21 research outputs found

    Development of a Sampling and Real-time PCR Method for the Quantitative Detection of Campylobacter spp. in Retail Chicken Meat Without DNA Extraction

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    Campylobacter food poisoning is caused by consumption of the contaminated foods, especially poultry meat. Continuous quantitative measurement of Campylobacter spp. in contaminated foods is crucial to develop preventive measures. We developed a direct-qPCR method for determining the viable cell counts of Campylobacter spp. using qPCR without DNA extraction from enriched food samples and a sampling method (the wrap procedure) in which the sample is wrapped in a sheet, different from the conventional homogenization procedure.The viable cell counts of Campylobacter spp. before and after enrichment of the samples sampled using the wrap and homogenization procedures from chicken samples inoculated with Campylobacter jejuni were determined using the culture method, and the cycle threshold (CT) values after enrichment were determined using the direct-qPCR. An enrichment regression equation was generated from the viable cell counts obtained before and after enrichment, and a direct-qPCR regression equation was generated from the CT values and viable cell counts obtained after enrichment, enabling the viable cell counts before enrichment to be estimated from the CT values.Estimated viable cell counts were similar for the culture method when sampled by the homogenization procedure, but lower for the wrap procedure. However, the detection rate of direct-qPCR was 37.5% for liver and 89.7% for breast fillet using the homogenization procedure, whereas using the wrap procedure, it was 100% for both samples.The detection rate of direct-qPCR for retail chicken was 30.4–35.7% for the homogenization procedure, and 85.7–100% for the wrap procedure. Colonies were observed using the culture method, but their quantification was difficult due to swarming or their low number. However, estimating viable cell counts using the combination of wrap procedure and direct-qPCR methods is possible.The developed method can provide baseline data for the risk assessment Campylobacter food poisoning

    Anomaly detection using Unsupervised Machine Learning for Grid computing site operation

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    A Grid computing site is composed of various services including Grid middleware, such as Computing Element and Storage Element. Text logs produced by the services provide useful information for understanding the status of the services. However, it is a time-consuming task for site administrators to monitor and analyze the service logs every day. Therefore, a support framework has been developed to ease the site administrator’s work. The framework detects anomaly logs using Machine Learning techniques and alerts site administrators. The framework has been examined using real service logs at the Tokyo Tier2 site, which is one of the Worldwide LHC Computing Grid sites. In this paper, a method of the anomaly detection in the framework and its performances at the Tokyo Tier2 site are reported

    Anomaly detection using Unsupervised Machine Learning for Grid computing site operation

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    A Grid computing site is composed of various services including Grid middleware, such as Computing Element and Storage Element. Text logs produced by the services provide useful information for understanding the status of the services. However, it is a time-consuming task for site administrators to monitor and analyze the service logs every day. Therefore, a support framework has been developed to ease the site administrator’s work. The framework detects anomaly logs using Machine Learning techniques and alerts site administrators. The framework has been examined using real service logs at the Tokyo Tier2 site, which is one of the Worldwide LHC Computing Grid sites. In this paper, a method of the anomaly detection in the framework and its performances at the Tokyo Tier2 site are reported

    Synchronized mesenchymal cell polarization and differentiation shape the formation of the murine trachea and esophagus

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    Tube morphogenesis is essential for internal-organ development, yet the mechanisms regulating tube shape remain unknown. Here, we show that different mechanisms regulate the length and diameter of the murine trachea. First, we found that trachea development progresses via sequential elongation and expansion processes. This starts with a synchronized radial polarization of smooth muscle (SM) progenitor cells with inward Golgi-apparatus displacement regulates tube elongation, controlled by mesenchymal Wnt5a-Ror2 signaling. This radial polarization directs SM progenitor cell migration toward the epithelium, and the resulting subepithelial morphogenesis supports tube elongation to the anteroposterior axis. This radial polarization also regulates esophageal elongation. Subsequently, cartilage development helps expand the tube diameter, which drives epithelial-cell reshaping to determine the optimal lumen shape for efficient respiration. These findings suggest a strategy in which straight-organ tubulogenesis is driven by subepithelial cell polarization and ring cartilage development
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