Derivation of CPT resonance signals from density-matrix equations with all relevant sublevels of Cs atoms and confirmation of experimental results

Coherent-population-trapping resonance is a quantum interference effect that appears in the two-photon transitions between the ground-state hyperfine levels of alkali atoms and is often utilized in miniature clock devices. To quantitatively understand and predict the performance of this phenomenon, it is necessary to consider the transitions and relaxations between all hyperfine Zeeman sublevels involved in the different excitation processes of the atom. In this study, we constructed a computational multi-level atomic model of the Liouville density-matrix equation for 32 Zeeman sublevels involved in the $D_1$ line of $^{133}$Cs irradiated by two frequencies with circularly polarized components and then simulated the amplitude and shape of the transmitted light through a Cs vapor cell. We show that the numerical solutions of the equation and analytical investigations adequately explain a variety of the characteristics observed in the experiment.Comment: 24 pages, 8 figure

Serum levels of soluble Fas/APO-1 (CD95) and its molecular structure in patients with systemic lupus erythematosus (SLE) and other autoimmune diseases

There are two major forms of the Fas molecule, membranous Fas and soluble Fas (sFas). To clarify the clinical significance of sFas in autoimmune diseases, we designed a sandwich ELISA to determine serum concentrations of sFas and its molecular structure, and we then analysed the correlation between levels of sFas and laboratory findings in patients with SLE and other autoimmune diseases. The levels of serum sFas were significantly higher in SLE patients than in subjects with other autoimmune diseases and in healthy donors, and the frequency of a positive serum sFas was much greater in SLE patients with high SLE disease activity index scores than in those with low scores. In addition, sFas-positive SLE patients showed a significant difference in various laboratory parameters from sFas-negative SLE patients. Serial measurements of serum sFas levels in SLE patients with active disease revealed that the elevated level of sFas dramatically decreased with improvement in clinical and laboratory findings, following corticosteroid therapy. We propose that the serum level of sFas can serve as an appropriate marker for evaluating SLE disease activity. Serum sFas is heterogeneous with respect to molecular structure, thus several mechanisms are involved in the generation of sFas

Development of the compact VLBI system for calibrating GNSS and EDM devices

We are developing a compact VLBI (Very Long Baseline Interferometry) system with 1.6 m diameter aperture dish in order to provide reference baseline lengths for calibration. The reference baselines are used to validate surveying instruments such as GPS (Global Positioning System) and EDM (Electro-Optical Distance Measurement) and maintained by the Geospatial Information Authority (GSI) of Japan. The compact VLBI system is designed to be assembled with muscle power simply in order to perform short-term (about one week) measurements at several reference baselines in Japan islands. First, we have evaluated a front-end system with a wideband quad-ridged horn antenna by installing it on the 2.4 m diameter antenna at Kashima as a feasibility study. We have successfully carried out five geodetic VLBI experiments using it during September 2006 to July 2008. In addition we have concluded the new analysis concept to obtain indirectly the group delays on the baseline between two compact dishes is available. Next, we have carried out the VLBI experiments on the Kashima-Tsukuba baseline (about 54 km) using the two compact VLBI system during December 2009 to October 2010. The averaged baseline length and repeatability of the experiments is 54184875.1 ±2.5 mm

An adaptive supramolecular hydrogel comprising self-sorting double nanofibre networks

特定の刺激でタンパク質放出速度を制御、スマート超分子ヒドロゲルの開発. 京都大学プレスリリース. 2018-01-10.Novel soft materials should comprise multiple supramolecular nanostructures whose responses (for example, assembly and disassembly) to external stimuli can be controlled independently. Such multicomponent systems are present in living cells and control the formation and break-up of a variety of supramolecular assemblies made of proteins, lipids, DNA and RNA in response to external stimuli; however, artificial counterparts are challenging to make. Here, we present a hybrid hydrogel consisting of a self-sorting double network of nanofibres in which each network responds to an applied external stimulus independent of the other. The hydrogel can be made to change its mechanical properties and rates of release of encapsulated proteins by adding Na2S2O4 or bacterial alkaline phosphatase. Notably, the properties of the gel depend on the order in which the external stimuli are applied. Multicomponent hydrogels comprising orthogonal stimulus-responsive supramolecular assemblies would be suitable for designing novel adaptive materials