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properties of biological synapses and perform parallel operations, they require larger energy than a biological synapse. Therefore, development of an artificial synapse with energy consumption on the level of a biological synapse remains an open problem.Organic-inorganic halide perovskite (OHPs) may provide a material to solve this problem, because of their low activation energy of ion migration. Moreover, various structural modulation of polycrystalline films is possible with facile solution processing so that organic parts in the OHPs can control the ion migration and electrical conduction. OHPs have an ABX 3 crystal structure; the A-site cation is located at the center of a BX 6 octahedral cage, and the B-site metal cation is surrounded by the six nearest-neighbor X-site halide anions. [7] OHPs have a significant hysteresis property that is caused by ion migration or space charges, or both, which may enable gradual modulation of conductance in OHP. [8] Two-terminal artificial synapses based on 3D methylammonium (MA) lead halide perovskite (MAPbX 3 , X = Br, I) films showed synaptic responses that are caused by ion migration in the OHP layer. [9,10] Ion migration in 3D OHP film is induced by relatively low activation energy and a low energy consumption of ≈20 fJ per synaptic event was achieved in the synaptic devices. However, the energy consumption could be further reduced to the energy level of biological synapses when the ion migration was controlled by engineering the structure of OHP films could be optimally done.In this work, we introduce 2D and quasi-2D OHP films into artificial synapses to enable control of ion migration and resultant synaptic responses. For this purpose, we replaced the small MA ion with a bulky phenethylammonium (PEA) ion in their crystalline structures. To prepare 2D, quasi-2D, and 3D OHP films, we controlled the stoichiometric ratio of PEA and MA cations to induce self-assembly of a layered structure. This replacement of an MA cation with PEA cation suppresses ion migration in the out-of-plane direction of the OHP films. [11][12][13] Thereby, the activation energy E A of ion migration is increased, so ion migration and excitatory postsynaptic current (EPSC) can be reduced. Also, energy consumption of the device is reduced to ≈0.7 fJ per synaptic event, which is comparable to that of biological synapses. Memory retention of artificial The hysteretic behavior of organic-inorganic halide perovskites (OHPs) are exploited for application in neuromorphic electronics. Artificial synapses with 2D and quasi-2D perovskite are demonstrated that have a bulky organic cation (phenethylammonium (PEA)) to form structures of (PEA) 2 MA n-1 Pb n Br 3n+1 . The OHP films have morphological properties that depend on their structure dimensionality (i.e., n value), and artificial synapses fabricated from them show synaptic responses such as short-term plasticity, paired-pulse facilitation, and long-term plasticity. The operation mechanism of OHP artificial synapses are also analyzed depending on the dimen...

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Objective. Bone destruction is a critical pathology involved in the functional disability caused by rheumatoid arthritis (RA). Osteoclasts, which are specialized bone-resorbing cells regulated by cytokines such as RANKL, are implicated in bone destruction in RA. The aim of this study was to determine whether interleukin-21 (IL-21), a potent immunomodulatory 4-␣-helical bundle type 1 cytokine, has osteoclastogenic activity in patients with RA and in mice with collageninduced arthritis (CIA).Methods. The expression of IL-21 in synovial tissue was examined using immunohistochemistry. The concentrations of IL-21 in serum and synovial fluid were determined by enzyme-linked immunosorbent assay.

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previous research investigating the encoding. encoding-plus-storage, and external-storage fnncticns of note taking has failed to equate processing oppottunities among the groups. The present studies did so by having the encoding group take notes at two occasions without review, the encoding-plus-storage group take notes one time and review notes the next, and the external-storage group twice review a set of borrowed notes. Three forms of note taking were used: conventional, and note taking on skeletal and matrix frameworks.In both Experiment 1, involving lecture learning, and Experiment 2, involving text learning, an advantage was found for the encoding-plus-storage function on tests involving factual-recall and recognition performance but not on tests measuring higher-order perfommnce.With respect to note-taking forms, no advantage existed for any form when information was aquired fran lecture. When text material was used there was some advantage for conventional notes and a clear advantage for not taking notes at all, but instead twice reading the material. These findings were explained relative to observed note-taking behaviors, the opportunity for review, and the processing demands proposed by the combination of reading and note taking, particularly when notes must be classified into an existing framework.

The binding property of p-biphenyl isocyanide self-assembled monolayers (SAMs) on Au and Ag was investigated by temperature-dependent surface-enhanced Raman spectroscopy (SERS). p-Biphenyl isocyanide was found to desorb on Ag at a low temperature of ∼393 K whereas it appeared to remain enduring at a high temperature of ∼453 K for Au. Structures of p-biphenyl isocyanide SAMs on Au and Ag flat films were checked by means of near-edge x-ray absorption fine structure spectroscopy (NEXAFS) at the two different normal (90• ) and grazing (20 • ) angles of the incident x-ray beam. Our results suggested that the SAMs prepared by p-biphenyl isocyanide should have a relatively disordered structure even at room temperature on both Au and Ag, as indicated from an insubstantial change in NEXAFS spectra at the two different angles from those of p-biphenyl thiolate and p-biphenyl methanethiolate. The weakness of the isocyanide-metal bond in comparison with the sulphur-metal bond may result in both low surface coverage and orientational disorder. A density functional theory calculation method was employed to attempt to explain the difference in stability for phenyl isocyanide on Ag and Au surfaces. Our calculation result yielded a lower binding energy of phenyl isocyanide on Ag than that on Au, consistent with the temperature-dependent Raman results.