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We are developing a new electron beam position monitor (BPM) system for the low-emittance upgrade of SPring-8. The requirements for the BPM system are: (1) a single-pass resolution of 100 µm rms for a 100 pC bunch and an electric center accuracy of 100 µm rms for the initial beam commissioning to achieve the first turn, (2) a closed-orbit distortion (COD) resolution better than 0.1 µm rms for a 100 mA stored beam and a position stability of less than 5 µm for the ultimate stability of a photon beam axis. We have completed prototypes of a precise button electrode and a BPM block to obtain high-intensity signals and sufficient mechanical accuracy while suppressing high-Q trapped modes leading to impedance and heating issues. The development of readout electronics based on the MTCA.4 standard and the evaluation of radiation-hard coaxial cables have also been conducted. The prototype BPM head was installed in the present SPring-8 storage ring for performance verification with an actual electron beam. We confirmed sufficient signal intensity, electric center accuracy, position stability, etc. by the beam test. The new BPM system is almost ready for the SPring-8 upgrade., Proceedings of the 7\textsuperscript{th} Int. Beam Instrumentation Conf., IBIC2018, Shanghai, China

The requirements for a BPM system for the SPring-8 upgrade are long-term stability, sufficient signal intensity and high accuracy*. The design of a button-type electrode for the BPM has been optimized from the perspectives of 1) mechanical structure, 2) rf characteristics, 3) thermal issue. We have adopted the electrode structure without a sleeve enclosing the button to maximize the button diameter for the narrow aperture of the vacuum chamber. The absence of an annular slot around the sleeve in a lodging hole for the electrode eliminates the associated beam impedance. To minimize the beam impedance and the trapped mode heating of the electrode, the rf structure has been optimized by 3D electro-magnetic simulations. To suppress the ohmic loss on the button and center pin thermally isolated from the water cooled BPM block, we have selected molybdenum as a material with high electric and thermal conductivities. The reduction of the heating suppresses thermal deformation of the electrode and the BPM block, and improves thermal stability of the BPM system. The mechanical tolerance of the electrode was defined to fit the error budget for the total BPM offset error of 0.1 mm rms., Proceedings of the 5th Int. Beam Instrumentation Conf., IBIC2016, Barcelona, Spain

We are developing a stable and precise BPM system for the low-emittance upgrade of SPring-8. One of the essential requirements for the BPM is the long term stabilization of the photon beam by regulating the electron beam orbit. Both the single-pass resolution of 100 um rms for an injected beam charge of 100 pC and an accuracy of 100 um rms are also crucial for beam commissioning. Drift sources of the present BPM system have been investigated extensively, such as humidity-dependent drifts coming from the radiation damage of coaxial cables, and the results are fed back to the design of the new BPM system. We have optimized the design of the button BPM electrodes to reconcile reduction of trapped-mode heating and maximization of the signal intensity. Stringent machining tolerance is imposed on a BPM head to align the BPM electric center accurately. A few kinds of the BPM head prototypes were produced and the machining accuracy, RF characteristics etc. were confirmed to be sufficient. We have installed one of the prototypes in the present storage ring to test the performance of the new BPM system under development, and have been obtaining successful results satisfying the requirements., Proceedings of the 8th Int. Particle Accelerator Conf., IPAC2017, Copenhagen, Denmark

The RF system of the SPring-8 storage ring has stably generated an accelerating voltage of 16 MV at a frequency of 508.58 MHz since 1997. In the upgrade of the SPring-8, a beam energy is lowered from 8 to 6 GeV and a needed voltage is 7 MV. The upgrade employs multi-bending optics, and shortens the straight sections available for RF accelerating cavities by 30%. On account of the space, the RF system is to be so rearranged that the number of cavities can be reduced to half. The analog low-level RF (LLRF) system in use controls the voltage with sufficiently small deviations of less than 0.1 % in amplitude and less than 0.1 degree in phase, but becomes out-of-dates and hard to be maintained. We plan to replace them with a compact digital LLRF system in the MTCA.4 standard and based on under-sampling scheme. The SACLA linac is used for injecting a low-emittance beam to the ring. Because we have to balance the FEL operation and the beam injection on demand, pulse-by-pulse control of beam parameters is going to be implemented to the SACLA LLRF modules. Furthermore, we build a timing system for injection to a target bucket-position in the ring within a time deviation of 3 ps., Proceedings of the 7th Int. Particle Accelerator Conf., IPAC2016, Busan, Korea

2006年度から、文部科学省が推進するスーパー・サイエンス・ハイスクール(以下SSH)の指定を受けた。本稿では、第2年次の取り組みの概要と目標を中心にまとめた。具体的には、サイエンス・リテラシーを育む教育課程、キャリア意識を育む教育課程、生徒研究員制度、多面的教育評価、協同的探究学習法、中間評価としてのSSH研究協議会の概要と目標を簡潔にまとめた。最後に、第2年次の実施上の課題と今後の取り組みについても簡潔に示した。, 国立情報学研究所で電子化したコンテンツを使用している。

BACKGROUND: Edwardsiella tarda bacteremia (ETB) can be a fatal disease in humans.OBJECTIVES: To determine the significant risk factors associated with death caused by ETB, and to examine the geographical, seasonal, environmental and dietary factors of the disease.METHODS: A retrospective, observational, case control study was performed. The PubMed MEDLINE and Japanese Medical Abstract Society (www.jamas.or.jp) databases were searched for ETB case reports and meeting abstracts. In additon, retrospective chart reviews of patients with ETB at the Tokyo Women’s Medical University Hospital (Tokyo, Japan) were conducted to evaluate the risk factors associated with death using multivariate analyses.RESULTS: The literature search yielded 46 publications, comprising 72 cases from the English (n=30), French (n=1), Spanish (n=1) and Japanese (n=14) literature. Five cases at the Tokyo Women’s Medical University Hospital were also included. Of the included 77 cases, the mean age was 61 years and 39% of patients were female; 77.2% of the cases occurred between June and November, and 45.5% were reported in Japan. Dietary factors (raw fish/meat exposure) were reported for 10.4% of patients and 12.9% reported environmental (ie, brackish water) exposure. The overall mortality rate was 44.6%; however, this rate increased to 61.1% for ETB patients with soft tissue infections. Liver cirrhosis was determined to be an independent risk factor associated with death (OR 12.0 [95% CI 2.46 to 58.6]; P=0.00213) using multivariate analyses.DISCUSSION: To our knowledge, the present analysis was the first and largest multi-language review of ETB. Clinical characteristics of ETB resemble those of Aeromonas, typhoid fever and Vibrio vulnificus infections, in addition to sharing similar risk factors.CONCLUSION: ETB should be categorized as a severe food- and waterborne infection, which results in high mortality for patients with liver cirrhosis.

A 70-year-old man with a history of tongue cancer presented with Fournier’s gangrene caused by Listeria monocytogenes serotype 4b. Surgical debridement revealed undiagnosed rectal adenocarcinoma. The patient did not have an apparent dietary or travel history but reported daily consumption of sashimi (raw fish).Old age and immunodeficiency due to rectal adenocarcinoma may have supported the direct invasion of L monocytogenes from the tumour. The present article describes the first reported case of Fournier’s gangrene caused by L monocytogenes. The authors suggest that raw ready-to-eat seafood consumption be recognized as a risk factor for listeriosis, especially in cases of skin and soft tissue infection.

平成17年度から始まった「学びの社・学術コース」の特色と、学習目標を明確にし、平成17年度に開講された講座と講座内容を掲載した。この大学連携講座の成果と課題を、附属学校で実施した「学びの力」に関するアンケート調査の結果から明らかにした。成果としては、「探究する力」と「自分を知る力」について、自己認識レベルではあるが、「学ぶ知識の広がり」と「自分の将来を自覚的に選択する力」を育む機会を提供できたことにある。課題としては、人数や講義形式の制限から「自ら課題を設定したり」、「表現する力」を充分に育成する機会となっていないと認識していることである。, 国立情報学研究所で電子化したコンテンツを使用している。

An ultimate storage ring (USR) is being designed at synchrotron radiation facilities in the world. USR can generate theoretically minimum synchrotron radiation because emittance of the USR is less than diffraction limit of the radiation. The USR requires high alignment precision of micro-meter order. A vibrating wire method (VWM) has widely been used for such a high precision alignment. An error field of multi-pole magnet is estimated by detecting a vibration of a single wire excited with AC current. The wire position, where no vibration is excited, is defined as the magnetic center. The applied frequency is kept on a resonant frequency, which may drift due to temperature change etc. during the measurement. To trace the resonant frequency at all times, we developed a frequency feedback system. It is necessary to trace the resonance, even when the wire is set in the vicinity of the magnetic center where the magnetic field is nearly zero. Here we propose to install one or two additional wires parallel to the original wire. The additional wires off the center can detect the vibration frequency with enough S/N ratio. We discuss the effectiveness of it for quick and reliable alignment., Proceedings of the 5th Int. Particle Accelerator Conf., IPAC2014, Dresden, Germany

SPring-8 is a 3rd generation light source which has been operated stably. During user operation, an interlock system which turns off the RF acceleration signal if the beam orbit at insertion devices exceed a window is in operation. Beam abort events due to the interlock system have occurred as a rare event at SPring-8. Though in most cases we find trouble in accelerator devices as the source of the beam orbit shift, sometimes we cannot find any evidence after the beam abort. In order to identify the sources of such aborts, we have developed a system which observe beam orbit along the storage ring during beam abort. The system was realized by modification of the digital part of the existing COD measurement system. Every 1 ms, the system measures beam position at all BPMs with the position resolution of 1 micron or less. This system enabled us to identify the source when a beam abort due to an orbit shift with a time constant of longer than a few milliseconds. Furthermore, this system is applicable to survey sources of beam orbit fluctuations during stable operation. In this proceeding, we describe the system, beam orbit data during beam abort and source analysis., Proceedings of the 5th Int. Particle Accelerator Conf., IPAC2014, Dresden, Germany

At the Affiliated Upper and Lower Secondary Schools, School of Education, Nagoya University, a lot of curriculum developments have been attempted, however there is concern about the decline in the levels of academic attainment of the students. Meanwhile, in School of Education, there are discussions about the separation between practice and theory at the educational science field. Until now, even undergraduate/graduate students belonging to School of Education have not had enough opportunity to experience the practical educational settings. To resolve these problems stated above, we established the project of individual instruction assisted by voluntear students. In the project, an undergraduate/graduate of the School of Education as a tutor instructed Mathematics or English to a lower secondary school student for about an hour once or twice a week. Several meetings were held by the tutors participating in this project and full-time teachers of English and Mathematics. The main purpose of the meetings was to exchange some ideas and opinions about individual instruction. As a result of having conducted this project for a semester, we discussed about some viewpoints in the future : 1. to clarify the purpose of this class, 2. systematization of this class, 3. improvement of interpersonal relationship between students and tutors, and that of corporate finances to support our project., 国立情報学研究所で電子化したコンテンツを使用している。

国立情報学研究所で電子化したコンテンツを使用している。

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