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Magneto-optical Faraday devices, such as optical isolators, require a structure to apply a magnetic field to the incorporated magneto-optical material. The application of a magnetic field hinders the miniaturization and integration of these devices. Nanogranular films show Faraday rotation angles up to 40 times larger than Bi-YIG in the optical communication band (1,550 nm). Nanogranular films are submicron-to several-micrometer-thick and contribute to the miniaturization and integration of optical devices. Here, we introduce (Co-Pt)–(CaF2) nanogranular films exhibiting a magnetic-field-free magneto-optical Faraday effect, which are Co3Pt alloy that are hard magnets with residual magnetization. These nanogranular films exhibit the Faraday effect without requiring a magnetic field owing to their residual magnetization.

Nanogranular films consisting of a complex of nanometer-sized magnetic granules and a dielectric insulator matrix exhibit a large Faraday rotation. In this study, the dielectric tensor of the nanogranular films with high refractive silicon nitride matrix are measured, and the effect of refractive index of the matrix and magnetic granules on the dielectric tensor is analyzed. Compared with the fluoride (low refractive index) matrix nanogranular films, the Faraday rotation angle is approximately two times higher in the nanogranular FeCo-SiN film, which exhibits a high refractive index effect on the Faraday rotation angle.

Ultra-high resistive and anisotropic soft magnetic films for gigahertz applications are desirable to demonstrate the really practical films. Here we present a study of novel nanogranular films fabricated by tandem-sputtering deposition. Their electromagnetic properties and nanostructure have also been discussed. These films consisted of nanocrystallized CoPd alloy-granules and CaF2 matrix, and a specimen having a composition of (Co0.69Pd0.31)52–(Ca0.31F0.69)48 exhibited distinct in-plane uniaxial anisotropy after uniaxial field annealing with granule growth. Its complex permeability spectra have a ferromagnetic resonance frequency extending to the Super-High-Frequency band due to its higher anisotropy field, and its frequency response was quite well reproduced by a numerical calculation based on the Landau–Lifshitz–Gilbert equation. Furthermore, it was clarified that the CaF2-based nanogranular film exhibits a hundredfold higher electrical resistivity than conventional oxide or nitride-based films. Higher resistivity enables the film thickness to achieve a margin exceeding threefold against eddy current loss. The greater resistivity of nanogranular films is attributed to the wide energy bandgap and superior crystallinity of CaF2 matrix.

Highlights • Magnetoelectric effect in the nanogranular FeCo-MgF films has been investigated. • Magnetoelectric effect and dielectric relaxation are confirmed at frequencies over 10 MHz. • The inter-spacing of granules and the relaxation time decrease with increasing magnetic metal concentration. • The magnetoelectric effect reaches a maximum at a relaxation frequency., The magnetoelectric effect is a key issue for material science and is particularly significant in the high frequency band, where it is indispensable in industrial applications. Here, we present for the first time, a study of the high frequency tunneling magneto-dielectric (TMD) effect in nanogranular FeCo-MgF films, consisting of nanometer-sized magnetic FeCo granules dispersed in an MgF insulator matrix. Dielectric relaxation and the TMD effect are confirmed at frequencies over 10 MHz. The frequency dependence of dielectric relaxation is described by the Debye-Fröhlich model, taking relaxation time dispersion into account, which reflects variations in the nature of the microstructure, such as granule size, and the inter-spacing between the granules that affect the dielectric response. The TMD effect reaches a maximum at a frequency that is equivalent to the inverse of the relaxation time. The frequency where the peak TMD effect is observed varies between 12 MHz and 220 MHz, depending on the concentration of magnetic metal in the nanogranular films. The inter-spacing of the films decreases with increasing magnetic metal concentration, in accordance with the relaxation time. These results indicate that dielectric relaxation is controlled by changing the nanostructure, using the deposition conditions. A prospective application of these nanogranular films is in tunable impedance devices for next-generation mobile communication systems, at frequencies over 1 GHz, where capacitance is controlled using the applied magnetic field.

sensor5) can be operated at room temperature; however, they are comparatively large in scale, making it difficult to integrate them in a sensor array. Highly sensitive magnetic field thin film sensors operating at room temperature are useful for biomedical applications or nondestructive evaluation. Thus, development of a thin film sensor to measure biomagnetic signals at room temperature was the aim of this study. As previously reported, a coplanar line-type thin film sensor with a ceramic substrate (r = 115) to enhance sensitivity of phase change was developed 6) and successfully used to obtain magnetocardiograms (MCGs) at multiple points7). The ceramic substrate with high permittivity decreases the wave length of the carrier, the phase dramatically changing when a small field is applied. However the sensor is bulky and cannot be integrated. In the present study, we developed a thin film integrated sensor including magnetic thin film, dielectric film and conductive film. These structure can be easily developed for array sensors with the same characteristics. The goal of this study was to obtain a sensor with good characteristics (phase change > 100 degree/Oe, gain > -40 dB) for obtaining magnetocardiograms 7) .

We have undertaken a detailed field, petrological, geochronological, and modeling study of Esan volcanic complex, northern Japan, in order to establish its eruptive history over the past 50,000 yr. The Esan volcanic complex includes seven lava domes, which are endogenous domes developed without basal edifices. Each dome was produced by intermediate to silicic magmas with 57–67 wt% SiO 2 that were erupted in magnitude 4–5 eruptions. Five explosively erupted pyroclastic units cover the aprons of these lava domes. The spatial and temporal relationships of the domes and the pyroclastic units have been determined in order to constrain the eruptive sequence of the Esan volcanic complex. A simple elastic model, assuming a hydraulic connection state, was utilized to study variations in long-term magma discharge at the Esan volcanic complex, which have been attributed to changes in magma storage conditions. The stepwise change in magma discharge with time, which is 4.2–5.3 × 10 4 m 3 /yr, is interpreted to reflect a change between magma chamber radius ( R c ) and magma depth ( H c ) caused by an upward migration of magma. Assuming a continuous input of magma from a deep source at a constant supply rate, the magma storage system that existed during the early stage of the Esan volcanic complex has been renewed, which will result in a shorter recurrence interval between eruptions rather than a long period of dormancy (22,400 yr). Given this finding, and the fact that the most recent eruption occurred 9000 yr ago, there is currently a risk of a large eruption at the Esan volcanic complex.

For the sensor probe of high frequency magnetic field in GHz region, films were prepared by liquid phase epitaxy technique and ferromagnetic resonances were investigated in high frequency region. Magneto-optical (MO) effect of magnetic garnet was utilized for the imaging sensor of the magnetic field distribution. However, for the application to the characterization of high frequency magnetic field in the GHz frequency region, usual MO measurements are difficult to detect the magnetic filed as the decreasing of the permeability of magnetic garnet. Magnetic resonance is an effective way to induce magnetic moment and enhance the magnetooptical effect in high frequency region of GHz order. In order to understand the possibility of magnetic field sensor of high frequency in detail, far-infrared magnetic resonances were measured at the high frequencies up to 315 GHz in pulsed high magnetic field. Taking account into sensitivity of MO signals and magnetic resonance intensities, magnetooptical method using a garnet film is effective at the frequencies below 100 GHz.

ホッケ（AG），スケトウダラ（WP），両者混合すり身（AG＋WP）に0～2/3倍量の水と0～3％卵白粉末（AP）を加え3％ NaCl (w/w）と共に塩ずりした．25℃で予備加熱後，90℃, 30分加熱して加熱ゲルを得て，その物性値と総タンパク質（すり身＋卵白）濃度（C）の関係を検討した．（1） 坐りゲルは，WPと（AG＋WP）から形成されたが，AGからは形成されなかった．（2） 加熱ゲルのCとBSとの間の指数関係（BS＝k・Cn, k, n＝定数）は，AGから調製されたものはAPの添加によって変化しなかったが，一方，WPおよび（WP＋AG）からの場合は，APの添加によって明らかに異なった．（3） 加熱ゲルの破断凹み（bs）の最大値は，加熱ゲルの原料すり身の魚種によって異なるが，加熱ゲルのbsの最大値はAPを加えてもほぼ同じだった．以上の結果から，すり身と卵白タンパク質から調製される加熱ゲル形成は，坐りを伴った加熱ゲルと伴わない加熱ゲルとでは異なる機序で進行することが示唆される．

ホッケ，スケトウダラ，およびそれらの混合すり身に0～3％の血漿（P）または卵白（A）粉末を加えた肉糊を25℃で15時間にわたって予備加熱し，さらに90℃で30分加熱して二段加熱ゲルを調製した．加熱ゲルの破断強度（BS）と破断凹み（bs）をレオメーターで測定し，ゲル剛性（Gs＝BS/bs）を求め，比較した．0.5-1.0％のPとAを加えた加熱ゲル形成に対する影響は以下の点で類似していた．（1）同量のPとAを加えた加熱ゲルのBSとbsの最大値はほとんど同じだった．（2）予備加熱時間に依存して起こる二段加熱ゲルのBSとbsの時間的推移はPおよびAを加えても同じになった．（3）BSとGsの関係図で比べると，PとAを加えた加熱ゲルの物性上の特徴は，無添加の加熱ゲルのそれと類似していた．一方，3.0％のPまたはAを加えた加熱ゲルの物性の最大値および物性上の特徴はやや異なっていた．

等級の異なる 10 種のスケトウダラ冷凍すり身に加水して調製した加熱ゲルの破断強度（BS），破断凹み，及びゲル剛性（Gs）とタンパク質（P）濃度の関係を解析した。そして，① BS と Gs は P 濃度に伴って指数関数的に増大，②加水しない加熱ゲルの BS と Gs の最大値はすり身の等級が上位の方が高く，③ BS vs Gs を図示すると，10 種のすり身から得た加熱ゲルの両値の間に強い正の相関があった。これらの結果は，その BS と Gs のレベルと P 濃度依存性から見積る加熱ゲル形成能が，冷凍すり身の品質要因の一として有用であることを示す。

冷凍すり身の構成成分が二段加熱ゲルの物性に及ぼす影響について検討した。①すり身に水分または糖を添加すると加熱ゲルの破断強度（BS）とゲル剛性（Gs）の最大値は減少した。②タンパク質濃度が同じ加熱ゲル間では糖の増加（6.1→24.5%）により Gs 最大値は変わらずに BS 最大値は減少した。③タンパク質と水分濃度が同じ加熱ゲル間では糖の減少（7.7→3.7%）により BS と Gs の最大値は変らなかった。以上の結果は二段加熱ゲルの物性をその構成成分組成の調節で設定できることを示す。

Ly49Q is expressed on peripheral mouse plasmacytoid dendritic cells (pDC). Immature Ly49Q-negative pDC precursors acquire Ly49Q in the bone marrow and then migrate into the periphery. While searching for molecules that regulate pDC maturation, we found that type I interferon (IFN) inhibited Ly49Q acquisition in vitro. Infections that induce type I IFN production by cells other than pDC (a condition mimicked by poly(I:C) injection in vivo) increase the prevalence of Ly49Q(-) pDC in the bone marrow and peripheral lymphoid organs in wild-type but not IFN-alpha/beta receptor knockout BALB/c mice. Moreover, in vivo exposure to type I IFN causes some Ly49Q(-), but not Ly49Q(+), pDC to convert to conventional DC, defined as B220(-) CD11c(+) CD11b(+) cells. These data suggest that type I IFN regulates pDC development and affects their distribution in the body.

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The authors propose a magnetic actuator for use as a navigation system for capsule endoscopes. The actuator is composed of a capsule dummy, a permanent magnet inside the capsule, and an external spiral structure. The device rotates and propels wirelessly when exposed to an external rotational magnetic field. In this study we measured the effect of the spiral shape on the velocity and thrust force properties. According to our experimental results, the actuator obtained a maximum velocity and thrust force when the spiral angle was set at 45 degrees, the number of spirals was set at 4, and the spiral-height was set at 1-㎜f. We also conducted a motion test in the large intestine of a pig placed on a 30 degrees slope. The actuator passed through a 700 ㎜ length of the intestine in about 300 s. The device also managed to travel up and down the 30 degrees slope with no difficulty whatsoever. Our results demonstrate the great potential of this actuator for use as a navigation system for capsule endoscopes.

This paper describes a cantilevered actuator driven by magnetostriction in a low magnetic field. The dimensions of the two-layer actuator were 1 mm × 5 mm, and amorphous FeSiB was used as the positive magnetostrictive material. The theoretical formulas for the amount of displacement and force of the actuator were obtained. In the experiment, a nonmagnetic polyimide film material and a negative magnetostrictive Ni film material were used as the substrates. The change in the characteristics of the actuator caused by changing the substrate was examined with theoretical formulas and experiments. It is shown that the actuator with Ni as the substrate was designed to obtain the largest displacement and the largest force. © 2007 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.

We tried to control the magnetic anisotropy of a high-frequency carrier-type magnetic field sensor by the shape of the magnetic film instead of induced anisotropy. We confirmed that the impedance of the sensor could be changed by applying a magnetic field. In addition, we tried to control the magnetic anisotropy with magnetostatic energy. We show that the properties of the sensor can be controlled by designing the shape of the magnetic film. © 2007 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.

We propose a new system for sensing the positions of up to five wireless magnetic markers using phase detection. It consists of five resonated markers, a driving coil, and pickup coils. Slim LC resonated markers were fabricated and a detector was formed by connecting high-speed AD converters. The system has a position accuracy of around 1 mm, and can be used for highly accurate position sensing without magnetic shielding, because it is free from earth field noise. We tracked fingertips using five resonated markers.

Somatic DNA methylation patterns are determined in part by the de novo methylation that occurs after early embryonic demethylation. Oct-3/4, a pluripotency gene, is unmethylated in the blastocyst, but undergoes de novo methylation and silencing during gastrulation. Here we show that the transcriptional repressor GCNF recruits DNA methyltransferase to the Oct-3/4 promoter and facilitates its methylation. Although acetylation of histone H3 at lysine 9 (K9) and/or 14 (K14) and methylation of H3 at lysine 4 (K4) decrease during this period, as do Oct-3/4 transcript levels, H3K9 and H3K27 methylation levels remain constant, indicating that DNA methylation does not require repressive histone modifications. We found that GCNF interacts directly with Dnmt3 molecule(s) and verified that this interaction induces the methylation of the Oct-3/4 promoter. Our finding suggests a model in which differentiation-induced GCNF recruits de novo DNA methyltransferase and facilitates the silencing of a pluripotency gene.

Cdc7 kinase, conserved through evolution, is known to be essential for mitotic DNA replication. The role of Cdc7 in meiotic recombination was suggested in Saccharomyces cerevisiae , but its precise role has not been addressed. Here, we report that Hsk1, the Cdc7-related kinase in Schizosaccharomyces pombe , plays a crucial role during meiosis. In a hsk1 temperature-sensitive strain ( hsk1-89 ), meiosis is arrested with one nucleus state before meiosis I in most of the cells and meiotic recombination frequency is reduced by one order of magnitude, whereas premeiotic DNA replication is delayed but is apparently completed. Strikingly, formation of meiotic dsDNA breaks (DSBs) are largely impaired in the mutant, and Hsk1 kinase activity is essential for these processes. Deletion of all three checkpoint kinases, namely Cds1, Chk1, and Mek1, does not restore DSB formation, meiosis, or Cdc2 activation, which is suppressed in hsk1-89 , suggesting that these aberrations are not caused by known checkpoint pathways but that Hsk1 may regulate DSB formation and meiosis. Whereas transcriptional induction of some rec genes and horsetail movement are normal, chromatin remodeling at ade6-M26 , a recombination hotspot, which is prerequisite for subsequent DSB formation at this locus, is not observed in hsk1-89 . These results indicate unique and essential roles of Hsk1 kinase in the initiation of meiotic recombination and meiosis.

Numb and its homologue, Numb-like (Numbl), play important roles in mammalian development, but their role in embryonic development of lower vertebrates remains unknown. We cloned a zebrafish numb homologue (znumb) by searching database. znumb shows approximately 60% identity with mammalian Numb orthologs. Interstingly, znumb lacks two specific sequence motifs unique to Numbl orthologs. However, chromosomal localization of znumb gene revealed colinearity with genes located around mouse and human Numbl genes. Furthermore, multi-species comparisons of conserved phosphotyrosine-binding (PTB) domain sequences in Numb and Numbl proteins suggest that znumb is more closely related to Numbl than Numb. znumb mRNA was expressed in a wide variety of zebrafish adult tissues. Overexpression of znumb in embryos resulted in an absence, or reversal, of the normal leftward shift of the developing heart tube. Furthermore, no or bi-lateral transcripts of lefty2 were observed in znumb-expressing embryos, suggesting that the Notch signaling was essential for left–right field formation and maintenance in zebrafish, and that znumb perturbed this process through down-regulation of endogenous Notch signaling.

Rab11 family interacting protein 4 (Rab11-FIP4) was initially identified in humans as an Rab11-binding protein, but its biological function has remained unknown. We cloned the zebrafish orthologue of Rab11-FIP4 (zRab11-FIP4) and analyzed its function in vivo by using antisense morpholino. zRab11-FIP4 was expressed as 2 alternative transcripts, i.e., the longer A-form predominantly expressed in neural tissues and the shorter B-form expressed ubiquitously; and in situ hybridization revealed that the A-form was the dominant form. In the developing retina, zRab11-FIP4 was expressed in progenitors throughout the retina at early stages; and then, along with the differentiation, the expression became gradually restricted to the ganglion cell layer and ciliary marginal zone. zRab11-FIP4A knockdown embryos exhibited eye phenotypes similar to those of the shh mutant, such as a small eye with impaired cell proliferation and the delay in cell-cycle exit and differentiation of retinal progenitors. The lack of induction of p57kip2 and enhanced expression of cyclin D1 were observed in the morphant retina. Importantly, the delay in cell-cycle exit was rescued by ectopic expression of either p57Kip2 or dominant-negative PKA, suggesting that Rab11-FIP4A plays pivotal roles in retinal development by regulating Shh signaling and a mechanism acting in parallel with Shh signaling in the control of cell-cycle exit.

We propose a new system for sensing the position of a wireless magnetic marker using phase detection. It consists of a resonating wireless magnetic marker, a driving coil, and pickup coils. A slim LC resonating marker (1.2 mm in diameter and 10 mm long) was fabricated and a deteactor was formed by connecting high-speed AD converters. The system has a position accuracy of around 1 mm, and it can be used for highly accurate position sensing without magnetic shielding, because it is free from earth field noise.

We designed high-frequency-carrier type thin-film sensors to obtain high impedance change by controlling the annealing temperature, and investigated the relationships between the noise level, magnetic permeability, and domain structure. Meander-type sensor elements were fabricated, and a magnetic field resolution of 3.4 x 10-8 Oe/Hz1/2 at 501 kHz was obtained.

Recently, the use of VoIP, which is a voice communication service based on an IP network, has been spreading rapidly. However, the quality of service of VoIP has not currently reached the quality of service of a conventional circuit-switched network due to the technical features of an IP network. For IP networks to replace conventional circuit-switched networks in the future, various types of present-day problems must be resolved. Therefore, the authors propose a method of performing admission control for VoIP call setup requests to assure voice quality according to management of the number of VoIP sessions based on the assumption that the quality of a fixed capacity is assured according to VoIP priority control in addition to the packet-level quality provisions of ITU-T Recommendation Y.1541. They also show experimental results concerning the VoIP quality of service measurement indices required by this proposal, the effectiveness of admission control, and the monitor for the number of VoIP sessions and discuss contributions to standardization for promoting more widespread use of the VoIP quality assurance method. © 2006 Wiley Periodicals, Inc. Electron Comm Jpn Pt 1, 90(2): 12–22, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecja.20331