107 research outputs found

    Image slicer module for Wide Field Optical Spectrograph (WFOS)

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    Wide-Field Optical Spectrograph (WFOS) is an optical multi-object spectrograph and one of the first-light instruments of Thirty Meter Telescope (TMT). The WFOS development team has studied three new instrument concepts. One is a fiber-based spectrograph, and other one is a spectrograph using image slicers (Slicer-WFOS). The last one is the simple multi-slit spectrograph. Japanese WFOS team has conducted conceptual studies on Slicer-WFOS in collaboration with California Institute of Technology. Slicer-WFOS has only one VPH grating for each red and blue arm. The gratings offer R~1,500 for a simple 0.″75-width slit. The image slicer divides an object image into three slices and the higher spectral resolution of R~4,500 can be achieved using the same grating. In this proceeding paper, we report our design studies on the slicer module

    Image slicer module for Wide Field Optical Spectrograph (WFOS)

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    Wide-Field Optical Spectrograph (WFOS) is an optical multi-object spectrograph and one of the first-light instruments of Thirty Meter Telescope (TMT). The WFOS development team has studied three new instrument concepts. One is a fiber-based spectrograph, and other one is a spectrograph using image slicers (Slicer-WFOS). The last one is the simple multi-slit spectrograph. Japanese WFOS team has conducted conceptual studies on Slicer-WFOS in collaboration with California Institute of Technology. Slicer-WFOS has only one VPH grating for each red and blue arm. The gratings offer R~1,500 for a simple 0.″75-width slit. The image slicer divides an object image into three slices and the higher spectral resolution of R~4,500 can be achieved using the same grating. In this proceeding paper, we report our design studies on the slicer module

    Design study of an image slicer module for a multiobject spectrograph

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    We investigate an image slicer module for an optical multiobject spectrograph, wide-field optical spectrograph (WFOS), which is one of the first-light instruments of the Thirty Meter Telescope (TMT). The image slicer divides the target image into three slices, thus providing a one-third narrower slit width. By positioning a suite of such modules at the telescope focal surface, multiobject spectroscopy with high spectral resolution can be achieved. Three optical designs are developed: a two-mirror design, a four-mirror design, and a flat-mirror design. Comparing them, the flat-mirror design is found to be the most preferable for WFOS. From a tolerance analysis, the tolerances of manufacturing and assembling appear challenging but not insurmountable. We describe how the steep field curvature of TMT requires at least nine module variants, tuned to reduce defocus in specific focal surface zones. Finally, we introduce a viable mechanical packaging concept

    Etiler'de Locanda

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    Taha Toros Arşivi, Dosya No: 112-Lokantalarİstanbul Kalkınma Ajansı (TR10/14/YEN/0033) İstanbul Development Agency (TR10/14/YEN/0033

    Analysis of prostate intensity- and volumetric-modulated arc radiation therapy planning quality with PlanIQTM

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    Purpose: The purpose of this study was to assess the quality of treatment planning using the PlanIQTM software and to investigate whether it is possible to improve the quality of treatment planning using the “Feasibility dose-volume histogram (DVH)TM” implemented in the PlanIQTM software. Methods: Using the PlanIQTM software, we retrospectively analyzed the learning curve regarding the quality of the treatment plans for 148 patients of prostate intensity-modulated radiation therapy and volumetric-modulated radiation therapy performed at our institution over the past eight years. We also sought to examine the possibility of improving treatment planning quality by re-planning in 47 patients where the quality of the target dose and the dose limits for organs at risk (OARs) were inadequate. The re-planning treatment plans referred to the Feasibility DVHTM implemented in the PlanIQTM software and modified the treatment planning system based on the target dose and OAR constraints. Results: Analysis of the learning curve of the treatment plans quality using PlanIQTM software retrospectively showed a trend of improvement in the treatment plan quality from year to year. The improvement in the treatment plans quality was more influenced by dose reduction in the OARs than by target coverage. In all cases where re-planning was performed, the improvement in the treatment plan's quality resulted in a better treatment plan than the one adopted for delivery to patients in the clinical plan. Conclusions: The PlanIQTM provided insights into the quality of the treatment plans at our institution and identified problems and areas for improvement in the treatment plans, allowing for the development of appropriate treatment plans for specific patients

    Decreased cholinesterase level combined with renal dysfunction and sympathetic denervation associated with increased cardiac mortality in systolic heart failure

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    AimsCardiac mortality in patients with heart failure (HF) is likely to be aggravated by malnutrition, assessed by serum cholinesterase (ChE) level, as well as by kidney dysfunction or impairment of cardiac sympathetic denervation. Their prognostic interactions, however, have not been determined.MethodsA total of 991 systolic HF patients were enrolled in our HF database following clinical evaluation including evaluation of the nutrition state and assessment of standardized heart-to-mediastinum ratio (sHMR) of iodine-123-labeled meta-iodobenzylguanidine activity. Patients were followed up for an average of 43 months with the primary endpoint of fatal cardiac events (CEs).ResultsThe CE patient group had a lower level of ChE, lower estimated glomerular filtration rate (eGFR) and lower late sHMR than those in the non-CE patient group. A five-parameter model with the addition of serum ChE selected in the multivariate logistic analysis (model 2) significantly increased the AUC predicting risk of cardiac events compared with a four-parameter model without serum ChE (model 1), and net reclassification analysis also suggested that the model with the addition of serum cholinesterase significantly improved cardiac event prediction. Moreover, in overall multivariate Cox hazard analysis, serum ChE, eGFR and late sHMR were identified to be significant prognostic determinants. HF patients with two or all of the prognostic variables of serum ChE < 230 U/L, eGFR < 48.8 ml/min/1.73 m2 and late sHMR < 1.90 had significantly and incrementally increased CE rates compared to those in HF patients with none or only one of the prognostic variables.ConclusionDecreases in cholinesterase level and kidney function further increase cardiac mortality risk in HF patients with impairment of cardiac sympathetic innervation

    Design study of an image slicer module for a multiobject spectrograph

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    We investigate an image slicer module for an optical multiobject spectrograph, wide-field optical spectrograph (WFOS), which is one of the first-light instruments of the Thirty Meter Telescope (TMT). The image slicer divides the target image into three slices, thus providing a one-third narrower slit width. By positioning a suite of such modules at the telescope focal surface, multiobject spectroscopy with high spectral resolution can be achieved. Three optical designs are developed: a two-mirror design, a four-mirror design, and a flat-mirror design. Comparing them, the flat-mirror design is found to be the most preferable for WFOS. From a tolerance analysis, the tolerances of manufacturing and assembling appear challenging but not insurmountable. We describe how the steep field curvature of TMT requires at least nine module variants, tuned to reduce defocus in specific focal surface zones. Finally, we introduce a viable mechanical packaging concept

    Design, Synthesis, and Chemical and Biological Properties of Cyclic ADP-4-Thioribose as a Stable Equivalent of Cyclic ADP-Ribose

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    Here we describe the successful synthesis of cyclic ADP-4-thioribose (cADPtR, 3), designed as a stable mimic of cyclic ADP-ribose (cADPR, 1), a Ca2+-mobilizing second messenger, in which the key N1-β-thioribosyladenosine structure was stereoselectively constructed by condensation between the imidazole nucleoside derivative 8 and the 4-thioribosylamine 7 via equilibrium in 7 between the α-anomer (7α) and the β-anomer (7β) during the reaction course. cADPtR is, unlike cADPR, chemically and biologically stable, while it effectively mobilizes intracellular Ca2+ like cADPR in various biological systems, such as sea urchin homogenate, NG108-15 neuronal cells, and Jurkat T-lymphocytes. Thus, cADPtR is a stable equivalent of cADPR, which can be useful as a biological tool for investigating cADPR-mediated Ca2+-mobilizing pathways

    Education for Disaster Prevention in England : Analysis of Secondary Geography Textbooks

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    The purpose of this study is to clarify the aims, contents and activities of education for disaster prevention on geographical education in England, by analysis of secondary textbooks. Thereby, we want to contribute the improvement of Japanese geographical education. As a result, we clarified the following: 1) when students study a natural disaster in UK, they learn a plurality of cases including domestic and foreign regions, 2) all textbooks contain activities that students can form attitudes and decide what to do for disaster prevention. On the basis of these results, we suggest improvements of education for disaster prevention. The first is to develop a clear understanding of a natural disaster with multi-area including Japan. The second is to place contents and activities for forming a value relevant to awareness of disaster prevention into Japanese geography textbook. The third is to set an activity to learn practical strategies for disaster prevention in the real world
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