73 research outputs found

    Design report of the KISS-II facility for exploring the origin of uranium

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    One of the critical longstanding issues in nuclear physics is the origin of the heavy elements such as platinum and uranium. The r-process hypothesis is generally supported as the process through which heavy elements are formed via explosive rapid neutron capture. Many of the nuclei involved in heavy-element synthesis are unidentified, short-lived, neutron-rich nuclei, and experimental data on their masses, half-lives, excited states, decay modes, and reaction rates with neutron etc., are incredibly scarce. The ultimate goal is to understand the origin of uranium. The nuclei along the pathway to uranium in the r-process are in "Terra Incognita". In principle, as many of these nuclides have more neutrons than 238U, this region is inaccessible via the in-flight fragmentation reactions and in-flight fission reactions used at the present major facilities worldwide. Therefore, the multi-nucleon transfer (MNT) reaction, which has been studied at the KEK Isotope Separation System (KISS), is attracting attention. However, in contrast to in-flight fission and fragmentation, the nuclei produced by the MNT reaction have characteristic kinematics with broad angular distribution and relatively low energies which makes them non-amenable to in-flight separation techniques. KISS-II would be the first facility to effectively connect production, separation, and analysis of nuclides along the r-process path leading to uranium. This will be accomplished by the use of a large solenoid to collect MNT products while rejecting the intense primary beam, a large helium gas catcher to thermalize the MNT products, and an MRTOF mass spectrograph to perform mass analysis and isobaric purification of subsequent spectroscopic studies. The facility will finally allow us to explore the neutron-rich nuclides in this Terra Incognita.Comment: Editors: Yutaka Watanabe and Yoshikazu Hirayam

    Development of Gas Multiplier Counters (GMCs) Onboard the 6U CubeSat X-Ray Observatory NinjaSat

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    We report the development of Gas Multiplier Counters (GMCs) onboard the 6U CubeSat X-ray observatory NinjaSat, scheduled to be launched in October 2023. GMC is a 1U-size non-imaging gas X-ray detector sensitive to 2–50 keV X-rays, and two identical GMCs are mounted on NinjaSat. GMC consists of a gas cell filled with a xenon/argon/dimethyl ether (75%/24%/1%) gas mixture with a pressure of 1.2 atm at 0◦C, a high voltage supply and analog signal processing board, a digital signal processing board, an X-ray collimator of a 2.1◦ field of view, and an iron-55 calibration source. The most significant feature of the GMC is its large effective area of 32 cm2 at 6 keV, which is more than two orders of magnitude larger than the X-ray detectors onboard previously launched CubeSats. We have achieved this at a low cost and in a short development time by employing a gas detector that can easily increase its effective area and using a space-proven gas electron multiplier. GMC was characterized with X-rays from an X-ray generator in a laboratory and monochromatic X-rays on the BL-14A beamline at the KEK synchrotron radiation facility. In this paper, we present the design of GMC and the preliminary results of the detector calibration

    A Young Adult Patient with Nonalcoholic Steatohepatitis Developed Severe Gastroesophageal Varices Associated with Severe Obesity and Diabetes Mellitus

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    Obesity is a major contributor to insulin resistance and nonalcoholic fatty liver disease, which is the most common cause of chronic liver diseases. Nonalcoholic steatohepatitis (NASH) can progress to liver cirrhosis and end-stage liver diseases. Some cases already show severe liver fibrosis at the time of diagnosis. We present the case of a 44-year-old male with overt obesity who was admitted with hematemesis due to the rupture of gastric varices. We diagnosed him with NASH with severe liver fibrosis. This case shows that we should be concerned about the progression of liver fibrosis due to NASH associated with severe obesity even in young patients

    NinjaSat: 6U CubeSat Observatory for Bright X-Ray Sources

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    NinjaSat is a 6U CubeSat observatory designed for long-term monitoring of bright X-ray sources, such as binary systems between normal stars and black holes or neutron stars. NinjaSat is the first Japanese CubeSat dedicated to astronomical observation, and it is also a mission to demonstrate that even a small satellite, which can be developed quickly and inexpensively, unlike large satellites, can perform excellent scientific observations. NinjaSat realizes the world’s highest X-ray sensitivity in CubeSat missions by using gas X-ray detectors filling the entire space allocated for science payloads. The fabrication of the flight model payloads began in 2021, and testing at the payload component level was completed in August 2022; as of April 2023, the payloads were integrated into the Nano Avionics 6U bus (M6P) in Lithuania. After four months of testing, the payload will be stored in the Exolaunch deployer in August and launched by the SpaceX Transporter-9 mission in October 2023. This paper will describe the scientific objectives, satellite structure, payloads, and operations of NinjaSat

    Tissue Intrinsic Fluorescence Spectra-Based Digital Pathology of Liver Fibrosis by Marker-Controlled Segmentation

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    Tissue intrinsic emission fluorescence provides useful diagnostic information for various diseases. Because of its unique feature of spectral profiles depending on tissue types, spectroscopic imaging is a promising tool for accurate evaluation of endogenous fluorophores. However, due to difficulties in discriminating those sources, quantitative analysis remains challenging. In this study, we quantitatively investigated spectral-spatial features of multi-photon excitation fluorescence in normal and diseased livers. For morphometrics of multi-photon excitation spectra, we examined a marker-controlled segmentation approach and its application to liver fibrosis assessment by employing a mouse model of carbon tetrachloride (CCl4)-induced liver fibrosis. We formulated a procedure of internal marker selection where markers were chosen to reflect typical biochemical species in the liver, followed by image segmentation and local morphological feature extraction. Image segmentation enabled us to apply mathematical morphology analysis, and the local feature was applied to the automated classification test based on a machine learning framework, both demonstrating highly accurate classifications. Through the analyses, we showed that spectral imaging of native fluorescence from liver tissues have the capability of differentiating not only between normal and diseased, but also between progressive disease states. The proposed approach provides the basics of spectroscopy-based digital histopathology of chronic liver diseases, and can be applied to a range of diseases associated with autofluorescence alterations

    Development of Radiation Belt Monitors for the 6U CubeSat X-Ray Observatory NinjaSat

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    NinjaSat is a 6U CubeSat-sized X-ray observatory to be launched into the low Earth orbit at an altitude of 550 km, and is scheduled for launch this October. NinjaSat is equipped with two 1U-sized gas X-ray detectors (GMC) and is expected to operate mainly for astronomical observations of bright X-ray objects in the sky, such as neutron stars and black holes. Since high voltages are applied to the gas cells of GMC, two radiation belt monitors (RBM) will also be installed to protect GMC from electrical discharges potentially caused by excessively high rate of charged particles. NinjaSat RBM will play a fail-safe function in the voltage suppression operation of GMC in the auroral zone and South Atlantic Anomaly, and also protect GMC from charged particles such as protons and electrons that arrive unexpectedly due to solar flares or other low-Earth orbit radiation events. RBM uses a 9 mm x 9 mm Si-PIN photodiode as a charged particle sensor. By taking advantage of the difference in sensor response to protons and electrons, the sensor is designed to simultaneously count charged particle rates at multiple energy thresholds so that GMC protection function will operate even if either the proton or electron rate increases. RBM can count up to about 10 kcps with almost no loss of counts, and proton beam tests have confirmed that the response performance is sufficient to protect GMC against excessively high charged particle rates above 10 Mcps without choking the circuitry. The flight models of the RBM have passed the thermal vacuum and vibration tests last year. The developed RBM occupies only about 6% of the 1U CubeSat size in volume and weighs only 70g. In addition, since the RBM uses inexpensive, commercially available sensors, it could be installed on small satellites other than NinjaSat with relatively small development resources

    Green odor attenuates a cold pressor test-induced cardiovascular response in healthy adults

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    <p>Abstract</p> <p>Background</p> <p>Green odor, a mixture of equal amounts of 2<it>E</it>-hexenal (leaf aldehyde) and 3Z-hexenol (leaf alcohol) has been demonstrated to have an anti-stress effect in rats. This study investigated whether or not green odor also has an anti-stress effect in humans.</p> <p>Methods</p> <p>Changes in blood pressure, heart rate, and the skin temperature of a fingertip were observed after presenting green odor at a concentration of 0.03% or vehicle via inhalation through the nose for 10 min to eight healthy normotensive adults. We also assessed the pleasantness of green odor and its effect on mood states via assessment with the Profile of Mood States (POMS) questionnaire. Cardiovascular response to green odor and the vehicle were compared among 11 additional healthy adults by use of the cold pressor test.</p> <p>Results</p> <p>Of 19 subjects, 15 (79%) reported that the green odor was pleasant. Green odor had no effect on blood pressure, heart rate, skin temperature, or POMS score under non-stressful conditions. In the second experiment, green odor attenuated cold pressor test-induced increases in systolic and diastolic blood pressure and facilitated the recovery of skin temperature.</p> <p>Conclusion</p> <p>These findings suggest that green odor has an anti-stress effect in healthy humans.</p

    Concept-based teaching and learning for reconstructing the meaning of peace: a practice of integrated study in Hiroshima Global Academy

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    The aim of this study is to design the peace education unit, which support the students to achieve the two goals: (1) to reconstruct their own notions of peace, and (2) to acquire interdisciplinary concepts and apply them to find and describe the (non-)peaceful situations in our usual life. Therefore, we developed and implemented a concept based inquiry unit (18 class hours) at Hiroshima Global Academy (HiGA) middle school by contextualize the previous unit plan into the integrated learning program on “Global Justice.” As a result, we could choose the six concepts explaining a nonviolent but threatening the peaceful governance, human relation, and agency, demonstrate the social examples to apply them, and set a controversy defining the criteria of peace. The first outcome of this study is that we show the curricular-instructional gatekeeping adjusting to the school context of HiGA. The second is to find the relations between the students' learning of peace concepts and the reconstruction of peace notion

    <リサーチ・ペーパー>茨城県大洗町におけるツーリズム形態の変容に伴う観光空間の再編

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    本研究は茨城県大洗町におけるコンテンツ・ツーリズムの展開に注目し,ツーリズム形態の転換に伴う観光空間への影響,及びその変容の解明を目的とした。大洗町は観光施設を数多く有する県内でも有数の海浜観光地であり,2012年以降はアニメ「ガールズ&パンツァー」の舞台として新たな観光現象が生じている地域である。大洗町においては,当初は店舗・組織におけるアニメファンへの対応はまちまちであったが,多くの訪問客が訪れるにつれて,商工会の主導により積極的にコンテンツを地域の資源として取り入れ,多くのアニメファンを来訪者として呼び込むことに成功した。宿泊業においては,アニメ放映以前までは夏季の家族連れや団体客が宿泊者の中心であったが,放映以降は夏季以外の1人客の割合が大きく増加するなど変化が生じた。コンテンツ・ツーリズムの導入によるホスト・ゲスト間の関係性の変化は新たな観光者を呼ぶ契機となったが明らかとなった。This research focuses on the development of content tourism in Oarai town, Ibaraki Prefecture, Japan, and aims to clarify the influence on the tourism space brought about by changes in the essential character of the tourism. The subject area is one of the premier destinations in the prefecture, which has many facilities. After 2012 , a new trend in tourism appear to have been motivated by the Japanese animation Girls & Panzer. As the number of tourists inspired by the show increased, the Chamber of Commerce, shops, and commercial facilities actively used them as regional resources. As a result, they succeeded in attracting many fans as a tourist to shopping street. Before the animation aired, the accommodation industry served mostly families and group guests in the summer season. After the show aired, there were changes, such as a large increase in the proportion of individual customers visiting and in seasons other than summer, and changes in the relationship between hosts and guests. The introduction of content tourism also led to a greater number of tourists there overall

    リピーターの観光行動からみたアニメツーリズムの持続性 : 茨城県大洗町「ガールズ&パンツァー」を事例として

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    本研究にあたり,2016~17年度科学研究費(挑戦的萌芽研究)「聖地共創時代におけるオタクの癒し空間に関する応用地理学的研究」(研究代表者:松井圭介)の一部を利用した
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