233 research outputs found
Microstructure of Oxide Insulator Coating before and after Thermal Cycling Test
Erbium oxide (Er2O3) was shown to be a high potential candidate for tritium permeation barrier and electrical insulator coating for advanced breeding blanket systems such as liquid Li, Li-Pb or molten-salt blankets. Recently, we succeeded to form Er2O3 coating layer on large interior surface area of metal pipe using Metal Organic Chemical Vapor Deposition (MOCVD) process. In this paper, we investigated the microstructure of Er2O3 coating layer on stainless steel 316 (SUS 316) plate before and after heat treatments with hydrogen or argon gases. From the results of TEM observations, we confirmed that Er2O3 coating layer with 700 nm thickness was formed on the SUS 316 plate and this layer was identified to poly-crystal phase because the diffraction fleck which was arranged like a ring was observed in the selected electron diffraction pattern. No macroscopic defects such as crack and peeling in Er2O3 coating layer were observed before and after thermal cycling test. The change of microstructure of the Er2O3 coating layer on before and after heat cycling test was reported
Microstructure of Erbium Oxide Thin Film on SUS316 Substrate with YāOā or CeOā Buffer Layers Formed by MOCVD Method
Er2O3 has been known the best candidate material for insulating coating for liquid metal breeding blanket system. The formation of Er2O3 layer by MOCVD method can be succeeded on SUS316 substrate with CeO2 and Y2O3 buffer layers (100 nm and 500 nm) fabricated by RF sputtering, and their microstructures have been confirmed by SEM, TEM and STEM. The surface morphology of their layers was smaller granular structure than the previous study without buffer layer. According to cross sectional TEM (X-TEM) observation, Er2O3, CeO2/Y2O3 buffer, unknown layers and SUS substrate can be confirmed. CeO2 buffer layer has a granular structure, while Y2O3 has a columnar structure. Er2O3 layer formed on each buffer layer had finer structure without buffer layer. It has been also detected that each element does not exist so much in each layer by diffusion during fabrication according to STEM-EDS and HAADF imaging
Design Window Analysis for the Helical DEMO Reactor FFHR-d1
Conceptual design activity for the LHD-type helical DEMO reactor FFHR-d1 has been conducted at the National Institute for Fusion Science under the Fusion Engineering Research Project since FY2010. In the first step of the conceptual design process, design window analysis was conducted using the system design code HELIOSCOPE by the āDesign Integration Task Groupā. On the basis of a parametric scan with the core plasma design based on the DPE (Direct Profile Extrapolation) method, a design point having a major radius of 15.6 m and averaged magnetic field strength at the helical coil winding center of 4.7 T was selected as a candidate. The validity of the design was confirmed through the analysis by the related task groups (in-vessel component, blanket, and superconducting magnet)
Seismic Analysis of Magnet Systems in Helical Fusion Reactors Designed With Topology Optimization
Superconducting magnets in fusion reactors are subjected to a huge electromagnetic force of >100 MN/m. The magnets have to be sustained with a strong-body structure to avoid high stress and deformation. The total weight of the magnet system in the fusion reactor is estimated to be more than 20,000 tons. We applied topology optimization technique to the magnet support structure to reduce the weight of fusion reactors. Compared with the conventional design, we achieved a weight reduction of >25%. Static and seismic analyses were carried out to validate the soundness of the topology-optimized design. Consequently, the stress against the electromagnetic force in the structure was within the permissible range. It was discovered that using seismic isolation structure can adequately prevent the damage to the magnet system even when directly subjected to a massive earthquake
Human T-cell leukemia virus type I infects human lung epithelial cells and induces gene expression of cytokines, chemokines and cell adhesion molecules
<p>Abstract</p> <p>Background</p> <p>Human T-cell leukemia virus type I (HTLV-I) is associated with pulmonary diseases, characterized by bronchoalveolar lymphocytosis, which correlates with HTLV-I proviral DNA in carriers. HTLV-I Tax seems to be involved in the development of such pulmonary diseases through the local production of inflammatory cytokines and chemokines in T cells. However, little is known about induction of these genes by HTLV-I infection in lung epithelial cells.</p> <p>Results</p> <p>We tested infection of lung epithelial cells by HTLV-I by coculture studies in which A549 alveolar and NCI-H292 tracheal epithelial cell lines were cocultured with MT-2, an HTLV-I-infected T-cell line. Changes in the expression of several cellular genes were assessed by reverse transcription-polymerase chain reaction, enzyme-linked immunosorbent assay and flow cytometry. Coculture with MT-2 cells resulted in infection of lung epithelial cells as confirmed by detection of proviral DNA, HTLV-I Tax expression and HTLV-I p19 in the latter cells. Infection was associated with induction of mRNA expression of various cytokines, chemokines and cell adhesion molecule. NF-ĪŗB and AP-1 were also activated in HTLV-I-infected lung epithelial cells. <it>In vivo </it>studies showed Tax protein in lung epithelial cells of mice bearing Tax and patients with HTLV-I-related pulmonary diseases.</p> <p>Conclusion</p> <p>Our results suggest that HTLV-I infects lung epithelial cells, with subsequent production of cytokines, chemokines and cell adhesion molecules through induction of NF-ĪŗB and AP-1. These changes can contribute to the clinical features of HTLV-I-related pulmonary diseases.</p
Mechanical Design Concept of Superconducting Magnet System for Helical Fusion Reactor
The conceptual design of a helical fusion reactor was studied at the National Institute for Fusion Science in collaboration with other universities. Two types of the force free helical reactor (FFHR) are FFHR-d1 and FFHR-c1. FFHR-d1 is a self-ignition demonstration reactor that operates with a major radius of 15.6 m at a magnetic field intensity of 4.7 T. FFHR-c1 is a compact subignition reactor that aims to realize steady electrical self-sufficiency. Compared to FFHR-d1, FFHR-c1 has a magnetic field intensity of 7.3 T and a geometrical scale of 0.7. The location of the superconducting coils in both types of FFHR is based on that of the Large Helical Device (LHD). LHD has a major radius of 3.9 m. According to the design of LHD, the deformation must be within the required value to compensate for the accuracy of the magnetic field. According to this concept, the magnet support structure of LHD was fabricated using thick Type 316 stainless steel to impart sufficient rigidity. Thus, the stress of the magnet system of LHD is sufficiently below the permissible stress. In the case of FFHR, from the viewpoint of the reactor, a large access port is required for the maintenance of the in-vessel components. The mechanical design of the support structure is conceptualized by considering the basic thickness of the material and residual aperture space by referencing the mechanical analysis results. Details of the design concepts of LHD and FFHR-d1/FFHR-c1 as well as the results of mechanical analyses are introduced in this paper
Nationwide surveillance of AIDS-defining illnesses among HIV patients in Japan from 1995 to 2017
Objectives: The accurate prevalence of acquired immunodeficiency syndrome (AIDS)-defining illnesses (ADIs) in human immunodeficiency virus (HIV)-infected patients has not been well investigated. Hence, a longitudinal nationwide surveillance study analyzing the current status and national trend of opportunistic complications in HIV-infected patients in Japan is warranted.Methods: A nationwide surveillance of opportunistic complications in HIV-infected patients from 1995 to 2017 in Japan was conducted. An annual questionnaire was sent to 383 HIV/AIDS referral hospitals across Japan to collect information (CD4+ lymphocyte count, time of onset, outcome, and antiretroviral therapy [ART] status) of patients diagnosed with any of 23 ADIs between 1995 and 2017.Results: The response and case capture rates of the questionnaires in 2017 were 53% and 76%, respectively. The number of reported cases of opportunistic complications peaked in 2011 and subsequently declined. Pneumocystis pneumonia (38.7%), cytomegalovirus infection (13.6%), and candidiasis (12.8%) were associated with the cumulative incidence of ADIs between 1995 and 2017. The mortality rate in HIV-infected patients with opportunistic complications substantially decreased to 3.6% in 2017. The mortality rate was significantly higher in HIV patients who received ART within 14 days of diagnosis of complications than in those who received ART 15 days after diagnosis (13.0% vs. 3.2%, p < 0.01).Conclusions: We have demonstrated a 23-year trend of a newly diagnosed AIDS status in Japan with high accuracy. The current data reveal the importance of Pneumocystis pneumonia as a first-onset illness and that early initiation of ART results in poor outcomes in HIV patients in Japan
Early Intensive Nutrition Intervention with Dietary Counseling and Oral Nutrition Supplement Prevents Weight Loss in Patients with Advanced Lung Cancer Receiving Chemotherapy: A Clinical Prospective Study
ćBackgroundć Weight loss in patients with cancer is caused by cancer cachexia and chemotherapy-induced nausea and vomiting (CINV). Recent developments in antiemetic drugs have substantially improved CINV, but nutritional intervention did not improve body weight. This study aimed to investigate the effects of nutrition intervention with appropriate antiemetic treatment in patients with non-small-cell lung cancer during chemotherapy. ćMethodsć Patients received individualized nutrition counseling by a registered dietitian and were provided with oral supplements for 90 days. Body weight and other parameters were measured at baseline and after 90-day intervention. To evaluate this nutrition intervention, patients were also retrospectively set as control, and then body weight change was compared with inverse probability of treatment weights (IPTW) analysis. ćResultsć Ten patients received individualized nutrition counseling and were provided with oral supplements for 90 days. Of them, 7 patients consumed nutritional supplements, and the mean intake was 130 kcal/day. After 90-day intervention, the patients did not show significant weight and BMI loss during the course of cytotoxic chemotherapy. A total of 38 patients were retrospectively enrolled as controls. The number of the patients who gain the body weight after 90 days in the study cohort was significantly larger than that in the retrospective controls with the IPTW analysis (Odds Ratio (OR) = 8.4; 95% Confidence Interval (CI): 1.6-42; P = 0.01). ćConclusionć Early intensive nutrition intervention with appropriate antiemetic treatment prevents weight loss. Nutrition interventions might be also beneficial for quality of life, treatment response and survival
Effect of coil configuration parameters on the mechanical behavior of the superconducting magnet system in the helical fusion reactor FFHR
FFHR-d1A and c1 are the conceptual design of a helical fusion reactor. The positional relationship among superconducting coils, a pair of helical coils with two sets of vertical-field coils, are observed to be similar in both type of FFHR. Such a relation of coil configuration is based on the coil configuration of the Large Helical Device, which has been designed and constructed at the National Institute for Fusion Science. There is increasing demand to achieve an optimized coil configuration to anticipate improvements in plasma-confinement conditions. In this study, the structural design of FFHR based on the fundamental set of parameters of coil configuration is depicted, which satisfies the soundness of the structure. Further, the effects of the coil configuration parameters on the stress distributions are investigated. An effect of radius of curvature on a winding scheme of the helical coil is also discussed
Site-specific isotope labeling of long RNA for structural and mechanistic studies
A site-specific isotope labeling technique of long RNA molecules was established. This technique is comprised of two simple enzymatic reactions, namely a guanosine transfer reaction of group I self-splicing introns and a ligation with T4 DNA ligase. The trans-acting group I self-splicing intron with its external cofactor, āisotopically labeled guanosine 5ā²-monophosphateā (5ā²-GMP), steadily gave a 5ā²-residue-labeled RNA fragment. This key reaction, in combination with a ligation of 5ā²-remainder non-labeled sequence, allowed us to prepare a site-specifically labeled RNA molecule in a high yield, and its production was confirmed with 15N NMR spectroscopy. Such a site-specifically labeled RNA molecule can be used to detect a molecular interaction and to probe chemical features of catalytically/structurally important residues with NMR spectroscopy and possibly Raman spectroscopy and mass spectrometry
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