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We determined whether a major Japanese cedar pollen allergen (Cry j 1) conjugated with CpG oligodeoxynucleotide would enhance allergen-specific Th1 responses in mice. Cry j 1 conjugated with CpG (Cry j 1-CpG) induced IL-12 in the spleen cells of naïve mice. Cry j 1-CpG immunization of BALB/c mice suppressed anti-Cry j 1 IgE response and enhanced anti-Cry j 1 IgG(2a) to subsequent Cry j 1 and alum adjuvant injection. CD4(+)T cells isolated from the spleens in mice immunized with Cry j 1-CpG produced higher IFN-γ levels than did CD4(+)T cells obtained from mice as negative controls. Our results suggested that Cry j 1-CpG immunization can induce Cry j 1-specific Th1 immune responses, thereby inhibiting IgE response to the pollen allergen.

A superconducting electron cooler with an adiabatic expansion factor of 100 was designed for high-precision experiments and high-speed cooling. The gun solenoid is a liquid-helium-free superconducting magnet with a 20-cm room-temperature bore, which can produce a magnetic field of up to 3.5 T. An electron beam is expanded from a diameter of 5 to 50 mm in a gradually decreasing solenoid field from 3.5 T to 35 mT. With this cooler, a transverse electron temperature on the order of 1 meV was attained. The longitudinal cooling force was measured with an induction accelerator as functions of the ion and electron currents, and the expansion factor. The longitudinal cooling force does not depend much on the expansion factor.

In cooler-ring experiments, an accurate and non-destructive current measurement is essential for determining the reaction cross sections. The lowest current which can be measured by the DC current transformer commonly used so far is some μA. In order to measure a low-beam current from nA to μA, we made a cryogenic current-measuring device using a superconducting quantum interference devices (SQUID), and measured the circulating ion current at the cooler ring TARN II. This paper gives the design and performance of the device.

At the cooler-synchrotron TARN II, light- and heavy-ion beams are stored, electron-cooled and accelerated for the research of atomic physics and accelerator studies. In these experiments, the closed orbit distortion (COD) correction system plays an important role for improving the beam currents and lifetimes. In order to measure the position of a circulating faint beam in the ring, we developed beam diagnostic devices of high sensitivity and low noise. The beam positions can be measured with an accuracy of 0.3 mm at a circulating beam current of 1 μA. It is the purpose of the present paper to describe details concerning the beam position monitor (BPM) system, an investigation of the sensitivities of the BPM from the point of view the S N ratio, the experimental results of a COD correction and measurements of the accelerator parameters, such as the chromaticity and dispersion using this system.

A light and heavy ion synchrotron with an electron cooling system, TARN-II, has been operated for the studies of atomic physics and accelerator technology. After the upgrading of the pump system by adding ion pumps and titanium getter pumps in 1991, and non-evaporable getter pumps based on St 707 in 1994, an average pressure of the order of 10 −9 Pa has been achieved. Molecular ion beams such as H 2 + , H 3 + , HD + , HD 2 + , HeH + and HeD + have been stored in the ring for the experiments of collision between molecular ions and electrons. A beam life time of 5 s was measured for HD + ions at an average pressure of 7 × 10 −9 Pa. The performance of the system is presented.

The heavy ion cooler synchrotron, TARN-II, has been operated for studies of accelerator technology and atomic physics since 1989 at the Institute for Nuclear Study, University of Tokyo. The ring has a circumference of 78 m and the vacuum pipe is made of SUS 316L stainless steel. The vacuum system consists of ion pumps, titanium sublimation pumps and turbo-molecular pumps. Beam experiments like acceleration, electron cooling, and extraction have been carried out at a mean pressure of the order of 10 −10 torr. In 1991, the upgrading of TARN-II vacuum system had been performed by adding ion pumps and titanium sublimation pumps in order to promote the experiments using heavy ion beams. Ion beams such as p, D, H 2 + , H 3 + , 3 He + , 4 He 2+ , HD 2 + , 4 HeH + , 14 N 5+ and 14 N 7+ have been injected and circulated in the ring so far.

A slow beam extraction system using the third order resonance has been constructed at TARN II and beam extraction tests have been performed. By the ordinary scheme where the tune is shifted to the resonance with ramping the excitation strength of the lattice quadrupole magnets, an extraction efficiency of 90% is attained. A new scheme increasing the horizontal emittance of the circulating beam is applied to extract the beam. A very long beam spill of 800 s is obtained by this scheme. A method using a transverse rf field is also studied experimentally, resulting in an extracted beam with smaller emittance.

An electron cooling device with a maximum energy of 110 keV was designed and constructed. The device was installed in the TARN II storage ring and electron cooling experiments have been performed for light ions. In this article, the design, construction and off-line electron beam test of the cooling device are presented. Then the electron cooling experiments on proton and the electron capture studies on H 2 + are described.

The test accumulation ring, TARN, had been constructed for the development of heavy ion acceleration, and the experiments of beam accumulation and stochastic cooling were performed successfully. TARN was converted into a new heavy ion ring, TARN II, which has a maximum energy of 1.1 GeV and 370 MeV u −1 for protons and heavy ions. The vacuum system was constructed for a residual pressure of better than 10 −8 Pa. Now, a pressure of 5 × 10 −8 Pa is achieved.

OR10,56 Insulin receptor substrate-1 localized around endosomes, sorted by adaptor protein-1 complex, transmits insulin/IGF signals to specific Akt substrates Y. Yoneyama, S. Yoshinaga, M. Matsuo, K. Take, S. Sato, T. Umehara, S. Yokoyama, T. Kabuta, K. Chida, F. Hakuno, S.-I. Takahashi. Departments of Animal Sciences and Applied Biological Chemistry, The University of Tokyo, Tokyo, Japan; System and Structural Biology Center, RIKEN, Yokohama, Japan

An isotope separator was constructed and operated with on-line connection to the INS FM cyclotron. The gas-discharge type ion source was used in the earlier stage. Later the ion source was improved to the hollow-cathode type in order to achieve high temperature and high efficiency. The mean radius and the deflection angle of the separator are 60 cm and 45°, respectively. Mass-separated ions are transported through concrete walls to a tape collector, where radioactivities are measured. As a test experiment, natural copper foils were bombarded with the 52 MeV proton beam, and the reaction products of 63 Zn, 62 Zn, 61 Zn and 60 Zn were separated. The delay time between production and measurement was shortened to 1 min for the Zn isotopes evaporated from the 10 μm Cu foil. Yield ratios of 61 Zn to 63 Zn were measured for proton energies of 30–47 MeV.

Cross sections of the reaction 63 Cu (p, 3n) 61 Zn (T 1 2 = 1.48 min ) have been measured for proton energies from 30 to 47 MeV with an isotope separator on-line (ISOL) attached to a cyclotron. The method of the cross section measurement with the ISOL system has been developed. The cross sections obtained by the ISOL method agreed with those by the stacked foil method. In addition, cross sections of the 63 Cu (p, p3n) 60 Cu (T 1 2 = 24 min ) reaction have been measured by the stacked foil method at proton energies up to 52 MeV.