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The behavior of the magnetoresistance (MR) effect in a ferromagnetic Ni nanocontact is investigated in the regime of conductance quantization (1/12900 /spl Omega//sup -1/). The giant MR effect is observed in the case that the nanocontact with quantized conductance is fabricated. We sometimes observe that the conductance discretely changes by the quantization unit of e/sup 2//h and that the quantized conductance is switched by the application of magnetic field. There exists a close relationship between nanocontact MR and quantized conductance.

Strong motion records from the South Hyogo earthquake of January 17, 1995, are overviewed. The discussion is focused on (1) the characteristic of near field records including the predominant direction of motion versus the fault strike and their spectral characteristic, and (2) the orientation error of seismometers and ground motion amplification at borehole array stations. Two numerical techniques for seismic response analysis of ground are applied for the array stations. The one is the frequency-dependent equi-linearized technique for the frequency domain analysis, and the other is the effective stress-based liquefaction analysis method. The numerical calculations are compared with the records at four borehole array stations.

The orientation error of accelrographs in borehole array stations was discussed using the records obtained during the South Hyogo Earthquake of Jan. 17, 1995. The four stations, three of them looted on reclaimed land and the other on stiff ground, were selected The displacement orbits on the horizontal plane were carefully examined, and significant orientation errors were detected The significance of the correction of orientation error was discussed The effective stress-based 2D and/or 3D liquefaction analyses were applied for one of the array stations. It was demonstrated that the method could reproduce the records well in the case that the orientation-corrected base motion was used as the input motion.

Spin waves (SWs) have the potential to reduce the electric energy loss in signal processing networks. The SWs called magnetostatic forward volume waves (MSFVWs) are advantageous for networking due to their isotropic dispersion in the plane of a device. To control the MSFVW flow in a processing network based on yttrium iron garnet, we developed a SW absorber using artificial structures. The mechanical surface polishing method presented in this work can well control extrinsic damping without changing the SW dispersion of the host material. Furthermore, enhancement of the ferromagnetic resonance linewidth over 3 Oe was demonstrated.

We measured magnon densities during spin-wave interference using microfocused Brillouin light scattering spectroscopy. Spatial mapping of the magnon density revealed that the spin-wave interference is confined in the central region of the microwire and indicated the contribution of higher-order transverse quantized modes than those reported to date. A micromagnetic simulation revealed transverse 100 nm interference patterns, which affect the signal-to-noise ratio of magnonic logic operation. These results will provide a way to design integrated magnonic devices such as all-magnon transistors.

We demonstrate the time-resolved real-space observation of vortex gyration in a magnetic circular disc by X-ray magnetic circular dichroism photoemission microscopy at the SPring-8 beamline BL25SU, both with and without an additional structure called a pair tag, which serves to control the magnetic curling direction. By comparing the gyration orbits of the vortices, we found that the gyration properties are dependent on the presence of the additional structure in spite of the discs having the same diameter. Furthermore, we reproduced the vortex gyration by micromagnetic simulation. The confinement potential of the vortex can be controlled by the additional structure.

Porous amidoxime hollow fibers, which were prepared by radiation-induced graft polymerization of acrylonitrile onto porous polyethylene hollow fibers and subsequent amidoximation, were used as packing materials of the adsorption bed for uranium recovery from seawater. Seawater was forced to flow through the bed charged with the amidoxime hollow fibers either by pumping or by ocean current. Uranium concentration decay through the bed could be well correlated with residence time based on the adsorption rate expressed in terms of the overall mass-transfer coefficient. The resultant activation energy of 20 kcal/mol for uranium adsorption was indicative of the chelate formation of the amidoxime group with uranyl species as a rate-determining step.

In this study, we investigated the stability and structure of artificial base pairs that contain cyclohexyl rings. The introduction of a single pair of isopropylcyclohexanes into the middle of DNA slightly destabilized the duplex. Interestingly, as the number of the “base pairs” increased, the duplex was remarkably stabilized. A duplex with six base pairs was even more stable than one containing six A–T pairs. Thermodynamic analysis revealed that changes in entropy and not enthalpy contributed to duplex stability, demonstrating that hydrophobic interactions between isopropyl groups facilitated the base pairing, and thus stabilized the duplex. NOESY of a duplex containing an isopropylcyclohexane–methylcyclohexane pair unambiguously demonstrated its “pairing” in the duplex because distinct NOEs between the protons of cyclohexyl moieties and imino protons of both of the neighboring natural base pairs were observed. CD spectra of duplexes tethering cyclohexyl moieties also showed a positive–negative couplet that is characteristic of the B-form DNA duplex. Taken together, these results showed that cyclohexyl moieties formed base pairs in the DNA duplex without severely disturbing the helical structure of natural DNA. Next, we introduced cyclohexyl base pairs between pyrene and nucleobases as an “insulator” that suppresses electron transfer between them. We found a massive increase in the quantum yield of pyrene due to the efficient shielding of pyrene from nucleobases. The cyclohexyl base pairs reported here have the potential to prepare highly fluorescent labeling agents by multiplying fluorophores and insulators alternately into DNA duplexes.

We propose a hybrid prototyping approach that utilizes both virtual simulation and miniature simulation in designing spatial information systems such as public displays or sensors. In this paper, we describe a case study of the hybrid prototyping process and discuss roles of miniature space.

The performance of spintronic devices critically depends on three material parameters, namely, the spin polarization in the current ($P$), the intrinsic Gilbert damping ($\ensuremath{\alpha}$), and the coefficient of the nonadiabatic spin transfer torque ($\ensuremath{\beta}$). However, there has been no method to determine these crucial material parameters in a self-contained manner. Here we show that $P$, $\ensuremath{\alpha}$, and $\ensuremath{\beta}$ can be simultaneously determined by performing a single series of time-domain measurements of current-induced spin wave dynamics in a ferromagnetic film.

We measure the current and shot noise in a quantum dot (QD) in the Kondo regime to address the non-equilibrium properties of the Kondo effect. By systematically tuning the temperature and gate voltages to define the level positions in the QD, we observe an enhancement of the shot noise as temperature decreases below the Kondo temperature, which indicates that the two-particle scattering process grows as the Kondo state evolves. Below the Kondo temperature, the Fano factor defined at finite temperature is found to exceed the expected value of unity from the non-interacting model, reaching $1.8 \pm 0.2$., 4 pages, 4 figures

In this paper, we describe hybrid prototyping that combines virtual simulation with physical device, and argue the possibility of hybrid prototyping through a simulation of an augmented environment.

In this paper, we introduce CityCompiler, an integrated environment for the iteration-based development of spatial interactive systems. CityCompiler visualizes interactive systems in a virtual 3D space by combining the Processing source code and the 3D model of the real space, designed with Google SketchUp. A simulation in virtual space enables us to test a spatial layout and a combination of components. In addition, the system function of smoothly switching between a virtual sensor and a real sensor realizes hybrid prototyping by means of virtual simulation and miniature simulation. These features integrate the space design with the software design and allow the smooth deployment of spatial interactive information systems into the real world.

Quenched: Perylenediimide (PDI) is highly quenched by nucleobases, which greatly restricts its application as a fluorescent probe. Here, we propose "insulator base pairs" tethering cyclohexane ring through D-threoninol. When "insulator base pairs" were inserted between PDI and nucleobases, the quantum yield of PDI drastically increased several thousand-fold. The "insulator base pairs" reported here also have the potential to increase the quantum yields of other fluorophores.

We report a time-resolved propagating spin wave spectroscopy for Fe19Ni81 film. We show that the amplitude of the spin-wave packet depends on the direction of magnetization and that its phase can be controlled by the polarity of pulsed magnetic field for the excitation. The nonreciprocal emission of spin-wave packet can be utilized for the binary spin-wave input into the spin-wave logic circuit.

This paper proposes a simple technique for minimizing computational effort when modelling practical problems which typically involve several non-linear soil materials with different plasticity parameters and joint elements. The technique is applicable to analyses performed using the pseudo-viscoplastic algorithm for solving non-linear problems. The applicability of the analysis is then evaluated by comparing the authors’ calculated results with published field observations. The paper demonstrates that significant computational savings can be achieved by optimizing the viscoplasticity parameters. It is also demonstrated that the method of analysis adopted provides encouraging agreement with observed field behaviour.

125 I-labeled ( t rifluoromethyl)phenyl d iazirinyl a cetogenin, [ 125 I]TDA, a photoaffinity labeling probe of acetogenin, photo-cross-links to the ND1 subunit of bovine heart mitochondrial NADH–ubiquinone oxidoreductase (complex I) with high specificity [ M. Murai, A. Ishihara, T. Nishioka, T. Yagi, and H. Miyoshi, (2007) The ND1 subunit constructs the inhibitor binding domain in bovine heart mitochondrial complex I, Biochemistry 46 6409–6416.]. To identify the binding site of [ 125 I]TDA in the ND1 subunit, we carried out limited proteolysis of the subunit cross-linked by [ 125 I]TDA using various proteases and carefully analyzed the fragmentation patterns. Our results revealed that the cross-linked residue is located within the region of the 4th to 5th transmembrane helices (Val144–Glu192) of the subunit. It is worth noting that an excess amount of short-chain ubiquinones such as ubiquinone-2 (Q 2 ) and 2-azido-Q 2 suppressed the cross-linking by [ 125 I]TDA in a concentration-dependent way. Although the question of whether the binding sites for ubiquinone and different inhibitors in complex I are identical remains to be answered, the present study provided, for the first time, direct evidence that an inhibitor (acetogenin) and ubiquinone competitively bind to the enzyme. Considering the present results along with earlier photoaffinity labeling studies, we propose that not all inhibitors acting at the terminal electron transfer step of complex I necessarily bind to the ubiquinone binding site itself.

Quantum phase modulation is achieved in a metallic nanoring with a $\mathrm{FeNi}∕\mathrm{Cu}∕\mathrm{FeNi}$ (ferromagnet/normal-metal/ferromagnet) layer. Both frequency and amplitude of Aharonov-Bohm oscillation are found to be modified with respect to the magnetization configurations, indicating that the phase modulation originates from the spin-orbit scattering induced by the magnetization of the ferromagnets. Such phase modulation is ``crossover'' phenomena between mesoscopic magnetism and microscopic quantum interference effects, which provides fundamental knowledge upon quantum spin transport.

This paper describes the formulation of a 6-noded non-linear joint element based on elasto-viscoplasticity and examines the stability criteria for the elements using a simple Euker time-marching scheme. The validity of the stability criteria is examined for a number of simple cases where numerical and analytical results can be compared. It is found that the stability criteria provide good results for all cases examined.

A magnetic-field sensor with a high sensitivity of 38 pT/Hz was demonstrated. By utilizing a spin-wave differential circuit (SWDC) using two yttrium iron garnet (YIG) films, the temperature sensitivity was suppressed, and the thermal stability of the phase of the spin waves was −0.0095° K−1, which is three orders of magnitude better than a simple YIG-based sensor, ∼20° K−1. The SWDC architecture opens the way to design YIG-based magnonic devices.

Antivortex creation in a cross-shaped wire was demonstrated by using magnetoresistance and magnetic force microscopy measurements. The magnetization process was stochastic and exhibited a wide variety of magnetoresistance curves. By developing a conventional method, we have achieved electrical determination criteria to distinguish antivortex creation from many other magnetization states. The electrical criteria provide a simple method without large-scale apparatus and promote further experiments such as spin-current driven antivortex dynamics.

A bioartificial tubule device was applied for the treatment of 10 acute renal failure and multiple organ failure patients by Humes et al. A bioartificial kidney for chronic renal failure patients, however, has never been applied. In order to develop a bioartificial kidney for preventing and treating long-term complications of maintenance dialysis patients, we have to overcome difficulties such as antithrombogenic issue of hemofilters and development of long functioning tubule devices in the context of economical and easy treatment. Continuous hemofilters should modify with an antithrombogenic material on the inner surfaces of membranes to get more hemocompatible characteristics. We are developing an antithrombogenic continuous hemofilter coating with methacryloyloxyethyl phosphorylcholine polymer which will mimic phospholipid layers of human cell membrane on the inner surface of a hemofilter. The transportability of H2O, Na+, and glucose of bioartificial tubule devices using polysulfone hollow fiber modules and porcine proximal tubular epithelial cells LLC-PK1 were evaluated using two kinds of circuits of different medium inside and outside of the cell-attached hollow fiber membrane. Transport of H2O, Na+, and glucose were significantly increased when 2.5 g/dL of albumin was added, and plateaued on the eight day and then decreased thereafter until the 13th day. Transfection of a specific gene into human tubular epithelial cells might be required to keep contact inhibition in order to maintain a confluent monolayer for longer duration.

In this work, the authors report giant magnetoresistance (GMR) and the differential conductance anomalies observed in ferromagnetic nano-contacting wire, which have never been observed in non-magnetic one.

The reduction of size in magnetic materials gives rise to new effects with great potential for spin-based applications. For example, the giant magnetoresistance (GMR) effect observed in nanometer-sized ferromagnetic contacts (nanocontact MR) is thought to be promising for future magnetoresistive sensors; the nanocontact MR is far larger than the normal GMR. Theoretically, it was predicted that the giant MR in nanocontact is the scattering of ballistic electrons. It is then an important issue to clarify the origin of the MR experimentally. In this work, we present detailed nanocontact MR in the conductance-quantization regime where the electron transport is definitely ballistic.

We report a propagating spin wave spectroscopy for a magnetostatic backward volume spin wave in a metallic Fe19Ni81 film. We show that the mutual-inductance between two independent antennas detects a small but clear propagation signal of backward volume spin waves. All experimental data are consistent with the time-domain propagating spin-wave spectroscopy. The control of propagating backward spin wave enables to realize the miniaturize spin-wave circuit.

Strong motion records from the Southern Hyogo earthquake of January 17, 1995, are overviewed. The discussion is focused on (1) the characteristic of near field records including the predominant direction of motion versus the fault strike and their spectral characteristic, and (2) the orientation error of seismometers and ground motion amplification at borehole array stations. Two numerical techniques for seismic response analysis of ground are applied for the array stations. The one is the frequency-dependent equi-linearized technique for the frequency domain analysis, and the other is the effective stress-based liquefaction analysis method. The numerical calculations are compared with the records at four borehole array stations.

We have developed a system of laser-pump and synchrotron radiation probe microdiffraction to investigate the phase-change process on a nanosecond time scale of Ge2Sb2Te5 film embedded in multi-layer structures, which corresponds to real optical recording media. The measurements were achieved by combining (i) the pump-laser system with a pulse width of 300 ps, (ii) a highly brilliant focused microbeam with wide peak-energy width (ΔE∕E ~ 2%) made by focusing helical undulator radiation without monochromatization, and (iii) a precise sample rotation stage to make repetitive measurements. We successfully detected a very weak time-resolved diffraction signal by using this system from 100-nm-thick Ge2Sb2Te5 phase-change layers. This enabled us to find the dependence of the crystal-amorphous phase change process of the Ge2Sb2Te5 layers on laser power.

Spin-wave logic operation in a ferromagnetic thin film was investigated by using a three-antenna device. Binary output 1/0 signals were realized with the constructive and destructive spin-wave interference signals. It was found that the configuration of the RF antenna determines the phase of the input spin wave, which provides a control method of logic operation in spin-wave devices.

A single vortex-core switching induced by current injection into a ferromagnetic disk is detected in real time using a three-terminal device with the tunneling magnetoresistance junction. The real time observation reveals that the electrical core switching is completed within a few 100 ps. It is also found that the core switching takes place at the specific positions inside the disk.

The applied-voltage( V ) dependence of current( I ) passing ferromagnetic Ni quantum wires was investigated with holding a conductance-quantized state. Observed I – V exhibits three-types behaviors: I / V is almost identical up to 50 mV, or increases or decreases with V . The result suggests current-induced reconfiguration of magnetic structures around the quantum wires.

Microwave-assisted recording on a 500-Gbpsi-class perpendicular medium was experimentally demonstrated at room temperature. Magnetization reversal under a radio-frequency magnetic field was measured by an electrically shorted coplanar waveguide, which enabled us to evaluate the change in the medium's ferromagnetic resonance spectrum. A frequency-dependent reduction in the switching field was clearly observed in response to a microwave impulse 50 ns in duration. A significant reduction of up to 30% in the coercive field was achieved by applying a microwave impulse with an amplitude of 25 dBm and a frequency of 15 GHz.

Ferromagnetic resonance (FMR) spectroscopy of granular Co-Cr-Pt films has been studied by means of a vector network analyzer. Though the granular Co-Cr-Pt films have weak magnetic susceptibility, the structural optimization of a coplanar waveguide (CPW) enables the measurement of the weak FMR signal of granular Co-Cr-Pt films, which are a promising medium for magnetic recording. The observed FMR spectra are consistent with the Kittel formula. The optimization of the CPW is well established by our simple model, providing a method to explore the basic magnetic properties of a granular medium.

Spin wave attenuation in the layered left perpendicularFeNi/Ptright perpendicular(6)/FeNi thin films was investigated by the time-domain electrical measurement. The spin-wave waveform was detected with an asymmetric coplanar strip transmission line, as an induced voltage flowing into a fast oscilloscope. We report that the amplitude of a spin-wave packet was systematically changed by controlling the thickness of a platinum layer, up to a maximum change of 50%. The virtues of spin wave, ultrafast propagation velocity and non-reciprocal emission, are preserved in this manner. This means that the Pt layer can manipulate an arbitral power-level of spin-wave input signal (reliable attenuator).

A single vortex-core switching in a ferromagnetic disk is detected in real time by using a three-terminal device with the tunneling magnetoresistance junction. We show that the device works as a vortex core memory cell, where reading and writing can be done in an all-electrical way: binary data corresponding to the core direction can be read out electrically as the amplitude of the output, while the data can be written electrically by applying a pulsed current.

We measured the shot noise in the CoFeB/MgO/CoFeB-based magnetic tunneling junctions with a high tunneling magnetoresistance ratio (over 200% at 3 K). Although the Fano factor in the anti-parallel configuration is close to unity, it is observed to be typically 0.91\pm0.01 in the parallel configuration. It indicates the sub-Poissonian process of the electron tunneling in the parallel configuration due to the relevance of the spin-dependent coherent transport in the low bias regime., Comment: 3 pages, 3 figures

Here, we synthesized fluorescent DNA probes labeled with two perylene derivatives for the detection of a three-base deletion mutant. One such probe discriminated the three-base deletion mutant from the wild-type sequence by exciplex emission, and the deletion mutant was identifiable even by the naked eye.

The electron transport through the CoFeB/MgO/CoFeB-based magnetic tunneling junction (MTJ) was studied by the shot noise measurement. The obtained Fano factor to characterize the shot noise is very close to unity, indicating the full shot noise, namely, the shot noise in the Schottky limit, both in the parallel and antiparallel magnetization configurations. This means the Poissonian process of the electron tunneling and the absence of the electron–electron correlation in the low bias regime. The shot noise measurements will be a good guideline to make up tunneling criteria for designing MTJ-based spin devices.