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This paper describes laser-assisted film transfer technology for barium strontium titanate (BST) deposited on a sapphire substrate. BST is a promising ferroelectric material for varactors, which are required for frequency-tunable RF applications. However, the deposition temperature of BST (600 ~ 700 °C) is too high for surface acoustic wave (SAW) substrates. In this study, BST grown on a sapphire substrate at 650 °C was transferred at low temperature (140 °C) to a borosilicate glass substrate as well as a LiTaO3 substrate. The transferred BST films were characterized as tunable capacitors. A key process in the BST film transfer technology is the laser pre-irradiation of a buffer Pt layer beneath BST from the backside of the sapphire substrate to weaken the BST-to-Pt adhesion. The mechanism of delamination at the BST/Pt interface is discussed using a simple 1D heat transfer model. [ABSTRACT FROM AUTHOR]

A cognitive radio system requires a tunable filter with a wide tunable range to compose a simple front-end. Because the tunable range is limited by the bandwidth (BW) of resonators, an ultra-wideband resonator is an important device to implement the tunable filter. The authors previously obtained low frequency resonators with a wide BWs of 26 to 29% and a large impedance ratios of 92 to 98 dB between resonance (fr) and anti-resonance frequencies (fa) using 0-th mode shear horizontal (SH0 mode) plate wave in a LiNbO3 plate. Also, a tunable filter with the tunable range of 13% was demonstrated. However, the frequency (fr =1.8 MHz and fa = 2.3 MHz) is too low for modern wireless communication. Also, the resonators suffered from ripples due to transverse mode between fr and fa. In this study, high frequency SH0 mode plate wave resonators (fr = 430–560 MHz and fa = 530–670 MHz) with a wide bandwidth and a large impedance ratio have been fabricated using an ultrathin LiNbO3 plate. The ripples were suppressed by an apodized interdigital transducer. [ABSTRACT FROM AUTHOR]

This paper reports on moment detection by three integrated tactile sensors that detect 3-axis forces. In this study, the three integrated tactile sensors were connected along a serial bus andwere mounted in a triangle shape on a circuit board. Out-of-plane moment applied on the circuit boardwasmeasured using the shearing forces and a geometric relationship of the triangle sensor allay. The principle of the proposed moment detection method was demonstrated. The experimental results showed that the sensitivity and the nonlinearity were 1.10 count/N·m and ±16% full scale, respectively. The resolution of the obtained moment was below 0.015 N·m. The moment detection ability enables the partner robots to grasp objects correctly and to interact softly with human. [ABSTRACT FROM AUTHOR]

Stimulated human monocytes release several proteins thought to play a role in inflammation, including interleukin 1, tumor necrosis factor, and plasminogen activator. We have purified another proinflammatory protein that is chemotactic for human neutrophils from conditioned medium of lipopolysaccharide-stimulated monocytes. After a series of steps that included anion-exchange chromatography, gel nitration, and HPLC on cation-exchange and reverse-phase columns, an apparently pure protein was obtained that migrated as a single 7-kDa band on NaDodSO4/polyacrylamide gels under reducing or nonreducing conditions. The amino acid composition of this monocyte-derived neutrophil chemotactic factor was different from that of interleukin 1 and tumor necrosis factor. N-terminal amino acid sequence of the first 42 residues was determined. This portion of the molecule has up to 56% sequence similarity with several proteins that may be involved in host responses to infection or tissue injury. It is identical to a portion of a sequence deduced from an mRNA induced by staphylococcal enterotoxin treatment of human leukocytes. At the optimal concentration of 10 nM, 50% of neutrophils added to chemotaxis assay wells migrated toward the pure attractant. Potency and efficacy are comparable to that of fMet-Leu-Phe, which is often used as a reference. In contrast to many attractants, the protein was not chemotactic for human monocytes. [ABSTRACT FROM AUTHOR]

This article presents information on the highly stereoselective and regioselective Ni-catalyzed homoallylation of aldimines with conjugated dienes promoted by diethyizinc. Certain combination of reagents, Ni(acac)2 and Et2Zn, works for the homoallylation of aldimines. The reaction is remarkable in many respects. First, the reaction proceeds with an opposite sense of stereoselectivity to that of aldehydes, providing 1,3-syn-2 selectivity. Regio selectivity with respect to dienes (C1 or C4) is slightly lower than that observed for aldehydes, and isomers are produced as minor products.