The proton dynamics of poly(4-hydroxystyrene) (PHS) films were investigated using Coumarin 6 (C6). The acid density was 0.022 nm À3 at the exposure dose of 10 mC cm À2 (75 keV electron beam). The absorption intensity of C6 proton adducts was saturated at a certain concentration of C6, indicating an almost complete addition of protons at this C6 concentration. Protons can move in PHS films near C6 molecules even at room temperature. Also, the absorbed dose was estimated using 60 Corays. The acid yield can be well explained by an acid generation model involving the ionization of a base polymer.

The quantum defect method, generalised to the spin-orbit coupling scheme, has been used to calculate the oscillator strengths of the principal series for atomic caesium, taking into account the core polarisation produced by the valence electron. The good agreement obtained with respect to experimentally measured values has led us to carry out new calculations of generalised two-photon ionisation cross sections for the atomic caesium 6s ground state with linearly and circularly polarised incident radiation in the deep minimum region, related to destructive interferences, near the intermediate 7P resonance. A theoretical method previously developed was used; excellent agreement was obtained with respect to recent experimental data. The degree of spin polarisation of the ejected electrons has been calculated in the same region of incident photon energy.

With the shrinkage of patterns, the elucidation of reaction mechanisms at the molecular level has become essential in resist design. In particular, proton dynamics is one of the most important issues on the sensitivity and resolution of chemically amplified resists. In chemically amplified resists for post-optical lithographies, such as extreme ultraviolet and electron beam lithographies, it has been reported that protons mainly come from not acid generators but polymers. Determining proton sources is a key to understanding reaction mechanisms at the molecular level. In this article, we investigated the deprotonation mechanism of poly(4-hydroxystyrene) and poly(4-methoxystyrene) upon exposure to ionizing radiation. We found that the difference between the proton labilities of polymer radical cations (proton source for acid generation) leads to a difference in acid yield.

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These results indicate that intrathyroidal Treg cells are decreased in response to apoptosis in patients with AITD. This decrease in Treg cells may contribute to the incomplete regulation of autoreactive T cells in AITD.