min and permeabilized by methanol and acetone (1:1) at -20 degrees C for 5 min before staining with a specific IgG2a MoAb followed by a FITC-conjugate rabbit-anti mouse IgG. This procedure was also successfully utilized to recognize RI alpha protein content in human peripheral blood lymphocytes. Flow-cytometric detection of the RI alpha subunit in human cells is feasible and allows the study of the role of type I PKA in cell growth and neoplastic transformation.     

Bumper shape design for pedestrian safety

The main cause of leg injuries is the bumper during car-pedestrian accidents. Bumper geometry and bumper material have the greatest effect on pedestrian leg injury. The first objective of this study is to evaluate the effects of bumper shape on pedestrian leg injuries. This study uses three bumper shapes on three car models to evaluate the effects of bumper geometry on pedestrian leg injury: A Ford Taurus, Dodge Intrepid, and Dodge-Neon. Then, based on the results of the impact between legform and bumper, this study chooses the best bumper shape that results in the least injury to the pedestrian’s leg. The second objective of this study is to design a new bumper. Using some conclusions regarding the effects of bumper shape on the pedestrian leg injuries, a new pedestrian-friendly bumper was designed. This bumper satisfies EEVC/WG17 safety requirements regarding pedestrian leg injuries. The analyzed models and results obtained could help evaluate pedestrian friendliness of a vehicle and guide the future designing and development of pedestrian friendly vehicle technologies.

     

Optimum design of dome contour for filament-wound composite pressure vessels based on a shape factor

Filament-wound composite pressure vessels are an important type of high-pressure container that is widely applied in the commercial and aerospace industries. This study investigates the optimum design of dome contours for filament-wound composite pressure vessels, subjected to geometrical limitations, winding condition, and the Tsai–Wu failure criterion and maximizing shape factor, the feasible direction method being employed. An actual design example, presented by Fukunaga et al. [19], is adopted to study the optimum dome contour using the present method. Results reveal that the dome contours using the present method, Fukunaga et al.’s method and the netting method can be approximated using elliptic curves, and that the depth is the major parameter for optimizing the design of dome contour, and the dome, designed using the present method has stronger structure and greater internal volume than those designed using other approaches. Results reveal that the present method is usable for the optimum design of dome contours for filament-wound composite pressure vessels.     

Protein kinase A-directed antisense restrains cancer growth: sequence-specific inhibition of gene expression

Increased expression of the RI alpha subunit of cAMP-dependent protein kinase type I has been shown in human cancer cell lines, in primary tumors, in cells after transformation, and in cells upon stimulation of growth. The sequence-specific inhibition of RI alpha gene expression by an antisense oligodeoxynucleotide results in the differentiation of leukemia cells and growth arrest of cancer cells of epithelial origin. A single-injection RI alpha antisense treatment in vivo also causes a reduction in RI alpha expression and inhibition of tumor growth. Tumor cells behave like untransformed cells by making less protein kinase type I. The RI alpha antisense, which produces a biochemical imprint for growth control, requires infrequent dosing to restrain neoplastic growth in vivo.     

A large deformation elastic-plastic dynamic analysis of square plate and spherical shell subjected to shock loadings

Based on Bathe's methodology and Yuan's formulation, a large deformation elastic-plastic transient dynamic finite element method is proposed for shock loading dynamic analysis on simple local structure, such as square plate and spherical shell. The verification of the adopted method shows good agreement with related literature. The proposed method is then extended to study strong shock loading problems on local structure. The displacement/acceleration time histories with plastic zone spread phenomenas are shown in several interesting figures.