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We present a detailed derivation of the Reynolds equation and its corresponding energy equation for three-dimensional, steady, laminar, compressible flows of single-phase Navier-Stokes fluids in thrust bearings. These equations are shown to be valid over most of the dense and supercritical gas regime except for the vicinity of the thermodynamic critical point. It is shown that the primary thermodynamic function governing the lubrication flow of high-pressure gases is the effective bulk modulus defined as the ratio of the bulk modulus to the shear viscosity. Numerical solutions to our Reynolds equation are obtained using a finite difference scheme for both moderate and high-speed flows. Approximate solutions to our Reynolds equation for high-speed flows are also derived through a perturbation analysis. It is found that boundary layers form on three out of four edges of the thrust pad. At the inner and outer radii of the pad, the flow is governed by a nonlinear heat equation. As the main flow leaves the pad, the flow is governed by a nonlinear relaxation equation. These three boundary layer solutions are rendered consistent by the construction of boundary layer solutions in the corner regions. A composite solution is developed which provides a single approximation and has the same accuracy as the individual approximations in their respective regions of validity. [ABSTRACT FROM AUTHOR]

We derive the Reynolds equation corresponding to steady, laminar, two-dimensional, compressible flows of single-phase Navier-Stokes fluids in a thin gap between a stationary surface and one translating with constant speed. The thermodynamic state of the fluid is taken to be in the dense and supercritical gas regimes. The equation of state is a well-known cubic equation, and the shear viscosity and thermal conductivity are taken to depend on density and temperature. Thermal boundary conditions are taken to include those for constant-temperature and adiabatic walls. The flow is seen to be governed by both the speed number and a single thermodynamic parameter referred to as the effective bulk modulus. Numerical solutions to the Reynolds equation are compared to those of the full Navier-Stokes equations. It is shown that the Reynolds equation breaks down in the vicinity of the thermodynamic critical point. Furthermore, we show that energy convection is negligible whenever the Reynolds equation is valid which enables us to present new explicit solutions for the temperature distributions. [ABSTRACT FROM AUTHOR]

Efficient intersection queries are important for ray tracing. However, building and maintaining the acceleration structures is demanding, especially for fully dynamic scenes. In this paper, we propose a quantized intersection framework based on compact voxels to quantize the intersection as an approximation. With high-resolution voxels, the scene geometry can be well represented, which enables more accurate simulation of global illumination, such as detailed glossy reflections. In terms of memory usage in our graphics processing unit implementation, voxels are binarized and compactly encoded in a few 2D textures. We evaluate the rendering quality at various voxel resolutions. Empirically, high-fidelity rendering can be achieved at the voxel resolution of 1 K3 or above, which produces images very similar to those of ray tracing. Moreover, we demonstrate the feasibility of our framework for various illumination effects with several applications, including first-bounce indirect illumination, glossy refraction, path tracing, direct illumination, and ambient occlusion. [ABSTRACT FROM AUTHOR]

Clustering analysis has been widely applied in the area of market segmentation. Conventional research usually uses the multivariate analysis method. Recently, due to promising results of computational intelligence techniques in engineering, they arc also considered for market segmentation. Among them, genetic algorithms (Gas) are theoretically and empirically found to provide globally near-optimal solutions for various complex optimization problems. Because GA is good at searching, it can cluster the data according to their similarities. In addition, artificial neural networks also have high performance in both engineering and management. Hence, this research proposes a novel 2-stage method, which first uses self-organizing feature maps (SOMs) to determine the number of clusters and then employs a GA-based clustering method to find the Final solution (it is defined as S + G in this research). The results of simulated data via a Monte Carlo study show that the proposed method out-performs the other 2 methods: K means, which uses SOM to determine the number at clusters, and SOM followed by K means, based on both within-cluster variations (SSW) and the number of misclassifications. To further verity the proposed approach, a real-world problem, wireless telecommunications industry market segmentation, is employed. The results also show that the proposed method had has the lowest SSW among the 3 methods. [ABSTRACT FROM AUTHOR]

Polyamines, such as putrescine, spermidine and spermine, are essential for the regulation of cell proliferation and differentiation in most organisms. Spermidine synthase catalyzes the transfer of the aminopropyl group from decarboxylated S-adenosylmethionine to putrescine in the biosynthesis of spermidine. In this study, spermidine synthase of Helicobacter pylon has been overexpressed in Escherichia coli and purified. Two kinds of spermidine synthase crystals were obtained. One belongs to the monoclinic P21 space group, with unit-cell parameters a = 62.78, b = 58.24, c = 74.28 Å, β = 90.9°, and the other belongs to the orthorhombic C2221 space group, with unit-cell parameters a = 100.43, b = 128.55, c = 143.60 Å. [ABSTRACT FROM AUTHOR]

The majority of breast cancer patients are resistant to chemotherapy or radiotherapy due to the down-regulation or lack of caspase-3 expression. Capsaicin was found to inhibit cancer cell growth in caspase-3-deficient human breast cancer cells. This study aimed to investigate the growth-inhibitive effect of capsaicin and its mechanisms in human breast cancer cell lines, MCF-7 and BT-20. The results showed that cell viability decreased in a dose-dependent manner in both the caspase-3-deficient and non-deficient cells through inducing cell apoptosis and arresting the cell cycle in the S phase. Capsaicin significantly decreased mitochondria membrane potential, induced the cleavage of PARP-1, and decreased procaspase-7 expression in both cells. Apoptosis-inducing factor (AIF) was distinctly released from mitochondria and translocated into the cytoplasm and nucleus in MCF-7 cells (52.9%), but not in BT-20 cells (2%) after treatment with 200 μM of capsaicin for 24 hours. Capsaicin inhibited breast cancer cell growth through inducing cell apoptosis and cell cycle arrest in the S phase. This apoptotic effect could be induced through the mitochondrial pathway, and PARP-1 subsequently cleaved by activation of caspase-7. The application of capsaicin in clinical therapy could be useful for breast cancer patients.

Metastatic meningococcal endophthalmitis, although rare, is a rapidly progressive and sight-threatening infection. We present a 10-month-old infant with meningococcal meningitis who developed unilateral metastatic endophthalmitis. If patients develop a sepsis-like picture with cloudy cornea and purulent conjunctivitis, we have to consider the possibility of endophthalmitis and full ophthalmological evaluations are indicated. Treatment should be started as early as possible. The outcome of endophthalmitis is frequently permanent visual impairment. Endophthalmitis is a true medical emergency requiring early antibiotic therapy with full dose of antimicrobials to avoid morbidity and blindness.

In vivo and in vitro experiments are reported demonstrating that the catabolite repressor-activator (Cra) protein (formerly designated FruR) regulates expression of the cydAB operon of Escherichia coli encoding cytochrome d oxidase. The Fnr protein is required for Cra-mediated transcriptional control, but the ArcA protein antagonizes the response to Cra. The results establish that Fnr, ArcA, and Cra exert their effects in an interdependent fashion.