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A translation experiment of field-reversed configuration (FRC) plasma is performed on the FIX machine [Shiokawa and Goto, Phys. Fluids B 5, 534 (1993)]. The translated FRC bounces between magnetic mirror fields at both ends of a confinement region. The plasma loses some of its axial kinetic energy when it is reflected by the magnetic mirror field, and eventually settles down in the confinement region. In this reflection process, the plasma temperature rises significantly. Such plasma rethermalization has been observed in OCT-L1 experiments [Ito et al., Phys. Fluids 30, 168 (1987)], but rarely in FRX-C/T experiments [Rej et al., Phys. Fluids 29, 852 (1986)]. It is found that the rethermalization depends on the relation between the plasma temperature and the translation velocity. The rethermalization occurs only in the case where the translation velocity exceeds the sound velocity. This result implies the rethermalization is caused by a shock wave induced within the FRC when the plasma is reflected by the magnetic mirror field.

Sputtering yields and surface modification of poly(methyl methacrylate) (PMMA) by mono-energetic ion beams and/or vacuum ultraviolet (VUV) light are studied with the use of a low-energy mass-selected ion beam system. Sputtering yields of PMMA by Ar+ or ion beams are obtained as functions of ion incident energy below 500 eV. It is found that surface modification of PMMA due to ion incidence is limited to the region near the film surface, whereas that due to Ar+ ion incidence is seen in a relatively deeper region of the film, where PMMA is partially carbonized and diamond-like carbon (DLC) is formed. Under the conditions of incident energies and fluxes of ion and VUV light used in the experiments, the sputtering yield of PMMA by simultaneous incidence of VUV light and ions is found to be nearly equal to the sum of the yields by separate incidences of VUV light and ions. Some of the etching characteristics observed in this study (such as DLC formation by ion sputtering) may be shared by a wide range of organic polymers that have main chain structures similar to those of PMMA.

Proteasome assembling chaperone (PAC) 3 acts as a homodimer and plays an important role in proteasome formation. We screened JBIR-22 (1) as an inhibitor for protein-protein interaction (PPI) of PAC3 homodimer from our natural product library using a protein fragment complementation assay (PCA) with monomeric Kusabira-Green fluorescent protein (mKG) in vitro and found that 1 exhibited potent inhibitory activity against PAC3 homodimerization. Compound 1 showed long-term cytotoxicity against the human cervical carcinoma cell line, HeLa. This is the first report of a PPI inhibitor for proteasome assembly factors.