417 research outputs found

    Group Key Managements in Wireless Sensor Networks

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    Clinicopathological features of infiltrating lobular carcinomas comparing with infiltrating ductal carcinomas: a case control study

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    BACKGROUND: Infiltrating lobular carcinoma (ILC) is the second most common type of invasive breast cancers and it has been reported to have some unique biologic and epidemiologic characteristics. METHODS: Clinicopathological features of 95 patients with ILC, their relapse free survival (RFS) and overall survival (OS) were retrospectively investigated and compared with those of 3,621 patients with infiltrating ductal carcinoma-not otherwise specified (IDC-NOS) between January 1984 and December 2005. RESULTS: ILC constitutes 2.3% of all invasive breast cancers. There were no difference between the ILC and the IDC-NOS groups regarding age at diagnosis, tumor size, nodal status, and treatment modalities except hormone therapy. The ILC group showed more estrogen receptor expression, less HER-2 expression and higher bilaterality. RFS and OS of the ILC patients were similar to those of the IDC. IDC-NOS metastasized more frequently to the lung and bone, whereas, ILC to the bone and ovary. CONCLUSIONS: The incidence of ILC was relatively low in Korean breast cancer patients. Comparing to IDC-NOS ILC showed some different features such as higher estrogen receptor expression, less HER-2 expression, higher bilaterality and preferred metastatic sites of bone and ovary. Contralateral cancers and bone and ovary evaluation should be considered when monitoring ILC patients

    Performance Analysis of the Linear Induction Motor for the Deep-Underground High-Speed GTX

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    Abstract -In order to develop a deep-underground great train express (GTX) in South Korea, the specifications decision and development of a traction control system (including an inverter and a traction motor), which considers a variety of route conditions, must be advanced. In this study, we examined the running resistance properties of a high-speed traction system based on a variety of tunnel types and vehicle organization methods. Then, we studied the power requirements necessary for the traction motor to maintain balanced speed in the high-speed traction system. From this, we determined the design criteria for the development of a high-speed traction system for use in the deep-underground GTX. Finally, we designed a linear induction motor (LIM) for a propulsion system, and we used the finite element method (FEM) to analyze its performance as it travelled through deep-underground tunnels

    Significance of collateral circulation in managing persistent sciatic artery: Two case reports

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    Persistent sciatic artery (PSA) is a rare congenital anomaly considered an embryologic remnant of the internal iliac artery. Traditionally, the classification systems categorized PSA based on the completeness of PSA and superficial femoral artery (SFA) alongside the origin of PSA. The most common class has been known as type 2a in Pillet–Gauffre classification, meaning complete PSA with incomplete SFA. The mainstay of these patients with limb ischemia has been surgical bypass alongside excision or ligation of PSA aneurysm if present. However, the current PSA classification system does not account for collateral blood flow. Herein, we described two cases of type 2a PSA with distal embolization and explored therapeutic choices for PSA based on collateral presence. The first patient was treated with thromboembolectomy and patch angioplasty, and the second with conservative management. Despite distal embolization in both patients, bypass surgery was avoided, and distal circulation was maintained via collaterals from deep and superficial femoral arteries without increased risk of recurrent embolization. Thus, carefully examining collateral circulation and customized strategy is essential for managing PSA

    A pediatric case of idiopathic Harlequin syndrome

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    Harlequin syndrome, which is a rare disorder caused by dysfunction of the autonomic system, manifests as asymmetric facial flushing and sweating in response to heat, exercise, or emotional factors. The syndrome may be primary (idiopathic) with a benign course, or can occur secondary to structural abnormalities or iatrogenic factors. The precise mechanism underlying idiopathic harlequin syndrome remains unclear. Here, we describe a case of a 6-year-old boy who reported left hemifacial flushing and sweating after exercise. He had an unremarkable birth history and no significant medical history. Complete ophthalmological and neurological examinations were performed, and no other abnormalities were identified. Magnetic resonance imaging was performed to exclude lesions of the cerebrum and cervicothoracic spinal cord, and no abnormalities were noted. His final diagnosis was classic idiopathic harlequin syndrome. Herein, we report the first pediatric case of idiopathic harlequin syndrome in Korea

    In situ electrochemically synthesized Pt-MoO3-x nanostructure catalysts for efficient hydrogen evolution reaction

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    Designing and preparing highly active and stable nanostructured Pt-based catalysts with ultralow Pt loading are still challenging for electrochemical applications such as water electrolysis and fuel cells. Here we report for the first time an in situ electrochemical process to synthesize Pt-MoO3-x nanoflakes (NFs) overgrown on commercial bulk MoS2 by employing a facile and simple electrochemical method without using any expensive precious metal salts. The overgrowth of Pt-MoO3-x NFs on the bulk MoS2 surface is conducted by applying electrical energy to the bulkMoS(2) and using Pt counter electrode dissolution in an acidic solution. In spite of their 10 times lower Pt loadings compared to commercial Pt black (Alfa Aesar), the synthesized Pt-MoO3-x NFs demonstrate excellent catalytic performance with a Ptmass activity of 2.83 A/mg(Pt) at the overpotential of 100 mV for electrochemical hydrogen evolution reaction (HER), an approximately 4 times higher value than the value of 0.76 A/mg(Pt) at the overpotential of 100 mVfor commercial Pt black. We hypothesize that the outstanding HER characteristics of Pt-MoO3-x NFs are related to the existence and increase of Pt-MoO3 interfacial sites and oxygen vacancy sites such as Mo5+ in the Pt-MoO3-x NF structures. In addition, our density functional theory (DFT) calculations demonstrate that Pt and O sites at Pt and MoO3 interfaces and O sites at defective MoO3-x in the Pt-MoO3-x NFs contribute to accelerate the HER. (C) 2019 Elsevier Inc. All rights reserved

    The cascade of care for latent tuberculosis infection in congregate settings:a national cohort 1 analysis, Korea, 2017-18

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    BACKGROUND: In 2017, Korea implemented a nationwide project to screen and treat latent tuberculosis infection (LTBI) in high-risk for transmission public congregate settings. We aimed to assess programme success using a cascade of care framework. MATERIALS AND METHODS: We undertook a cohort study of people from three congregate settings screened between March 2017 and December 2018: (1) first-grade high school students, (2) employees of educational institutions, (3) employees of social welfare facilities. We report percentages of participants with LTBI completing each step in the cascade of care model. Poisson regression models were used to determine factors associated with not visiting clinics, not initiating treatment, and not completing treatment. RESULTS: Among the 96,439 participants who had a positive interferon-gamma release assay result, the percentage visiting clinics for further assessment, to initiate treatment, and who then completed treatment were 50.7, 34.7, and 28.9%, respectively. Compared to those aged 20-34 years, individuals aged < 20 years and aged ≥ 65 years were less likely to visit clinics, though more likely to complete treatment once initiated. Using public health centres rather than private hospitals was associated with people "not initiating treatment" (adjusted risk ratio [aRR], 3.72; 95% confidence interval [CI], 3.95-3.86). Nine-month isoniazid monotherapy therapy was associated with "not completing treatment," compared to 3-month isoniazid and rifampin therapy (aRR, 1.28; 95% CI, 1.16-1.41). CONCLUSION: Among participants with LTBI from three congregate settings, less than one third completed treatment. Age, treatment centre, and initial regimen were important determinants of losses to care through the cascade
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