Many proteins undergo post-translational modification via well defined mechanisms such as acetylation, phosphorylation and glycosylation and thereby control a spectrum of biochemical processes. A growing body of evidence suggests that the reversible reduction of disulfide bonds also alters the structure and activity of proteins. Thioredoxin, a ubiquitous 12 kDa protein with a catalytically active disulfide active site (Cys-Gly-Pro-Cys), plays a central role in controlling the redox status of disulfide bonds in proteins that regulate a range of processes. Included are photosynthesis, seed germination, transcription, cell division, radical scavenging and detoxification. The ability to identify unknown functions of proteins of all types has been advanced by the emerging field of functional proteomics. In this brief review, we introduce the disulfide proteome as a tool that complements other methods for the comprehensive analysis of proteins. In so doing, the usefulness of applying this method for both in vitro and in vivo analyses is discussed for thioredoxin and other disulfide proteins, especially those occurring in plants.

A novel scheme for the focusing of high-energy leptons in future linear colliders was proposed in 2001 [P. Raimondi and A. Seryi, Phys. Rev. Lett. 86, 3779 (2001)]. This scheme has many advantageous properties over previously studied focusing schemes, including being significantly shorter for a given energy and having a significantly better energy bandwidth. Experimental results from the ATF2 accelerator at KEK are presented that validate the operating principle of such a scheme by demonstrating the demagnification of a 1.3 GeV electron beam down to below 65 nm in height using an energy-scaled version of the compact focusing optics designed for the ILC collider.

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For high luminosity in electron-positron linear colliders, it is essential to generate low vertical emittance beams. We report on the smallest vertical emittance achieved in single-bunch-mode operation of the Accelerator Test Facility, which satisfies the requirement of the x-band linear collider. The emittances were measured with a laser-wire beam-profile monitor installed in the damping ring. The bunch length and the momentum spread of the beam were also recorded under the same conditions. The smallest vertical rms emittance measured at low intensity is 4 pm at a beam energy of 1.3 GeV, which corresponds to the normalized emittance of 1.0x1.0(-8) m. It increases by a factor of 1.5 for a bunch intensity of 10(10) electrons. The measured data agreed to the calculation of intrabeam scattering within much better than a factor of 2.

A systematic compositional and structural study of GaN : Mn epilayers grown by molecular beam epitaxy (MBE) was performed, with a special attention to the dependence on the growth conditions. The ''growth diagram" related to the Ga/N flux ratio for GaN was modified by adding Mn flux. In particular, the stable Ga-bilayer coverage on the surface for the Ga-rich condition was reduced in the presence of Mn. The Mn incorporation in the epilayers was found to be strongly dependent on the Ga/N flux ratio. The X-ray diffraction (XRD) and extended X-ray absorption fine structure (EXAFS) measurements revealed a clear contrast between the precipitation of a perovskite compound GaMn 3 N at Mn compositions higher than 1:7%, and the single phase of the wurtzite Ga 1Àx Mn x N at lower Mn compositions. The single-phase epilayers (x 1:7%) exhibited intrinsic ferromagnetic behaviors at room temperature.Nitride compounds are being applied to the devices of short-wavelength optics and high-power electricity, but their potential application is not limited to these fields. Quite recently, nitride compounds with the incorporation of magnetic elements have been expected to be crucial materials for spin-electronics. For GaN with the incorporation of 5% of Mn, a ferromagnetic transition beyond room temperature has been theoretically predicted [1]. Experimentally, it was reported that GaN : Mn films grown by MBE exhibit ferromagnetic character above room temperature [2]. However there were other works reporting that it remains paramagnetic down to low temperatures [3]. Moreover it has not been confirmed whether the single phase of ternary compounds Ga 1Àx Mn x N, in which Mn atoms randomly substitute the Ga site in the wurtzite GaN, really exhibits ferromagnetism or not. The present controversial situation seems to be due mainly to the unresolved problem of a possible precipitate of manganese compounds in other phases than the purely diluted phase of Ga 1Àx Mn x N [4,5].In the present study, we have grown wurtzite GaN : Mn epilayers and have performed their characterizations by various methods. A special attention was paid to the different growth regimes related to the Ga/N flux ratio. We have studied the compositional and structural properties by secondary ion mass spectroscopy (SIMS), X-ray diffraction (XRD) and extended X-ray absorption fine structure (EXAFS) and investigated their correlation with the above growth regimes.

ATF2 is a final-focus test beam line which aims to focus the low emittance beam from the ATF damping ring to a vertical size of about 37 nm and to demonstrate nanometer level beam stability. Several advanced beam diagnostics and feedback tools are used. In December 2008, construction and installation were completed and beam commissioning started, supported by an international team of Asian, European, and U.S. scientists. The present status and first results are described

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