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Current-driven domain wall motion from pinning sites in nanostrips with perpendicular magnetic anisotropy is studied by using micromagnetic simulations, supported by a one-dimensional model of wall dynamics. The threshold current density of perpendicular anisotropy strips is much smaller than that of in-plane anisotropy strips, and is almost independent of the pinning potential strength. This results from the narrower domain wall width, smaller hard-axis anisotropy, and the larger ratio of the depinning field and hard-axis anisotropy. In the one-dimensional model with a zero damping constant, the threshold current density is found to be about 0.72 of the intrinsic threshold current density for a perfect strip in a strong pinning regime that corresponds to strips with perpendicular magnetic anisotropy. The fact that the threshold current density from the pinning sites is smaller than the intrinsic current density is because the effective field, equivalent to the pinning potential, enhances a breakdown in the pinning site. Moreover, in the strong pinning regime, an opposite-direction depinning hardly ever occurs after current pulse is turned off. These features of strips with perpendicular magnetic anisotropy are attractive for magnetic random access memories where the domain wall should be moved stably between the pinning sites with the small current pulse. [ABSTRACT FROM AUTHOR]

Studies the growth process in the initial stage of growth of germanium films on silicon substrate surfaces by GeH[sub4] source molecular beam epitaxy. Details on the experiment; Results of the study; Conclusions.

Presents a study which measured the structural properties of sputtered CoCrPt samples by x-ray diffraction, small-angle x-ray scattering (SAXS), x-ray absorption fine structure, and transmission electron microscope. Characteristics of the samples; Measurement of the crystal orientation of samples; Method used in measuring SAXS; Clarification of the discontinuous change in SAXS and x-ray absorption near-edge structure range.

Presents a study which examined the relationship between growth processes and strain relaxation in Si[sub1-x]Ge[x] films grown on (100)Si-(2x1) surfaces by gas source molecular beam epitaxy. Experimental procedures; Results of the study; Conclusions.

Current driven domain wall motion in nanostrips with perpendicular magnetic anisotropy was analyzed by using micromagnetic simulation. The threshold current density of perpendicular anisotropy strips in adiabatic approximation was much smaller than that of in-plane anisotropy strips, and it reduced with thickness reduction. The differences originate from the differences in domain wall width and hard-axis anisotropy. Also, the threshold current density of perpendicular anisotropy strips required to depin from a pinning site was quite small although the threshold field of the strips was sufficiently large relative to those of in-plane anisotropy strips. [ABSTRACT FROM AUTHOR]

The critical current density required for current-induced domain wall motion (Jc) was reduced by decreasing the magnetization (Ms) of the free layer film of a U-shaped pattern for a domain wall motion memory. The Ms was decreased by adding the nonmagnetic elements Ta and Cu to NiFe films. The Jc of the U-shaped patterns with NiFe–Ta and –Cu decreased as the proportion of Ta and Cu in the NiFe increased. The relations between Ms and Jc were examined and it was found that Jc decreased monotonically from 1.2×1012 to 0.8×1012 A/m2 as Ms decreased from 1.0 to 0.6 T regardless of what other materials were used. It is considered that the decrease in Ms caused a decrease in the hard axis anisotropy of the pattern, and the Jc decreased as predicted by a one-dimensional model. [ABSTRACT FROM AUTHOR]

An outbreak of enterohaemorrhagic Escherichia coli O157 occurred in multiple prefectures of Japan in November 2009. We conducted two case–control studies with trace-back and trace-forward investigations to determine the source. The case definition was met by 21 individuals; 14 (66.7%) were hospitalised, but no haemolytic uraemic syndrome, acute encephalopathy or deaths occurred. Median age was 23 (range 12–48) years and 14 cases were male (66.7%). No significant associations with food were found in a case–control study by local public health centres, but our matched case–control study using Internet surveys found that beef hanging tender (or hanger steak), derived from the diaphragm of the cattle, was significantly associated with illness (odds ratio = 15.77; 95% confidence interval, 2.00–124.11). Pulsed-field gel electrophoresis analysis of isolates from patients and the suspected food showed five different patterns: two in faecal and food samples, and another three in patient faecal samples only, although there were epidemiological links to the meat consumed at the restaurants. Trace-back investigation implicated a common food processing company from outside Japan. Examination of the logistics of the meat processing company suggested that contamination did not occur in Japan. We concluded that the source of the outbreak was imported hanging tender. This investigation revealed that Internet surveys could be useful for outbreak investigations. [ABSTRACT FROM PUBLISHER]

We study current-induced magnetization switching properties of a magnetic tunnel junction with junction diameter of 19 nm and resistance-area product of 6 Ωμm2 in the nanosecond regime with and without in-plane magnetic field. At zero field, for both parallel (P)-to-anti-parallel (AP) and AP-to-P switchings, the probability of switching PSW approaches unity with the increase of pulse voltage duration τP. However, under in-plane magnetic field, PSW for P-to-AP switching starts to saturate at a value lower than unity with increasing τP, while AP-to-P switching remains the same as in the absence of in-plane magnetic field. This in-plane field dependence of PSW can be partially explained by the influence of electric-field modulation of magnetic anisotropy. [ABSTRACT FROM AUTHOR]

The spin transfer torque is essential for electrical magnetization switching. When a magnetic domain wall is driven by an electric current through an adiabatic spin torque, the theory predicts a threshold current even for a perfect wire without any extrinsic pinning. The experimental confirmation of this 'intrinsic pinning', however, has long been missing. Here, we give evidence that this intrinsic pinning determines the threshold, and thus that the adiabatic spin torque dominates the domain wall motion in a perpendicularly magnetized Co/Ni nanowire. The intrinsic nature manifests itself both in the field-independent threshold current and in the presence of its minimum on tuning the wire width. The demonstrated domain wall motion purely due to the adiabatic spin torque will serve to achieve robust operation and low energy consumption in spintronic devices. [ABSTRACT FROM AUTHOR]

The coordination of small molecules and ions at the sixth position of ferric myoglobins (Mb) from the heart muscle of two species of shark, Lamna ditropis (LD) and Prionace glauca (PG), was studied in frozen solution by electron paramagnetic resonance (EPR) and electron-nuclear double resonance (ENDOR) spectroscopy. The results were compared with those of horse heart Mb (EQMb). From our preliminary studies of the absorption spectra and partial amino acid sequences of PGMb and LDMb, we expected PGMb to have glutamine (Gln E7) in place of the distal His E7 that is highly conserved in most animals and present in LDMb. Here, we have used proton ENDOR to show that a water molecule coordinates to the ferric ion in both LDMb and PGMb at pH 6.3. The observed proton hyperfine coupling constant of the coordinating water molecule of PGMb is smaller than those of LDMb and EQMb, which suggests weaker coordination of the water molecule in PGMb, consistent with the absent distal His (E7). Coordination of several exogenous ligands at the distal site was examined by EPR. PGMb showed a coordination behavior different from that of LDMb and EQMb for 1-methylimidazole, 4-methylimidazole and SCN−, suggesting that its distal site is less sterically hindered. On the basis of the ENDOR and EPR results, we assigned the distal residues of PGMb and LDMb as Gln and His, respectively. [ABSTRACT FROM AUTHOR]

The nonlinear viscoelastic behaviour of arterial walls subjected to large deformation is studied theoretically and experimentally. It is assumed that the arterial walls are thick-walled cylindrical vessels composed of an incompressible, curvilinearly orthotropic and viscoelastic material. The radial displacement of vessel walls is simplified by superimposing a small time-dependent deformation due to pulse pressure on a large time-independent deformation. The radial and circumferential stresses are expressed as functions of the histories of strains in each direction. The functions are written in terms of a series of multiple integrals involving eight stress-relaxation functions. To determine these functions, experiments of stress relaxation were performed with common carotid and femoral arteries excised from mongrel dogs. For a strain imposition within 1-100 s, stress relaxation is expressed by a power-law function of time. On the basis of the theoretical equations, the vessel diameter and wall stresses are calculated as a function of time by assuming that a sinusoidal intraluminal pressure varying between 80 and 120 mm Hg is applied in the lumen. The creep phenomena are shown to be due to the viscoelasticity of the arterial walls. i.e. the deformation increases with elapsed time during pressure fluctuations. [ABSTRACT FROM AUTHOR]

The dietary effect of 1,3-biseicosapentaenoyl-2-γ-linolenoyl glycerol (STG) on the fatty acid composition of guinea pigs was examined and compared with that of an eicosapentaenoic acid ethyl ester (EPA-F) and of a soybean oil (SBO) diet. In terms of content of plasma lipid, EPA-E had a greater hypolipidemic effect than STG. On the other hand, in terms of EPA incorporation, contents of EPA in liver lipid were almost the same in the STG and EPA-E groups. Considering that the amount of EPA administered in the EPA-E group was almost 1.5 times that of the STG group, FPA may be absorbed more effectively as the glycerol ester than as the ethyl ester in guinea pigs. In all the tissue lipids, the STG group had a higher unsaturation index (UI) than the EPA-E group even though there is a lower UI in the STG diet than the EPA-E diet. These results suggest that greater amounts of desaturase products as a whole were synthesized in the STG group than in the other two groups. The dihomo-γ-linolenic acid/arachidonic acid (DGLA/AA) ratio in plasma total lipids in the STG group was 3.5 times that of SBO group, and the DGLA/AA ratio in the EPA-E group was half that of the SBO group. In liver lipid, the ratios of DGLA/AA and EPA/AA in the STG group were 0.687 and 0.488 (phosphatidylcholine fraction) and 0.237 and 0.752 (phosphatidylethanolamine fraction), respectively. The ratio of DGLA/AA as well as the high EPA/AA ratio obtained in the present study with the STG diet may lead to physiological alterations, including enhanced synthesis of 1-and 3-series eicosanoids. [ABSTRACT FROM AUTHOR]

We have investigated the temperature dependence of the current-induced magnetic domain wall (DW) motion in a perpendicularly magnetized Co/Ni nanowire at various temperatures and with various applied currents. The carrier spin polarization was estimated from the measured domain wall velocity. We found that it decreased more with increasing temperature from 100 K to 530 K than the saturation magnetization did. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

We have investigated the velocity of magnetic domain wall (DW) motion induced by electric currents in a Co/Ni nanowire with a perpendicular magnetic anisotropy. The DW velocity increased as current density increased and the maximum velocity of 60 m/s was observed. Furthermore, the DW velocity was found to be almost independent of external perpendicular magnetic fields in the range of -50 to +50 Oe. The mechanism of the observed field insensitivity of the current induced DW motion is also discussed. [ABSTRACT FROM AUTHOR]

The point contact Andreev reflection technique was employed to estimate the spin polarization of currents in Co/Pt multilayered thin film and Co–Pt alloy film with perpendicular anisotropy. The spin polarization of currents in the Co–Pt alloy film was estimated to be 0.48, while that in Co/Pt multilayered film was 0.56. These results suggest that the spin-polarization of currents in multilayered film is enhanced compared to that in alloy film. [ABSTRACT FROM AUTHOR]

We investigated the relation between critical current of domain wall motion and wire dimension by using perpendicularly magnetized Co/Ni nanowires with different widths and thicknesses. The critical current, Ic, became less than 0.2 mA when w<100 nm, suggesting that magnetic random access memory with domain wall motion can replace conventional embedded memories. In addition, in agreement with theory, the critical current density, jc, decreased as wire width decreased and became much less than 5×107 A/cm2 when w<100 nm. We also performed a micromagnetic simulation and obtained good agreement between the experiment and simulation, although a few discrepancies were found. [ABSTRACT FROM AUTHOR]

We fabricated toggle magnetic random access memories with clad writing lines. First, we evaluated the structures and magnetic properties of sputter-deposited cladding layers. The substrate bias during the deposition affected not only the sidewall coverage, but also the crystallinity and magnetic properties of the cladding. The optimized clad lines reduced the writing current to as low as 50% of that of unclad lines. Moreover, the writing current deviation divided by the average current of magnetic tunnel junction cells with clad lines was as low as that with unclad lines. Using the optimized clad lines, we constructed memory arrays with a large operating margin and reduced switching current. [ABSTRACT FROM AUTHOR]

Presents a study on the structure and saturation induction of CobaltNickelIron (CoNiFe) electroplated films. Function of CoNiFe electroplated films; Details on the experiment; Results and discussion.

Objectives: We performed cochlear implantation (CI) for a deaf child with the severely malformed cochlea. Music therapy likely is a contributing factor to the development for severely hearing impaired children. Cochlear aplasia is considered as a contraindication or very difficult indication for CI . This is likely a case of cochlear aplasia using Sennaroglu Classification. Case: A 5-year-7-month old girl's Newborn Hearing Screening (NHS) was refer. Her ABR, ASSR (MASTER) showed No Response. Preoperative CT findings revealed 'Aplastic Cochlea and Facial nerve anomaly'. We implanted the first CI on 2011, and the second CI on 2013. I inserted a whole medium electrode into her left ear and a whole compressed electrode into her right ear of Med- EL. Her postoperative progress has been encouraging in that her speaking ability as well her speech understanding have steadily improved. As her parents wished for her to sing nursery rhymes, we enrolled her in musical therapy. The Music Therapist at our center performed a family participation type session for about 40x50 mins. once a month. Our therapist used multiple musical instruments in conjunction with a piano and also interacted with her in related activities, for example playing, singing songs and playing musical instruments jointly with her. After a 3-year period, her WTH with CI shows 35dBHL. Her ITMAIS score improved from 1 to 40 (maximum score). Her LittleEARS results increased from 7 to 35 (also maximum score). Upon repeated sessions, her initially monotone singing voice dramatically improved to the point she was able to confidently perform the songs. Auditory-Oral communications improved in various situations. She enrolled into a 1st grade class at a regular elementary school. The music therapy brought not only musical benefits to the child, but also contributed to the development of speech language, phonation as well as her social skills. [ABSTRACT FROM AUTHOR]

We applied multistrained short-period superlattices (SSPSs) and GaP buffer layers to the InP-on-Si heteroepitaxy, in order to suppress the generation of threading dislocations. As a result, it was found that the density of threading dislocations in an InP/SSPSs/GaAs/SSPSs/GaP/Si structure including (InAs)m(GaAs)n SSPSs and (GaAs)i(GaP)j SSPSs was remarkably reduced, compared with that in the InP/GaP/Si structure. Misfit dislocations lying along the <011> directions were observed at heterointerfaces in the InP/SSPSs/GaAs/SSPSs/GaP/Si structure. Therefore, the lattice mismatch strain was stepwise accommodated by the generation of misfit dislocations at the heterointerfaces. From these results, it was clarified that multi-SSPSs are effective for reducing the density of threading dislocations in heteroepitaxy with a large lattice mismatch. © 1996 American Institute of Physics. [ABSTRACT FROM AUTHOR]

An ordered structure with the double periodicity in a <111> direction has been found by in situ reflection high-energy electron diffraction observation in the initial stage of Ge films grown on (100)Si and (811)Si substrate surfaces by GeH4 gas source molecular beam epitaxy. The ordered structure is formed on {111} planes parallel to the side planes of <011> steps on {811} facets of Ge growing islands on both substrates. The formation is observed at substrate temperatures of 300–700 °C and is considered to result from solid phase reactions at the interfaces during growth. [ABSTRACT FROM AUTHOR]

Presents an abstract of a study that investigated the structural properties of CoCrPt samples that have been sputtered at different levesl of sputtering power, which affects magnetic properties.

Objectives: We examined the integration rate into regular schools of children with cochlear implants and considered favorable factors affecting successful integration. Furthermore, We investigated important points in school education of pediatric cochlear implants from my over 150 school visit experiences of children with cochlear implants. Material and Method: We followed with schools that enrolled children under 18 who underwent cochlear implant between 1998 and September 2016 while attending our hearing rehabilitation centre during the same time period. Results and Conclusions: 202 children were of school-age or older with 144 attending regular school. The rate of integration of our children patients with CI was 71.3%. Other than 2015, when more than an average number of children were enrolled in regular kindergarten and nurseries, the rate of integration into regular schools over the last five years has been between 80% and 90%. The main contributors that account for the high rate of inclusion are newborn hearing screening 84.3%, bilateral cochlear implants 82%, early detection of hearing loss due to gene mutation and viral disease, preoperative auditory verbal 98%/oral 72% habilitation using hearing aids, surgery between 1 and 2 years of age 82-86%and the ongoing interaction with the full-time speech-hearing-language therapist at the school for deaf 69% and at our center 97%. Having visited over 150 schools to follow how children after CI have adapted to regular education, a discussion of important aspects in school education to cater to these children follows. [ABSTRACT FROM AUTHOR]

By means of an intracellular glass microelectrode, action potential changes were successfully recorded in situ from the endothelial cells of rat mesenteric lymphatics over the temperature range of 27-40°C. The frequency of action potential and the lymphatic contraction rate correlated well with temperature. [ABSTRACT FROM AUTHOR]