This paper describes the stimuli-responsive hydrogels constructed from bola-type amphiphiles composed of two dipeptides containing phenylalanine attached to the ends of a hydrophobic tetrathiophene. ...The hydrogel formation ability of the amphiphiles was affected by the N-terminal amino acid residue, which is an amphiphile-possessing phenylalanine-lysine sequence that formed a hydrogel under limited pH conditions. Gel formation occurred because of the phase transition of the gelator assembly from a granular aggregate to a fibrous architecture, in a process controlled by pH. This stimuli-responsive sol–gel transition was also accomplished by the addition of an anionic polymer, and sulfated glycosaminoglycans were successfully discriminated using the hydrogel system.A bola-type π-conjugated amphiphile containing Phe-Lys dipeptide showed a pH- and guest-induced phase transition from the granular aggregate to the fibrous architecture and formed a supramolecular hydrogel. Using this stimuli-responsiveness, the hydrogel system was successfully applied to the selective discrimination of glycosaminoglycans composed of a sulfated sugar unit.
Synopsis Measurements of Lamb shift in antihydrogen atom have been planned to extract the antiproton charge radius which has never been experimentally investigated. A hyperfine spin filter and a ...microwave cavity can be employed.
The human face and gaze direction elicit explicit attention in terms of the fixations that guide selective attention to visual information. We examine this possibility by tracking eye movements while ...participants twice viewed a video of a magic trick and demonstrate that participants fixate on the magician's face. During the first viewing, participant eye movements largely followed the objects that the magician had previously attended to. These results indicate that one's own fixations substantially guide the fixations of others. Even during the second viewing, when participants knew what to expect, they continued to be strongly influenced by the magician's gaze direction. This tendency was also observed even in the absence of explicit information concerning the magician's gaze direction due to wearing a mask. However, this bias gradually declined as the video continued. Accordingly, we argue that, when individuals must accurately infer the other person's intention to comprehend some video content, prior viewings are largely ineffectual in attenuating the other people's impact on controlling own fixation.
Antihydrogen research has been conducted aiming at a stringent test of the CPT symmetry. The strategy is "listen to the whisper of nature", where high precision spectroscopy of antihydrogen atoms is ...adopted as the potential tool to uncover the truth. This is in good contrast to a general approach to probe ultramicroscopical regions with high energy particle beams. Near the end of the last year (2010), two new achievements were reported in the field of cold antihydrogen research. They were trapping of antihydrogen atoms in a magnetic bottle and synthesis of antihydrogen atoms in a cusp trap, which can yield a spin-polarized antihydrogen beam. The research was recognized as the top of the Breakthoughs of the Year by Physics World Magazine and also by other scientific journals and newspapers. Here we briefly summarize these recent achievements as well as possible future directions.
We report on our new techniques which enabled confinement and accumulation of a large number of antiparticles-namely antiprotons and positrons-in an electromagnetic trap. Antiprotons provided at 5 ...MeV from the CERN Antiproton Decelerator (AD) ring were decelerated by an RFQ Decelerator and trapped in a Multi-Ring Trap (MRT) under 2.5T magnetic field. This combination enabled us to trap millions of antiprotons, with an efficiency 50 times better than a typical efficiency achieved with thick degrader foils. Diagnosis and control of an electron plasma preloaded in the trap enabled non-destructive monitoring of cooling process of the antiproton cloud. It led us to succeed in extracting antiprotons out of the trap as a monoenergetic beam at 10-500eV, which can be used to study ionization and capture processes of the antiprotons under single collision conditions for the first time. A new positron accumulation scheme has been invented, where a dense electron plasma is employed as an energy absorber. The new accumulation system consists of a 22Na positron source with a solid Ne moderator, a MRT for electrons and positrons housed in a 5T superconductor magnet, and a tungsten re-moderator. This system is fully compatible with ultra-high vacuum. The positron accumulation efficiency normalized by the positron source intensity was ∼10-5e+/s/Bq, at least 30 times higher than ever realized under ultra-high vacuum conditions. With these techniques of manipulating ultra slow antiparticles, we are about to open up a new field of antimatter physics such as the synthesis of spin-polarized antihydrogen atoms, antiprotonic atoms.
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