19 research outputs found

    A New Risk Evaluation Model for Safety Management on an Entire Ship Route

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    In this paper, we introduce a new risk evaluation model for evaluating the navigation safety zone for an entire ship route. This model considers a new algorithm to determine the navigational safety zone in real-time, and also takes the navigation officers’ perception while navigating a ship into consideration. The risk quantification has been developed using a questionnaire and incorporated into the new model. A simulation was carried out for the Osaka bay area in order to verify the usefulness of the proposed model. A new approach was employed to monitor the level of navigation safety along a ship route. The entire ship route is divided into small sections as a gridded matrix. The level of navigation safety can be quantified by means of a safety index on the basis of the ship’s navigation data within a specified distance range. The results show that the comparison between risks identified for different sections across the entire ship route is easy, which helps determine the navigational safety zone quickly. This model is expected to be able to serve as a new tool for managing safety throughout an entire ship route area in real-time in order to support the port safety authority or vessel traffic service center

    A New Risk Evaluation Model for Safety Management on an Entire Ship Route

    No full text
    In this paper, we introduce a new risk evaluation model for evaluating the navigation safety zone for an entire ship route. This model considers a new algorithm to determine the navigational safety zone in real-time, and also takes the navigation officers’ perception while navigating a ship into consideration. The risk quantification has been developed using a questionnaire and incorporated into the new model. A simulation was carried out for the Osaka bay area in order to verify the usefulness of the proposed model. A new approach was employed to monitor the level of navigation safety along a ship route. The entire ship route is divided into small sections as a gridded matrix. The level of navigation safety can be quantified by means of a safety index on the basis of the ship’s navigation data within a specified distance range. The results show that the comparison between risks identified for different sections across the entire ship route is easy, which helps determine the navigational safety zone quickly. This model is expected to be able to serve as a new tool for managing safety throughout an entire ship route area in real-time in order to support the port safety authority or vessel traffic service center

    Efficacy and Feasibility of Salvage Re-Irradiation with CyberKnife for In-Field Neck Lymph Node Recurrence: A Retrospective Study

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    Neck lymph node (LN) recurrence in the irradiated field represents an important aspect of treatment failure after primary radiotherapy owing to the lack of a standard treatment. The aim of this study is to investigate the efficacy and safety of CyberKnife treatment for neck LN recurrence after radiotherapy. Between 2008 and 2016, 55 neck LN recurrences after radiotherapy in 16 patients were treated with CyberKnife. The median follow-up period was 17 months (range, 2–53 months). The median previous radiotherapy dose was 68 Gy (range, 50–70 Gy). The median marginal dose as equivalent dose delivered in 2-Gy fractions (α/β = 10) was 50 Gy (range, 40–58 Gy). The one-year local control (LC) and overall survival rates were 81% and 71%, respectively. The one-year LC was higher with a target volume ≤1.0 cm3 than that with a target volume >1.0 cm3 (p = 0.006). Fatal bleeding was observed in one patient who had large (91 cm3) and widespread tumor with invasion to the carotid artery before CyberKnife treatment. CyberKnife treatment for neck LN recurrence is safe and feasible in most cases. Indication for the treatment should be carefully considered for large and widespread tumors

    Congenital amegakaryocytic thrombocytopenia iPS cells exhibit defective MPL-mediated signaling.

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    Congenital amegakaryocytic thrombocytopenia (CAMT) is caused by the loss of thrombopoietin receptor-mediated (MPL-mediated) signaling, which causes severe pancytopenia leading to bone marrow failure with onset of thrombocytopenia and anemia prior to leukopenia. Because Mpl-/- mice do not exhibit the human disease phenotype, we used an in vitro disease tracing system with induced pluripotent stem cells (iPSCs) derived from a CAMT patient (CAMT iPSCs) and normal iPSCs to investigate the role of MPL signaling in hematopoiesis. We found that MPL signaling is essential for maintenance of the CD34+ multipotent hematopoietic progenitor (MPP) population and development of the CD41+GPA+ megakaryocyte-erythrocyte progenitor (MEP) population, and its role in the fate decision leading differentiation toward megakaryopoiesis or erythropoiesis differs considerably between normal and CAMT cells. Surprisingly, complimentary transduction of MPL into normal or CAMT iPSCs using a retroviral vector showed that MPL overexpression promoted erythropoiesis in normal CD34+ hematopoietic progenitor cells (HPCs), but impaired erythropoiesis and increased aberrant megakaryocyte production in CAMT iPSC-derived CD34+ HPCs, reflecting a difference in the expression of the transcription factor FLI1. These results demonstrate that impaired transcriptional regulation of the MPL signaling that normally governs megakaryopoiesis and erythropoiesis underlies CAMT

    Persistent Impairment of Endothelial Vasomotor Function Has a Negative Impact on Outcome in Patients With Coronary Artery Disease

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    ObjectivesWe assessed the hypothesis that changes in endothelial vasomotor function in response to optimized therapy for atherosclerotic coronary artery disease predict future cardiovascular events.BackgroundAlthough endothelial vasomotor dysfunction is a predictor of cardiovascular events, it remains unclear whether reversibility of endothelial dysfunction in response to risk factor reduction provides prognostic information.MethodsThis study included 251 patients with newly diagnosed coronary artery disease and an impaired flow-mediated dilation (FMD) of the brachial artery (FMD <5.5%). Measurement of FMD was repeated after 6 months for individualized and optimized therapy to reduce risk factors according to American College of Cardiology/American Heart Association guidelines. Patients were followed up for 36 months or until 1 of the following events occurred: cardiac death, nonfatal myocardial infarction, recurrent and refractory angina pectoris requiring coronary revascularization, or ischemic stroke.ResultsFMD was persistently impaired (<5.5%) in 104 (41%) patients after 6 months of optimized therapy, whereas it improved (FMD ≥5.5%) in the remaining 147 (59%) patients. During 36 months of follow-up, events occurred in 27 (26%) patients with persistently impaired FMD and in 15 (10%) patients with improved FMD (p < 0.01 by chi-square test). Multivariate Cox hazards analysis showed that persistent impairment of FMD was an independent predictor of events (hazard ratio: 2.9, 95% confidence interval: 1.5 to 6.2, p < 0.01). Baseline FMD before the optimized therapy to reduce risk factor had no significant prognostic information.ConclusionsPersistent impairment of endothelial vasomotor function despite optimized therapy to reduce risk factors has an adverse impact on outcome in coronary artery disease patients
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