11,410 research outputs found

    Extraction of 3D vortex structures from a turbulent puff in a pipe using two-color illumination and flakes

    Get PDF
    A novel visualization technique was proposed to extract the three-dimensional vortex structure of a turbulent puff, which is a local turbulence event that is observed in pipe flows at relatively low Reynolds numbers. The technique is based on multi-color illumination of microscopic flakes that are suspended in the flow, which makes structural visualization more informative than conventional monochrome approaches. A special optical arrangement of two laser sheets, colored green and blue, was established for the circular pipe. Based on an image analysis sequence, the internal structure of the puff is reconstructed as a cross-sectional temporal 3D image consisting of voxels with unicolor degrees between green and blue, where an individual single vortex is extracted as a pair of two-color stripes. This allows quantification of the azimuthal wavenumber of the vortical structure that characterizes the puff. The wavenumber results agreed well with the results of previous studies, thus supporting the applicability of the proposed visualization technique.

    Query Augmentation Using Search Engine Results to Improve Answers Generated by Large Language Models

    Get PDF
    Large Language Model (LLM) and Generative Pre-trained Transformer (GPT) technology has the ability to generate responses to questions provided in text format. While such technology produces text content with plausible answers to a given question, it is difficult to judge the trustworthiness of the generated answers. It has been shown that answers generated by such technology may not always be factually accurate. This disclosure describes automated techniques to improve the credibility and confidence of machine-generated answers by using results from a search engine. Per the techniques, search results corresponding to a user input query are used to generate an augmented query that is provided as input to an LLM. Such augmentation adds context and can improve the quality and reliability of answers generated by the LLM. Further, the techniques can also be utilized to add citations to the generated answer and to indicate a confidence level in the generated answer

    Labisia pumila extract protects skin cells from photoaging caused by UVB irradiation

    Get PDF
    Labisia pumila (Myrsinaceae), known as "Kacip Fatimah," has been used by many generations of Malay women to induce and facilitate child birth as well as a post partum medicine. However, its topical application on skin has not been reported yet. In this study, we have focused on the anti-photoaging effects of L. pumila. Extract of L. pumila was first analyzed for their antioxidant activities using DPPH (2,2-diphenyl-1-picrylhydrazyl) since UV irradiation is a primary cause of reactive oxygen species (ROS) generation in the skin. The 50% free radical scavenging activity (FSC(50)) of L. pumila extract was determined to be 0.006%, which was equal to that produced by 156 microM ascorbic acid. TNF-alpha and cyclooxygenase (COX-2) play a primary role in the inflammation process upon UV irradiation and are known to be stimulated by UVB. Treatment with L. pumila extract markedly inhibited the TNF-alpha production and the expression of COX-2. Decreased collagen synthesis of human fibroblasts by UVB was restored back to normal level after treatment with L. pumila extract. On the other hand, the enhanced MMP-1 expression upon UVB irradiation was down regulated by L. pumila extract in a dose-dependent manner. Furthermore, treatment of normal keratinocytes with L. pumila extract attenuated UVB-induced MMP-9 expression. These results collectively suggest L. pumila extract has tremendous potential as an anti-photoaging cosmetic ingredient

    Optimal design of quadratic electromagnetic exciter

    Get PDF
    The vibration acceleration of collecting plates, which is the core indicator of rapping performance in an electrostatic precipitator’s vibration rapping process, is determined by magnetic force of a quadratic electromagnetic exciter. The larger exciter provides the larger magnetic force, but the installation space for the exciter is limited. Accordingly, this paper presents the optimal design of quadratic electromagnetic exciter to maximize the magnetic force with constraint that the size of exciter is constant. A design optimization problem was formulated in order to find the quadratic electromagnetic exciter shape parameters that maximized the magnetic force. The magnetic force of the quadratic electromagnetic exciter was evaluated using the commercial electromagnetic analysis software “MAXWELL”. For efficient design, we employed metamodel-based design optimization using design of experiments (DOE), metamodels, and an optimization algorithm equipped in PIAnO (Process Integration, Automation and Optimization), a commercial PIDO (Process Integration and Design Optimization) tool. Using the proposed design approach, the optimal magnetic force was increased by 1.68 % compared to the initial one. This result demonstrates the effectiveness of the established analysis and design procedure for the quadratic electromagnetic exciter

    Anti-aging activities of Pyrus pyrifolia var culta plant callus extract

    Get PDF
    Purpose: To investigate the anti-aging properties of callus extract from Pyrus pyrifolia var. culta with skin regeneration and lightening activities.Methods: Callus extract of P. pyrifolia var. culta was produced on Murashige and Skoog (MS) medium supplemented with picloram, followed by extraction of the callus biomass in phosphate-buffered saline. The anti-oxidant activity of the extract was assessed using the DPPH free radical-scavenging assay. Inhibition of skin pigmentation by callus extract was evaluated by measuring the melanogenesis of melanoma cells. The skin-regenerating efficacy of the extract was evaluated in terms of its ability to promote procollagen synthesis and fibroblast cell proliferation.Results: The callus extract, at 10 mg/mL, exhibited 78.7 % free radical-scavenging activity, equivalent to that exhibited by 500 μM ascorbic acid. The 1 mg/mL extract solution afforded a 1.4-fold greater reduction in melanocyte melanin than did a 1 mg/mL arbutin solution. Fibroblast cells treated with 5 mg/mL callus extract exhibited 127 % higher levels of proliferation and 2.0-fold higher levels of procollagen type I C-peptide synthesis, respectively, compared with the untreated controls.Conclusion: These findings suggest that the callus extract of P. pyrifolia var. culta may be useful as a source of anti-aging cosmetic components with skin lightening and regenerating activities.Keywords: P. pyrifolia var. culta, Anti-aging, Callus extract, Skin lightening, Anti-tyrosinase activity, Melanogenesis, Wound recovery, Procollagen type I C-peptide synthesi
    corecore