93 research outputs found
Relationships between Large-Scale Coherent Motions and Bursting Events in a Turbulent Boundary Layer
Scalar Transfer across a Turbulent/non-turbulent Interface in a Planar Jet
This fluid dynamics video is an entry for the Gallery of Fluid Motion of the
66th Annual Meeting of the APS-DFD. In this video, the scalar transfer across
the turbulent/non-turbulent (T/NT) interface in a planar jet is investigated by
using a direct numerical simulation. Visualization of the scalar flux across
the T/NT interface shows that the diffusive species premixed in the ambient
flow is transferred into the turbulent region mainly across the leading edge
(Here, the leading edge is the T/NT interface across which the turbulent fluid
turns into the non-turbulent fluid in the streamwise direction).Comment: The fluid dynamics video for an entry for the Gallery of Fluid Motion
of the 66th Annual Meeting of the APS-DFD is include
Direct Numerical Simulation of Turbulence with Scalar Transfer around Complex Geometries Using the Immersed Boundary Method and Fully Conservative Higher-Order Finite-Difference Schemes
Relationship of IE and oral conditions
Objectives
Infective endocarditis (IE) is a life-threatening infectious disease, but the pathogenesis of the disease remains uncertain. The objective of this study was to examine whether oral infectious conditions are associated with the occurrence of IE in valvular heart disease (VHD) patients.
Materials and Methods
A total of 119 periodontitis (P) patients with or without VHD were enrolled, and cross-sectional analyses were performed. Patients were classified as follows: 1) mild-to-moderate P without VHD, 2) mild-to-moderate P with VHD, 3) severe P without VHD, or 4) severe P with VHD. A total of 78 VHD patients were classified as 1) VHD without IE or 2) VHD with IE. Conditional logistic regression analysis was performed to compute the odds ratio (OR) and 95% confidence interval (CI).
Results
No significant differences were observed between patients with or without VHD in oral conditions. A significant increase in the percentage of alveolar bone loss in VHD patients with IE was observed compared with that of patients without IE. The ratio of both Porphyromonas gingivalis (Pg) IgG titer>1.68 and Pg fimA type II genotype in patients with IE was significantly higher than in patients without IE. There was a significant correlation between the occurrence of IE and clinical oral findings (number of remaining teeth: OR, 0.17; rate of alveolar bone loss>40%: OR, 11.8).
Conclusions
VHD patients with IE might have severe periodontitis compared with patients without IE, although further investigation will be needed because this is based on only 7 VHD patients with IE.
Clinical relevance
The patients with IE had fewer remaining teeth, more advanced bone resorption compared with those of patients without IE. These findings suggest a possible association between the occurrence of IE and periodontal infection
AJK2011-21015 CHARACTERISTICS OF THE SCALAR FIELD IN A TURBULENT LIQUID JET AND A FUNDAMENTAL STUDY ON THE MICRO SCALE CONCENTRATION MEASUREMENTS BY THE OPTICAL FIBER LIF METHOD
ABSTRACT In this study, the characteristics of the scalar field in an axisymmetric turbulent water jet are investigated experimentally. In the experiments, the axial velocity, the concentration of the dye solution and the temperature of the fluid are measured by the hot-film probe, the fiber sensor and the cold-firm probe, respectively. In particular, the difference of statistics between scalars (concentration and temperature) with the different molecular diffusion coefficients is discussed. The Schmidt number of the diffusing matter is 3,800, and the Prandtl number of temperature is 7. As regarding the mean values, the r.m.s values and distribution of PDF, we cannot find any difference between the concentration field and temperature field. However, in the spectrum, it is found that the temperature spectrum shows the -5/3 law almost in the same range as the velocity spectrum, on the other hand, the concentration spectrum shows the -5/3 law in the wider range than the velocity spectrum. This means that the shape of spectrum depends on the diffusion coefficient. In order to make the higher resolution measurement of concentration, a new optical probe based on the LIF method is designed. This probe consists of the two optical fibers, the tip of which is processed like the shape of a lens. By the effect of lens, the laser beam can be focused on the narrower area in comparison with the past LIF measurements. In the present design, the width of focus of laser beam is set to 0.6 micrometers, and the focal length is set to 7.3mm. It is shown that this probe has the resolution less than the Batchelor scale at in the condition of present jet diffusion field (d=4mm, Re=20,000). Further, a new system to adjust the position of the optic fiber probe exquisitely is developed. INTRODUCTION There are many practical problems in the industrial and natural flow fields that the diffusing matter are mixed. In this study, we pay a special attention to the diffusion fields of scalars (concentration and temperature) in the turbulent liquid jet. In the liquid phase, it is usually known that the Schmidt number of the diffusing matter (or the Prandtl number in case of temperature) is larger than 1, so that the scalar fields have been crucially influenced by the velocity field. In this case, it is useful to investigate the relations between the velocity and scalar statistics to understand the mixing process of the scalar in the turbulent liquid flows. With regard to the measurements of high Schmidt number matter, the concentrations of the fluorescent dye or the kalium chloride have been often measured by Laser-Induced Fluorescence (LIF) method or the electrode method. However seeing the past reports, in case of the flows with the mean shear, there are still large scattering of the data for the scalar statistics, and so the reliable turbulent statistics are keenly required. On the other hand, the similarity theory of turbulent scalar field shows that for the scalar field of high Schmidt number and high Reynolds number, there exist the statistical universal ranges called the "viscous convective subrange" and the "viscous diffusive subrange" in the space smaller than the Kolmogorov scale (which is the smallest velocity fluctuatio
Development of a novel data mining tool to find cis-elements in rice gene promoter regions
<p>Abstract</p> <p>Background</p> <p>Information on more than 35 000 full-length <it>Oryza sativa </it>cDNAs, together with associated microarray gene expression data collected under various treatment conditions, has made it feasible to identify motifs that are conserved in gene promoters and may act as <it>cis</it>-regulatory elements with key roles under the various conditions.</p> <p>Results</p> <p>We have developed a novel tool that searches for <it>cis</it>-element candidates in the upstream, downstream, or coding regions of differentially regulated genes. The tool first lists <it>cis-</it>element candidates by motif searching based on the supposition that if there are <it>cis-</it>elements playing important roles in the regulation of a given set of genes, they will be statistically overrepresented and will be conserved. Then it evaluates the likelihood scores of the listed candidate motifs by association rule analysis. This strategy depends on the idea that motifs overrepresented in the promoter region could play specific roles in the regulation of expression of these genes. The tool is designed so that any biological researchers can use it easily at the publicly accessible Internet site <url>http://hpc.irri.cgiar.org/tool/nias/ces</url>. We evaluated the accuracy and utility of the tool by using a dataset of auxin-inducible genes that have well-studied <it>cis-</it>elements. The test showed the effectiveness of the tool in identifying significant relationships between <it>cis-</it>element candidates and related sets of genes.</p> <p>Conclusion</p> <p>The tool lists possible <it>cis-</it>element motifs corresponding to genes of interest, and it will contribute to the deeper understanding of gene regulatory mechanisms in plants.</p
Self-assembled monolayer of light-harvesting core complexes of photosynthetic bacteria on an amino-terminated ITO electrode
Light-harvesting antenna core (LH1-RC) complexes isolated from Rhodospirillum rubrum and Rhodopseudomonas palustris were successfully self-assembled on an ITO electrode modified with 3-aminopropyltriethoxysilane. Near infra-red (NIR) absorption, fluorescence, and IR spectra of these LH1-RC complexes indicated that these LH1-RC complexes on the electrode were stable on the electrode. An efficient energy transfer and photocurrent responses of these LH1-RC complexes on the electrode were observed upon illumination of the LH1 complex at 880 nm
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