1,171 research outputs found

    The collaboration of noise reduction and human vision system models for a visible watermarking algorithm

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    ABSTRACT A novel visible watermarking algorithm based on noise reduction and Human Visible System (HVS) model approach is presented in this study. In order to get the best tradeoff between the embedding energy of watermark and the perceptual translucence for visible watermark, the composite coefficients using global and local characteristics of the host image in the discrete wavelet transform (DWT) domain is considered. The application of the perceptual model of contrast-sensitive function (CSF) with the noise reduction of the visibility thresholds for HVS in DWT domain achieves the goal of fine tuning of the perceptual weights according to the basis function amplitudes for the best quality of perceptual translucence. Instead of three types of block classification-textures, edges and smooth areas, the computation of Noise Visibility Function (NVF) characterizes the local image properties to determine the optimal watermark locations and strength at the watermark embedding stage. The experimental results demonstrate that the proposed technique improves the PSNR values and visual quality than the CSF only based algorithms

    Use of an open-source CAD software program and additive manufacturing technology to design and fabricate a definitive cast for retrofitting a crown to an existing removable partial denture

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    This technical report describes a digital process for designing and fabricating a stackable definitive cast and die system to facilitate the fabrication of a new surveyed crown to retrofit to a removable partial denture (RPD). By using an open-source computer-aided design (CAD) software program, this technique provides an economical option for dental clinicians and laboratory technicians to use intraoral scans and design a stackable definitive cast and die system with minimal financial investment in the CAD software. In addition, this technique provides the advantage of a conventional indirect technique in that it can create a definitive cast with an RPD clasp assembly ready for the dental technician to properly contour the new surveyed crown, but without the need for the patient to be without the RPD during the process

    Sonographic Detection of Pseudoaneurysm in Vascular Injury in Emergency Department

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    A 31-year-old man suffered from a stab wound to the lower extremity. The patient had a hard sign of a vascular injury (a diminished distal pulse) and therefore probably should have undergone operative repair, but refused. One week later, he returned to our emergency department with a painful right thigh swelling. Bedside sonography was used to detect a pseudoaneurysm. Emergency sonography is a fast, non-invasive, and rapid decision-making approach in emergency practice

    Genotoxicity Assessment of Multispecies Probiotics Using Reverse Mutation, Mammalian Chromosomal Aberration, and Rodent Micronucleus Tests

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    Genotoxicity assessment is carried out on freeze dried powder of cultured probiotics containing Lactobacillus rhamnosus LCR177, Bifidobacterium adolescentis BA286, and Pediococcus acidilactici PA318. Ames tests, in vitro mammalian chromosome aberration assay, and micronucleus tests in mouse peripheral blood are performed. For 5 strains of Salmonella Typhimurium, the Ames tests show no increased reverse mutation upon exposure to the test substance. In CHO cells, the frequency of chromosome aberration does not increase in responding to the treatment of probiotics. Likewise, the frequency of micronucleated reticulocytes in probiotics-fed mice is indistinguishable from that in the negative control group. Taken together, the toxicity assessment studies suggest that the multispecies probiotic mixture does not have mutagenic effects on various organisms

    Plasmonic Circular Nanostructure for Enhanced Light Absorption in Organic Solar Cells

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    This study attempts to enhance broadband absorption in advanced plasmonic circular nanostructures (PCN). Experimental results indicate that the concentric circular metallic gratings can enhance broadband optical absorption, due to the structure geometry and the excitation of surface plasmon mode. The interaction between plasmonic enhancement and the absorption characteristics of the organic materials (P3HT:PCBM and PEDOT:PSS) are also examined. According to those results, the organic material's overall optical absorption can be significantly enhanced by up to ~51% over that of a planar device. Additionally, organic materials are enhanced to a maximum of 65% for PCN grating pitch = 800 nm. As a result of the PCN's enhancement in optical absorption, incorporation of the PCN into P3HT:PCBM-based organic solar cells (OSCs) significantly improved the performance of the solar cells: short-circuit current increased from 10.125 to 12.249 and power conversion efficiency from 3.2% to 4.99%. Furthermore, optimizing the OSCs architectures further improves the performance of the absorption and PCE enhancement

    Suppression of inducible cyclooxygenase and nitric oxide synthase through activation of peroxisome proliferator-activated receptor-γ by flavonoids in mouse macrophages

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    AbstractPeroxisome proliferator-activated receptor (PPAR)γ transcription factor has been implicated in anti-inflammatory response. Of the compounds tested, apigenin, chrysin, and kaempferol significantly stimulated PPARγ transcriptional activity in a transient reporter assay. In addition, these three flavonoids strongly enhanced the inhibition of inducible cyclooxygenase and inducible nitric oxide synthase promoter activities in lipopolysaccharide-activated macrophages which contain the PPARγ expression plasmids. However, these three flavonoids exhibited weak PPARγ agonist activities in an in vitro competitive binding assay. Limited protease digestion of PPARγ suggested these three flavonoids produced a conformational change in PPARγ and the conformation differs in the receptor bound to BRL49653 versus these three flavonoids. These results suggested that these three flavonoids might act as allosteric effectors and were able to bind to PPARγ and activate it, but its binding site might be different from the natural ligand BRL49653

    A naturally occurring carotenoid, lutein, reduces PDGF and H2O2 signaling and compromised migration in cultured vascular smooth muscle cells

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    <p>Abstract</p> <p>Background</p> <p>Platelet-derived growth factor (PDGF) is a potent stimulator of growth and motility of vascular smooth muscle cells (VSMCs). Abnormalities of PDGF/PDGF receptor (PDGFR) are thought to contribute to vascular diseases and malignancy. We previously showed that a carotenoid, lycopene, can directly bind to PDGF and affect its related functions in VSMCs. In this study we examined the effect of the other naturally occurring carotenoid, lutein, on PDGF signaling and migration in VSMCs.</p> <p>Methods</p> <p>Western blotting was performed to examine PDGF and H<sub>2</sub>O<sub>2 </sub>signaling. Flowcytometry was used to determine PDGF binding to VSMCs. Fluorescence microscopy was performed to examine intracellular ROS production. Modified Boyden chamber system (Transwell apparatus) was used for migration assay.</p> <p>Results</p> <p>Lutein reduced PDGF signaling, including phosphorylation of PDGFR-β and its downstream protein kinases/enzymes such as phospholipase C-γ, Akt, and mitogen-activated protein kinases (MAPKs). Although lutein possesses a similar structure to lycopene, it was striking that lutein inhibited PDGF signaling through a different way from lycopene in VSMCs. Unlike lycopene, lutein not only interacted with (bound to) PDGF but also interfered with cellular components. This was evidenced that preincubation of PDGF with lutein and treatment of VSMCs with lutein followed by removing of lutein compromised PDGF-induced signaling. Lutein reduced PDGF-induced intracellular reactive oxygen species (ROS) production and attenuated ROS- (H<sub>2</sub>O<sub>2</sub>-) induced ERK1/2 and p38 MAPK activation. A further analysis indicated lutein could inhibit a higher concentration of H<sub>2</sub>O<sub>2</sub>-induced PDGFR signaling, which is known to act through an oxidative inhibition of protein tyrosine phosphatase. Finally, we showed that lutein functionally inhibited PDGF-induced VSMC migration, whereas its stereo-isomer zeaxanthin did not, revealing a special action of lutein on VSMCs.</p> <p>Conclusions</p> <p>Our study reveals a differential action mechanism of lutein from other reported caroteinoids and suggests a possible beneficial effect of lutein but not zeaxanthin on prevention of vascular diseases.</p

    A case of acute appendicitis with Vibrio fluvialis peritonitis

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    AbstractHuman infections caused by Vibrio fluvialis are rarely reported. The most common clinical presentation of V. fluvialis infection is acute gastroenteritis with diarrhea. Reported extra-intestinal infections caused by V. fluvialis have included bacteremia, hemorrhagic cellulitis and cerebritis. Peritonitis is an uncommon clinical presentation of Vibrio infections, and most cases have occurred in patients receiving peritoneal dialysis or those with liver cirrhosis. Herein, we report the first case of acute appendicitis with V. fluvialis peritonitis
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