108 research outputs found

    Effect of Neutron Irradiation on the Microstructures and Tensile Properties of Different Carbon Fibers

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    Since carbon fiber reinforced carbon composite (C/C composite) materials have high thermal conductivity and good mechanical properties, they have been used as the plasma facing components in fusion facilities. As the plasma facing components are subjected to neutron irradiation in the fusion reactors, it is necessary to use irradiation damage resistant C/C composite materials as plasma facing components. Properties of C/C composite materials after neutron irradiation are generally influenced by irradiation behavior of carbon fiber and carbon matrix. In particular, the effect of irradiation on carbon fiber is important, because it is less crystalline than carbon matrix. The purpose of this study is to evaluate neutron irradiation effects on the microstructures and tensile properties of nine kinds of carbon fibers and to find out the necessary knowledge to identify the radiation resistant carbon fiber

    Simulation approach for the evaluation of tracking accuracy in radiotherapy: A preliminary study

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    Real-time tumor tracking in external radiotherapy can be achieved by diagnostic (kV) X-ray imaging with a dynamic flat-panel detector (FPD). It is important to keep the patient dose as low as possible while maintaining tracking accuracy. A simulation approach would be helpful to optimize the imaging conditions. This study was performed to develop a computer simulation platform based on a noise property of the imaging system for the evaluation of tracking accuracy at any noise level. Flat-field images were obtained using a direct-type dynamic FPD, and noise power spectrum (NPS) analysis was performed. The relationship between incident quantum number and pixel value was addressed, and a conversion function was created. The pixel values were converted into a map of quantum number using the conversion function, and the map was then input into the random number generator to simulate image noise. Simulation images were provided at different noise levels by changing the incident quantum numbers. Subsequently, an implanted marker was tracked automatically and the maximum tracking errors were calculated at different noise levels. The results indicated that the maximum tracking error increased with decreasing incident quantum number in flat-field images with an implanted marker. In addition, the range of errors increased with decreasing incident quantum number. The present method could be used to determine the relationship between image noise and tracking accuracy. The results indicated that the simulation approach would aid in determining exposure dose conditions according to the necessary tracking accuracy. © The Author 2012. Published by Oxford University Press on behalf of The Japan Radiation Research Society and Japanese Society for Therapeutic Radiology and Oncology

    Effects of image lag on real-time target tracking in radiotherapy

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    There is a concern that image lag may reduce accuracy of real-time target tracking in radiotherapy. This study was performed to investigate influence of image lag on the accuracy of target tracking in radiotherapy. Fluoroscopic image: were obtained using a direct type of dynamic flat-panel detector (FPD) system under conditions of target tracking during radiotherapy. The images continued to be read out after X-irradiations and cutoff, and image lag properties in the system were then determined. Subsequently, a tungsten materials plate with a precision edge was mounted on to a motor control device, which provided a constant velocity. The plate was moved into the center of the detector at movement rate of 1 and 20 mm/s, covering lung tumor movement of normal breathing, and MTF and profile curves were measured on the edges covering and uncovering the detector. A lung tumor with blurred edge due to image lag was simulated using the results and then superimposed on breathing chest radiographs of a patient. The moving target with and without image lag was traced using a template-matching technique. In the results, the target could be traced within a margin for error ii external radiotherapy. The results indicated that there was no effect of image lag on target tracking in usual breathing speed in a radiotherapy situation. Further studies are required to investigate influence by the other factors, such a: exposure dose, target size and shape, imaging rate, and thickness of a patient\u27s body. © 2010 SPIE

    Induction of LYVE-1/stabilin-2-positive liver sinusoidal endothelial-like cells from embryoid bodies by modulation of adrenomedullin-RAMP2 signaling

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    Embryonic stem cells (ESCs) are a useful source for various cell lineages. So far, however, progress toward reconstitution of mature liver morphology and function has been limited. We have shown that knockout mice deficient in adrenomedullin (AM), a multifunctional endogenous peptide, or its receptor-activity modifying protein (RAMP2) die in utero due to poor vascular development and hemorrhage within the liver. In this study, using embryoid bodies (EBs)-culture system, we successfully induced liver sinusoidal endothelial-like cells by modulation of AM-RAMP2. In an EB differentiation system, we found that co-administration of AM and SB431542, an inhibitor of transforming growth factor beta (TGF beta) receptor type 1, markedly enhanced differentiation of lymphatic vessel endothelial hyaluronan receptor-1 (LYVE-1)/stabilin-2-positive endothelial cells. These cells showed robust endocytosis of acetylated low-density lipoprotein (Ac-LDL) and upregulated expression of liver sinusoidal endothelial cells (LSECs)-specific markers, including factor 8 (F8), Fc-gamma receptor 2b (Fcgr2b), and mannose receptor C type 1 (Mrc1), and also possessed fenestrae-like structure, a key morphological feature of LSECs. In RAMP2-null liver, by contrast, LYVE-1 was downregulated in LSECs, and the sinusoidal structure was disrupted. Our findings highlight the importance of AM-RAMP2 signaling for development of LSECs. (C) 2011 Elsevier Inc. All rights reserved.ArticlePEPTIDES. 32(9):1855-1865 (2011)journal articl

    Implementasi Permendagri Nomor 15 Tahun 2008 Tentang Pengarusutamaan Gender pada Jenjang Pendidikan Dasar di Kota Malang

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    Windra Rizkiyana1 & Wahyu Widodo21 Mahasiswa & 2Staf Pengajar Program Pasca Sarjana, Universitas Muhammadiyah MalangAlamat Korespondensi : Jl. Bandung No.1 MalangEmail: [email protected] education, still found a gender gap regarding both aspects of the expansion of educationalaccess and equity, quality and relevance of education and management. The purpose of this studywere: (1) describe the substance Permendagri No. 15 of 2008 on Gender Mainstreaming; (2) describethe implementation of Permendagri No. 15 of 2008 on Gender Mainstreaming in Elementary Educationin Malang; (3) Analyze the obstacles encountered in implementation Permendagri No. 15 of 2008 onGender Mainstreaming in Elementary Education in Malang. This type of research is a descriptiveanalysis, using a qualitative approach that is supported by a quantitative approach. And the techniquesof data acolllection through by interviews and the documents. Study sites are in Malang EducationDepartment. Analysis of the data used is descriptive analysis of qualitative and quantitative theorysupported by Gender Analysis Pathway (GAP), Content Analysis and Root Analysis. Implementationof Permendagri No 15 of 2008 about gender mainstreaming in basic education levels in Malang hasnot been optimal. These proved by the remains of gender inequality or gap that occurs in all threeaspects, that access and educational equity, quality and relevance of education, as well as accountabilityand governance. Constraints encountered in implementation Permendagri No. 15 of 2008 on gendermainstreaming in elementary education in Malang include: (a) Outreach activities that are specificallyabout the PUG in primary education has not been done; (b) The budget is not specifically formainstreaming activities; (c) newly formed working group PUG.Key word: Permendagri No. 15 of 2008, gender mainstreaming, basic educatio

    Diagnostic Validity of DNMT-1 and 3b Immunoreactivity in Non-neoplastic Epithelium of UC Patients with and Without Neoplasia

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    It is important to improve the efficacy of surveillance in UC patients with neoplasia.In the present study, we assessed the cut-off value of expression of DNMT-1 and DNMT-3b expression in the non-neoplastic rectal epithelium of patients with long-standing and extensive UC. Sixty patients with long-standing and extensive UC participated in this study( 30 with colorectal neoplasia and 30 without). Immunohistochemical analysis was performed to determine the expression of DNMT-1 and 3b in non-neoplasticrectal epithelium of UC patients without neoplasia, and in non-neoplastic rectal epithelium of UC patients with neoplasia. The level of immunoreactive DNMT-1 and DNMT-3b expression was determined as the percentage of positive cells relative to the total number of cells counted under high power magnification.DNMT-1 and 3b expression in non-neoplastic rectal epithelium of UC patients with neoplasia (0.57, range0.53-0.63)(0.32, range 0.18-0.67) was higher than in the non-neoplastic epithelium of UC patients without neoplasia (0.41, range 0.25-0.54, P=.001)(0.0, range 0.0-0.13, P<.001). ROC curve analysis confirmed0.53 and 0.07 as the best DNMT-1 and DNMT-3b cut-off values for identifying individuals at increased risk of neoplasia( area under the curve=0.798 and 0.842, respectively). The cut-off value for DNMT-1 andDNMT-3b expression in non-neoplastic rectal epithelium is therefore an efficient predictor for the increased risk of UC-associated neoplasia

    Impact of COVID-19 on cardiovascular testing in the United States versus the rest of the world

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    Objectives: This study sought to quantify and compare the decline in volumes of cardiovascular procedures between the United States and non-US institutions during the early phase of the coronavirus disease-2019 (COVID-19) pandemic. Background: The COVID-19 pandemic has disrupted the care of many non-COVID-19 illnesses. Reductions in diagnostic cardiovascular testing around the world have led to concerns over the implications of reduced testing for cardiovascular disease (CVD) morbidity and mortality. Methods: Data were submitted to the INCAPS-COVID (International Atomic Energy Agency Non-Invasive Cardiology Protocols Study of COVID-19), a multinational registry comprising 909 institutions in 108 countries (including 155 facilities in 40 U.S. states), assessing the impact of the COVID-19 pandemic on volumes of diagnostic cardiovascular procedures. Data were obtained for April 2020 and compared with volumes of baseline procedures from March 2019. We compared laboratory characteristics, practices, and procedure volumes between U.S. and non-U.S. facilities and between U.S. geographic regions and identified factors associated with volume reduction in the United States. Results: Reductions in the volumes of procedures in the United States were similar to those in non-U.S. facilities (68% vs. 63%, respectively; p = 0.237), although U.S. facilities reported greater reductions in invasive coronary angiography (69% vs. 53%, respectively; p < 0.001). Significantly more U.S. facilities reported increased use of telehealth and patient screening measures than non-U.S. facilities, such as temperature checks, symptom screenings, and COVID-19 testing. Reductions in volumes of procedures differed between U.S. regions, with larger declines observed in the Northeast (76%) and Midwest (74%) than in the South (62%) and West (44%). Prevalence of COVID-19, staff redeployments, outpatient centers, and urban centers were associated with greater reductions in volume in U.S. facilities in a multivariable analysis. Conclusions: We observed marked reductions in U.S. cardiovascular testing in the early phase of the pandemic and significant variability between U.S. regions. The association between reductions of volumes and COVID-19 prevalence in the United States highlighted the need for proactive efforts to maintain access to cardiovascular testing in areas most affected by outbreaks of COVID-19 infection
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