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Very-high Energy (VHE) gamma-ray astroparticle physics is a relatively young field, and observations over the past decade have surprisingly revealed almost two hundred VHE emitters which appear to act as cosmic particle accelerators. These sources are an important component of the Universe, influencing the evolution of stars and galaxies. At the same time, they also act as a probe of physics in the most extreme environments known - such as in supernova explosions, and around or after the merging of black holes and neutron stars. However, the existing experiments have provided exciting glimpses, but often falling short of supplying the full answer. A deeper understanding of the TeV sky requires a significant improvement in sensitivity at TeV energies, a wider energy coverage from tens of GeV to hundreds of TeV and a much better angular and energy resolution with respect to the currently running facilities. The next generation gamma-ray observatory, the Cherenkov Telescope Array Observatory (CTAO), is the answer to this need. In this talk I will present this upcoming observatory from its design to the construction, and its potential science exploitation. CTAO will allow the entire astronomical community to explore a new discovery space that will likely lead to paradigm-changing breakthroughs. In particular, CTA has an unprecedented sensitivity to short (sub-minute) timescale phenomena, placing it as a key instrument in the future of multi-messenger and multi-wavelength time domain astronomy. I will conclude the talk presenting the first scientific results obtained by the LST-1, the prototype of one CTAO telescope type - the Large-Sized Telescope, that is currently under commission., PoS: Proceedings of Science, 395, ISSN:1824-8039, Proceedings of 37th International Cosmic Ray Conference (ICRC2021)

We have investigated the laminar and the turbulent flow in superfluid 4He using a vibrating wire made of thin NbTi (φ 2.5 μm). The wire velocity as a function of applied force has shown a large hysteresis at the first cooling from normal fluid to the superfluid state. But after a couple of increasing and decreasing wire velocity we have found that the hysteresis vanished and the laminar and the turbulent flow are clearly separated at a critical velocity. The wire moving just after the first cooling must be influenced by remnant vortices nucleated through the superfluid transition. The appearance of the laminar flow below the critical velocity suggests that vortex strings on the wire seem to be selected as suitable sizes by a vibrating flow at higher velocities. We also measured the velocity dependence after immersing the wire directly into the superfluid and found that the laminar region expands up to a velocity much higher than the critical velocity observed above. This result indicates that remnant vortices are considerably reduced by the immersing method. © 2005 Springer Science+Business Media, Inc.

We have studied the flow of superfluid 4He generated by a vibrating wire. As the drive force increases, the velocity of the wire grows in the laminar-flow regime, until it suddenly drops at the onset of the turbulent-flow regime. As the drive force decreases, the turbulence disappears at a critical velocity. This result suggests that the vortices on the wire are confined within a finite size, even in turbulence. We have measured the critical velocity of seven vibrating wires, whose resonance frequencies range from 0.5 kHz to 9 kHz, at 1.4 K and found that the critical velocity is almost constant below an oscillation frequency of 2 kHz and increases above this frequency. We have also observed the response of a vibrating wire in superfluid 4He at a low temperature of 30 mK. We find that the resonance frequency jumps upward at the same moment as the entry of the flow to a turbulent state. The frequency jump may be caused by vortex dynamics such as expansion, entanglement, and reconnection occurring in the turbulence. © 2006 American Institute of Physics.

To investigate whether it is possible to control the wetting of ^{4}He crystals on a wall in superfluid, the contact angles of ^{4}He crystals were measured on rough and smooth walls at very low temperatures. A rough wall was prepared in a simple manner in which a commercially available coating agent for car mirrors, which makes the glass surface superhydrophobic, was used to coat a glass plate. The contact angles of ^{4}He crystals were increased by approximately 10^{∘} on the rough wall coated with the agent. Therefore, the increase in the repellency of ^{4}He crystals in superfluid was demonstrated to be possible on a very rough surface. The enhancement of the contact angles and a scanning electron microscopy image of the coated surface both suggest that a Cassie-Baxter state of ^{4}He crystals was realized on the surface; the crystals did not have full contact with the wall, but entrapped superfluid was present beneath the crystals in the hollow parts of the rough wall.

We report the turbulent transition in superfluid 4He generated by a vibrating wire as a function of its thickness. The response of a vibrating wire with a 3 μm diameter in superfluid 4He at 1.2 K reveals a hysteresis at the turbulent transition between an up sweep and a down sweep of driving force, while no hysteresis appears for wires with a thickness larger than 4.7 μm diameter. These results indicate that the 3 μm wire is efficient for reducing the number of vortex lines attached to it. A cover box and slow cooling also prevent vortex lines from attaching to a wire, resulting in a vortex-free vibrating wire. The effective mass of the vortex-free vibrating wire is almost constant in a wide range of velocities up to 400 mm/s; however, the wire density estimated from the resonance frequency is a half of the expected value of wire material, suggesting that a wire mass becomes lighter or a wire diameter becomes larger in the superfluid effectively.

The superconductivity depression mechanisms at x≈1/8 in La2−xBaxCuO4 and Zn substitution in La2−xSrxCuO4 were investigated by Raman scattering. About 80% of low-energy electronic states are two-dimensional at x≈1/8 and form the Fermi arc around (π/2,π/2). The low-energy states are composed of the resonant peak relating to the insulator–metal transition and the polaron states of the B3u phonons. Zn substitution depresses the resonant peak, while the LTT structure depresses the polaron states. The superconductivity is suppressed if one of them is reduced.

内視鏡，注腸など従来の画像診断に加えMRIが診断に有用であったS状結腸子宮内膜症の1例を経験したので報告する．症例は39歳女性で腹痛を主訴に受診．注腸造影でtransverse ridging, 内視鏡では病変部に一致して片側性に顆粒状粘膜，小隆起に囲まれた中に発赤，びらん面を認めた．生検で炎症細胞浸潤をともなう非特異的所見のみであった．12MHz超音波内視鏡で病変部に一致した全層性の高エコー像を認めた．T1強調MRI像で病変部に相当する肥厚した大腸壁内に出血の存在を示唆する高信号を認め，ガドリニウム造影で同部位に造影効果は認められなかった．以上より腫瘍性病変は否定的と考え，S状結腸子宮内膜症と診断．ホルモン療法により腹痛などの臨床症状は軽快.保存的治療の限界，悪性化の危険性などのインフォームド·コンセントを行った上で本人の希望に沿い注意深い観察のもと経過観察を行っている．

[1] Three-dimensional (3-D) distribution of scattering coefficients in the crust beneath northern Miyagi prefecture of northeastern Japan is estimated using an envelope inversion method in order to investigate the short-wavelength inhomogeneous structure that cannot be imaged by conventional travel-time tomography. The inversion revealed two large scattering coefficient zones (LSZs) which are distributed beneath active volcanoes and around the mainshock fault of the 1962 M 6.5 Northern Miyagi earthquake. These LSZs merge in the lower crust, and the characteristic distribution correlates well with the previously reported seismic low-velocity zones, which are perhaps caused by fluids. We inferred that fluids are supplied from the lower crust to the upper crust along the LSZs, resulting in inhomogeneous structures such as localized distribution of fluid-filled cracks. It is expected that this distribution of fluids will cause strain and stress accumulation, affecting seismic activity in this region. INDEX TERMS: 7205 Seismology: Continental crust (1242); 7218 Seismology: Lithosphere and upper mantle; 7230 Seismology: Seismicity and seismotectonics; 8180 Tectonophysics: Tomography. Citation: Asano, Y., K. Obara, J. Nakajima, and A. Hasegawa (2004), Inhomogeneous crustal structure beneath northern Miyagi prefecture, northeastern Japan, imaged by coda envelope inversion: Implication for fluid distribution, Geophys. Res. Lett., 31, L24615, doi:10.1029/2004GL021261.

In-situ characterization of the surface nature and re-crystallization of c-axis YBa/sub 2/Cu/sub 3/O/sub 7-/spl delta// (YBCO) films engineered by Ar ion etching and subsequent annealing has been carried out. Effects of kinetic energy of the Ar ions and annealing conditions have been examined. RHEED and XPS measurements showed that etching with the ion energy above a few hundred eV for longer than 60 sec yielded insulating and amorphous surface layers. Analysis of XPS core signals revealed a deviation of surface composition toward a Y-rich one with an increase of the product of [ion flux] /spl times/ [ion energy] /spl times/ [etching time], whereas thickness and degree of reduction of the amorphous layer were dominated by the kinetic energy of the Ar ions: the higher ion energy resulted in a thicker and less reduced layer. For the amorphous layer created by the 500 eV-beam etching, oxidation-annealing at 630/spl deg/C for 1h is sufficient to convert it into a metallic 123 structure. For the surfaces treated by the 1 keV etching, an insulating feature was conserved even after the annealing of 710/spl deg/C, 1 h or 660/spl deg/C, 3 h. These results mean that the higher energy etching and the shorter subsequent process are desired to properly fabricate barrier layers for the interface-engineered sandwich type of junctions.

Epitaxial c -axis EuBa 2 Cu 3 O 7−x (EBCO) films were deposited on R-Al 2 O 3 substrates with CeO 2 buffer layers of various thicknesses. EBCO films of different thicknesses were prepared at various substrate temperatures ( T s ), and their R s values at 50 GHz and J c (at 77.3 K) were measured. A 0.5-μm-thick EBCO film deposited on a 30-nm-thick CeO 2 buffer layer at T s =650 ° C showed a minimum R s value of 6.6 m Ω and a J c value of 0.99×10 6 A/cm 2 at 77.3 K. As-sputtered EBCO films of the same thickness deposited on MgO showed an R s value of about 2 m Ω (extrapolation value) at 77.3 K. The R s value of EBCO on R-Al 2 O 3 ⧹CeO 2 was about three-times larger than that on MgO substrates. This result is due to the large asymmetry of R-Al 2 O 3 .

Detection of shallow slow earthquakes offers insight into the near-trench part of the subduction interface, an important region in the development of great earthquake ruptures and tsunami generation. Ocean-bottom monitoring of offshore seismicity off southern Kyushu, Japan, recorded a complete episode of low-frequency tremor, lasting for 1 month, that was associated with very-low-frequency earthquake (VLFE) activity in the shallow plate interface. The shallow tremor episode exhibited two migration modes reminiscent of deep tremor down-dip of the seismogenic zone in some other subduction zones: a large-scale slower propagation mode and a rapid reversal mode. These similarities in migration properties and the association with VLFEs strongly suggest that both the shallow and deep tremor and VLFE may be triggered by the migration of episodic slow slip events.

The influence of environment on fatigue crack growth behaviour was investigated both in nearly lamellar and in duplex titanium aluminides, and the hydrogen evolution kinetics was analysed by thermal desorption spectroscopy. The tensile strength of the duplex material decreases in the order of the extent of the water molecule content in the environment: the strength in vacuum is the highest, and decreases in the order of laboratory air and finally in water. In the case of the lamellar material, the fatigue crack growth rate in dry air is higher in the R-C crack plane orientation than that in the L-C crack plane orientation. The crack growth rate becomes higher when the crack grows as the lamellae tear. However, in the case of the duplex material, the crack growth rate in the R-C crack plane orientation is smaller in the low AK (ΔK eff ) region. When cathodic charging is applied, the fatigue crack growth rate becomes higher than in dry air, particularly in the higher stress intensity factor range. The hydrogen evolution rate is increased by cathodic charging, with lower temperature peaks and higher ones. The peaks at lower temperatures are correlated with the decomposition of hydrides and de-training of hydrogen from microstructural imperfections such as microvoids. As-received materials also show an evolution peak at a higher temperature, and the evolution rate is almost independent of cathodic charging. In addition, the evolution rate at a high temperature (above 800 °C) is increased by cathodic charging. The hydrogen is considered to have an important role on fatigue crack growth acceleration.

Background and Objectives Mutations detected in 161 weak D samples from Caucasians have been classified into 16 types. Because flow cytometry using monoclonal anti-D antibodies (mAbs) has shown that weak D red cells display type-specific antigen density, these mutations in transmembranous regions have been assigned weak D phenotypes. The present study attempts to confirm or refute this assignment. Materials and Methods We amplified DNA from four Japanese weak D samples using the polymerase chain reaction (PCR), and directly sequenced the amplified DNA. Using site-directed mutagenesis, we constructed three vectors expressing mutant RHDs – G212C, V270G (weak D type 1) and G358A (type 2) – in K562 cells. The expression of RhD antigens was examined by flow cytometry using mAbs. Results A new mutation resulting in a conversion at amino acid residue 212 (Gly to Cys) was detected in a Japanese weak D sample. K562 cells transduced with mutant RhD cDNA reacted weakly in a type-specific manner with mAbs. Conclusions The mutations – G212C (new weak D type), V270G (weak D type 1) and G358A (type 2) – in transmembranous regions had obvious effects on the D epitopes recognized by mAbs. The results of this study provide direct evidence that these mutations can account for weak D phenotypes.

Summary Temporal variation of the scatterer distribution has been detected around the focal area of an M6.1 earthquake, northeastern Japan, by applying semblance analysis to seismic array data. The variation was found in slant-stacked waveforms of two explosions detonated just above the focal area one month before and two months after the M6.1 earthquake. According to geodetic observations, a pressure source that might be a magma reservoir exists beneath this region and its location changed during the observation period. Slant-stacked waveforms are slightly different for the two explosions. The difference suggests that a scatterer contributing to the coda part is shifted towards the east and to greater depths only after three months. In this region, seismic and volcanic activity was very active during the interval between the two explosions. The volcanic activity of Mt Iwate just north of the M6.1 earthquake, which started several months beforehand, continued during this period. It may be considered that scatterer change relates to seismic and/or volcanic activity in the studied area.

We discuss the single scattering model by using seismic array data. By analyzing observed seismic array records, we found that coda energy level for slant-stacked record is smaller than that for single station record as expected from the single scattering model. The energy level of slant-stacked waveform is dependent on stacking direction. The energy level variation for different slant-stacking directions suggests that horizontally aligned scatterers predominate over vertical ones. The present analysis is probably useful to detect scattering anisotropy.

A change of electronic structure and chemical bond nature of high pressure synthesized (Cu,Tl)Ba/sub 2/Ca/sub 2/Cu/sub 3/O/sub 9-/spl delta// [(Cu,Tl)-1223] and TlBa/sub 2/Ca/sub 2/Cu/sub 3/O/sub 9-/spl delta// [Tl-1223] with reduction-annealing, which leads to a significant rise of their superconducting transition temperature T/sub c/ above 130 K, has been investigated by in-situ photoemission spectroscopy. Their intrinsic surface nature has been achieved by fracturing in vacuum. In (Cu,Tl)-1223, a Fermi edge is observed for the first time. Trivalent Tl and heavily over-doped states of Cu-O clusters are dominant in as-grown specimens of both systems. The annealing resulted in remarkable shifts of photoemission spectra of Ba and Tl core levels towards higher binding energy with an increase of the annealing temperature, which means a selective oxygen-depletion around their charge-reservoirs and a decrease of valency of Tl. In contrast, there are quite little shape-changes and movements in valence band spectra and core signals of Cu and O. These results reveal that, in the high temperature-treated specimens, major portions of the electrons left should be absorbed into the cations in their charge reservoir, which consequently should cause a much more moderate change of the hole-concentration of the CuO/sub 2/ planes. It suggests that the utilization of this charge-redistribution mechanism in over-doped specimens should be an advantageous way to optimize the electronic structure of the 1223 phases for high T/sub c/.

An outgassing rate is measured using a waveguide module during a long pulse r.f. injection at 3.7 GHz in order to operate a lower hybrid current drive (LHCD) antenna in steady state. The waveguide module consists of four sub-waveguides which are made of dispersion-strengthened copper and copper-plated stainless steel with cooling channels to control its working temperature between 100 and 500 °C. The waveguide module shows the high power capability of power density up to 200 MW m −2 after short term conditioning. A low outgassing rate of about 2 × 10 −7 Pa m 3 s −2 m −2 is obtained during r.f. injection up to 150 MW m −2 at a working temperature of T =300 °C after 450 °C baking. Long pulse r.f. injection is effective for reduction of the outgassing by about 1/100. Outgassing during r.f. injection depends on the working temperature but is independent of the r.f. power density after sufficient conditioning. The calculation code taking desorption, adsorption and diffusion processes into account can show time behavior of outgassing in the waveguide module. A quasi-constant outgassing of about 10 −7 Pa m 3 s −1 m −2 is observed at a power density of 150 MW m −2 in 1800 s injection while keeping a saturated temperature at the center of the module below 120 °C by using water cooling. The outgassing properties obtained indicate that steady state operation of an LHCD antenna is feasible without a large pumping system.

Este artigo mostra as principais dificuldades computacionais que limitam a incorporação de Ambientes Virtuais Tridimensionais (AVA 3D) no componente educacional. O projeto utiliza a proposta open-source para o desenvolvimento de ambiente 3D, a partir do OpenSimulator. Conclui-se que a limitação computacional, embora complexa, pode ser superada e os quatro experimentos realizados decorrentes do projeto AVA 3D mostram que o espaço virtual tridimensional pode se aplicar com êxito à proposta acadêmica de cursos a distância, uma vez que os acadêmicos que estudam pela Web acessam naturalmente suas salas virtuais, no caso deste projeto, o Moodle.

Mechanical behavior of a knife‐edge‐type metal‐seal flange system was examined on the variations of the displacement between the flanges and reaction forces of the tightening bolts during load steps such as tightening the bolts, setting up a transverse weight load on the flange surface and 300 °C baking and cool down. These were compared with a thermo‐elasto‐plastic finite element method structural analysis. Good agreement was obtained for both the flange deformation and reaction forces of the bolts and copper gasket between experimental and analytical results. Effects of the transverse load by a dummy weight mounted at the flange surface on the changes of reaction force of the bolts and on gasket deformation were considered to be negligibly small in the view of vacuum seal characteristics. The application of Inconel Belleville spring washers between bolt heads and flange surface was confirmed to be quite effective for the suppression of the bolt force looseness and gasket relaxation due to cyclic heating and cooling of the knife‐edge‐type metal‐seal flange system.

The adsorptive collection of the molybdenum (VI) complex of 2-(2′-thiazolylazo)-p-cresok (TAC), coupled with the catalytic current of the adsorbed complex, yield an ultrasensitive voltammetric procedure for the determination of molybdenum. Optimal experimental conditions were found with the use of a stirred acetate buffer (pH 2.9) supporting electrolyte, a TAC concetration of 1.0 × 10−5 M, and a concentration of 0.1 M potassium nitrate. In addition, a preconcentration potential of −0.13 V (vs. Ag/AgCl), equilibrium time of 30 seconds, and an anodic scan rate of 200 mV/s from −0. 93 to −0. 20 was used. A catalytic effect was observed when nitrate was present. The response was found to be linear over a concentration range of 0.0 to12.0 μg L−1 Mo (VI). For a preconcentration time of 3 minutes, the detection limit was found to be 11 pM. Possible interferences by anions and other trace metals were investigated. The interference by copper may be masked by CDTA, and sequential determination with molybdenum is possible. The merits of the procedure are demonstrated in the analysis of sea and mineral water.

Pedunculopontine tegmental nucleus (PPN) contributes to the control muscle tone by modulating the activities of pontomedullary reticulospinal systems during wakefulness and rapid eye movement (REM) sleep. The PPN receives GABAergic projection from the substantia nigra pars reticulata (SNr), an output nucleus of the basal ganglia. Here we examined how GABAergic SNr-PPN projection controls the activity of the pontomedullary reticulospinal tract that constitutes muscle tone inhibitory system. Intracellular recording was made from 121 motoneurons in the lumbosacral segments in decerebrate cats (n=14). Short train pulses of stimuli (3 pulses with 5 ms intervals, 10-40 mA) applied to the PPN, where cholinergic neurons were densely distributed, evoked eye movements toward to the contralateral direction and bilaterally suppressed extensor muscle activities. The identical PPN stimulation induced IPSPs, which had a peak latency of 40-50 ms with a duration of 40-50 ms, in extensor and flexor motoneurons. The late-latency IPSPs were mediated by chloride ions. Microinjection of atropine sulfate (20 mM, 0.25 ml) into the pontine reticular formation (PRF) reduced the amplitude of the IPSPs. Although conditioning stimuli applied to the SNr (40-60 mA and 100 Hz) alone did not induce any postsynaptic effects on motoneurons, it reduced the amplitude of the PPN-induced IPSPs. Subsequent injection of bicuculline (5 mM, 0.25 ml) into the PPN blocked the SNr effects. Microinjections of NMDA (5 mM, 0.25 ml) and muscimol (5 mM, 0.25 ml) into the SNr reduced and increased the amplitude of the PPN-induced IPSPs, respectively. These results suggest that GABAergic basal ganglia output controls postural muscle tone by modulating the activity of cholinergic PPN neurons which activate the muscle tone inhibitory system. The SNr-PPN projection may contribute to not only control of muscle tone during movements in wakefulness but also modulation of muscular atonia of REM sleep. Dysfunction of the SNr-PPN projection may therefore be involved in sleep disturbances in basal ganglia disorders.

Temperature dependence of complex admittance and growth process of surface oxide were investigated. New dispersion relations of dielectric constant and conductance were found in the inital state of the oxidation of niobium super-fine particles. The frequency dependence of dielectric constant (∝ capacitance) showed a resonant type characteristics with a very low resonant frequency ω 0 ∼1 kHz σ ( ω ) steeply decreased above the resonant frequency. These characteristics strongly depended on the product of oxygen pressure and time. These new dispersion relations suggest the existence of any kind of ordered structure on the surface before a thick insulator is formed. In the initial stage of oxidation, a phase transition was found at 158 K. The temperature dependences of capacitance and conductance below 158 K suggest the growth of metallic region in the surface oxide.

A quadrupole mass spectrometer (QMS) with a specially designed analyzing head which was movable in a dynamic vacuum system was fabricated and the performance was tested. The head comprises a collimator and an airtight casing containing a rf tuning and its detection circuit. The rf circuit is tuned by supplying variable frequency of the rf voltage since the resonance frequency depends weakly on environmental temperature. This QMS can be obtain a normal mass spectrum for a mass range 1–50 amu even when the vessel is baked to 150 °C. The measured pressure rise of Ar is 1.08×10−5 Pa at a distance of 125 mm from the effusing nozzle of argon gas with a flow rate of 1.9×10−5 Pa m3 s−1, which is two times as large as the calculated value.A quadrupole mass spectrometer (QMS) with a specially designed analyzing head which was movable in a dynamic vacuum system was fabricated and the performance was tested. The head comprises a collimator and an airtight casing containing a rf tuning and its detection circuit. The rf circuit is tuned by supplying variable frequency of the rf voltage since the resonance frequency depends weakly on environmental temperature. This QMS can be obtain a normal mass spectrum for a mass range 1–50 amu even when the vessel is baked to 150 °C. The measured pressure rise of Ar is 1.08×10−5 Pa at a distance of 125 mm from the effusing nozzle of argon gas with a flow rate of 1.9×10−5 Pa m3 s−1, which is two times as large as the calculated value.

The transition to turbulence in the boundary flow of superfluid 4He is investigated using a vortex-free vibrating wire. At high wire vibration velocities, we found that stable alternating flow around the wire enters a turbulent phase triggered by free vortex rings. Numerical simulations of vortex dynamics demonstrate that vortex rings can attach to the surface of an oscillating obstacle and expand unstably due to the boundary flow of the superfluid, forming turbulence. Experimental investigations indicate that the turbulent phase continues even after stopping the injection of vortex rings, which is also confirmed by the simulations.

Recent lower hybrid current drive (LHCD), and heating (LHH) experiments on JT-60 are reported. The current drive product of neRpIRF approximately 12.5*1019 m-2 MA was achieved at the LH power of approximately 4.5 MW, and the CD efficiency, the energy confinement, the global power balance and the heat load on divertor plates were investigated in high power LHCD plasmas. Nearly steady state H-mode discharges were found during LHCD with two different frequency injections. Sawtooth suppression in NB heated plasmas by LHCD have shown an improvement in confinement near the plasma center. Parametric instabilities in LH heating experiments were significantly reduced by increasing the plasma current, and the stored energy increased linearly with heating power of up to approximately 9 MW at ne approximately 7*1019 m-3 and Ip=2.75 MA. Parametric instabilities near the plasma edge in the ion heating regime were also reduced in peaked density plasmas produced by pellet injection and LH waves increased the central plasma pressure at ne(0) > 1.4*1020 m-3.

The transition to turbulence in the boundary flow of superfluid 4He is investigated using a vortex-free vibrating wire. At high wire vibration velocities, we found that stable alternating flow around the wire enters a turbulent phase triggered by free vortex rings. Numerical simulations of vortex dynamics demonstrate that vortex rings can attach to the surface of an oscillating obstacle and expand unstably due to the boundary flow of the superfluid, forming turbulence. Experimental investigations indicate that the turbulent phase continues even after stopping the injection of vortex rings, which is also confirmed by the simulations.

We have investigated the turbulence transition of the superfluid 4He flow generated by a vibrating wire. For a 1.2-kHz vibrating wire, we observed intermittent switchings between laminar and turbulent flows. The switching rate decreases with increasing temperature above 100 mK, until no occurrence of the switchings at 350 mK. For a 2.4-kHz vibrating wire, we find that the switching rate is much lower than that of the 1.2-kHz vibrating wire even at low temperatures. This result indicates that a mechanism causing the switchings is influenced by the temperature and the oscillation frequency of the superfluid flow. © Springer Science+Business Media, LLC 2007.

The jawbone is replete with a vestige of odontogenesis. The overall consensus is that intraosseous remnants of the enamel organ and dental lamina are the only histogenetic option for central epithelial odontogenic tumors. Curiously, incipient tumors or possible precursor conditions of residual odontogenic epithelium have rarely been reported in the literature.We microscopically evaluated 39,660 biopsy samples to determine the presence of a tumor-like odontogenic epithelial nodule in the maxilla and mandible.Seven intraosseous specimens that associated with a focal proliferation of odontogenic epithelium were retrieved. Six hamartomatous processes showed four different morphologic patterns comparable with the tumor nests comprising ameloblastoma (n = 1), squamous odontogenic tumor (n=1), calcifying epithelial odontogenic tumor (n=2) and calcifying cystic odontogenic tumor (n=2). Among six lesions, four were the intrafollicular development. The remaining case of interest was multiple hyperplastic clear rests of Malassez in association with an impacted tooth.Although it is impossible to predict the fate of these microscopic structures of hamartomatous character, the present case series indicates that any of the dormant embryonic residues of odontogenic epithelium can return to an active state, capable of non-reactive, probably neoplastic proliferation of pathological significance.

The electronic states in La2−xSrxCuO4 are systematically investigated by Raman scattering, infrared‐ultraviolet reflection spectroscopy, and electric resistivity. A narrow quasi‐particle band is created at EF and sharply grows up by collecting the density of states from the high energy region at 1–1.5 eV as temperature decreases near the insulator‐metal transition. The relaxation time of conducting carriers is limited by the quasi‐particle band width near the insulator‐metal transition, but it drastically increases in the overdoped phase. The quasi‐particle band gives the anomalous electronic properties.The electronic states in La2−xSrxCuO4 are systematically investigated by Raman scattering, infrared‐ultraviolet reflection spectroscopy, and electric resistivity. A narrow quasi‐particle band is created at EF and sharply grows up by collecting the density of states from the high energy region at 1–1.5 eV as temperature decreases near the insulator‐metal transition. The relaxation time of conducting carriers is limited by the quasi‐particle band width near the insulator‐metal transition, but it drastically increases in the overdoped phase. The quasi‐particle band gives the anomalous electronic properties.

Orthogonal frequency division multiplexing (OFDM) has gained a much attention for wireless communication technology in recent years. OFDM signal has a large peak-to-average power ratio (PAPR), which brings disadvantages like a degradation of the BER performance and the radiation of the out-of-hand spectrum. To reduce the large PAPR, using complementary sequences as input to generate an OFDM symbol is one of effective techniques. A coding scheme of complementary sequences taking the advantage of the code redundancy in nonlinear OFDM systems is proposed, and computer simulation has been preformed. The results show that the out-of-band spectrum is suppressed and the BER performance is also improved compared with uncoded signal, using complementary sequences is an effective method for spectrum suppression and BER improvement in nonlinear OFDM systems.

We have investigated the laminar and the turbulent flow in superfluid 4He using a vibrating wire made from a thin NbTi wire (φ 2.5 μm). We measured vibrating velocity of the wire as a function of driving force at 1.4 K and found that the laminar and the turbulent flow around the wire are clearly separated at a critical velocity. This phenomenon suggests that expansion of vortices attached on the wire causes the turbulence and those sizes are limited to an order of microns even in the turbulent flow. This limitation is considered due to tangle and reconnection of the vortices by oscillating flow. The critical velocity varies with frequency of the oscillating flow and the vortices seem to be confined closely at high frequencies. We also found a stable state of the vortices thickly attached on the wire by controlling cool down through the superfluid transition. © 2005 Elsevier Ltd. All rights reserved.

As a part of our project, we have developed a HiperLAN2 based OFDM system which works with a 70 GHz front end. The main purpose of this paper is to study optimum parameters in order to realize a new OFDM based system that enables at least more than 100 Mbit/s. By using the actual measured propagation data, basic robustness comparison in the multipath environment for both OFDM and single carrier PSK system is discussed to show how OFDM is suitable for the 70 GHz multipath environment in order to pursue high data rate transmission. For the conclusion of this paper, an example of parameter optimization is performed under a 70 GHz indoor multipath environment.

The ATX (asynchronous transmission and exchange) network utilizing current narrowband digital leased lines (up to 6 Mb/s) is proposed. Architecture enhancements in the proposed ATX system are considered. The use of ATM (asynchronous transfer mode) technology in the ATX is evaluated for the following applications: economical and small-size ATM switch architecture suitable for the narrowband environment, traffic control to achieve high efficiency in line utilization in cases where the number of statistically multiplexed channels is relatively small, and adaptation to accommodate existing conventional PBXs and terminals without change. Results of evaluations are reported. >

[1] Strong scattering sources were detected in the upper mantle beneath central Japan from seismic data recorded by the high-sensitivity seismograph network (Hi-net). Anomalous seismograms, consisting of many strong later phases whose amplitudes did not decay significantly with time, were observed from an intermediate-depth earthquake. A comparison of those anomalous seismograms with others generated by other deep earthquakes shows that major scattering sources may exist predominately in the upper mantle, not in the crust. Three possible candidates have been considered as the sources of scattering in the upper mantle including magma conduits, the previous collision zone and slab melting. Although seismic waves may be scattered strongly from each potential candidate, a region associate with slab melting might be more suitable for generating the anomalous seismogram due to the existence of abundant melting spots within the subducted Philippine Sea slab that is extremely young and hot beneath central Japan. INDEX TERMS: 0669 Electromagnetics: Scattering and diffraction; 7218 Seismology: Lithosphere and upper mantle; 7230 Seismology:Seismicityandseismotectonics.Citation: Lin, C.-H., M. Ando, N. Fujii, K. Yamaoka, K. Tadokoro, A.-S. Jin, K. Obara, and M. Ishida, Anomalous seismograms generated by an intermediate-depth earthquake: Unusual scattering sources in the upper mantle of central Japan, Geophys. Res. Lett., 30(11), 1586, doi:10.1029/2002GL016837, 2003.

An efficient killer-defect control method using a reliable high throughput scanning electron microscope and automatic defect classification (ADC) is described. The concept of ADC system-class is used to facilitate recipe set-up (defect imageless tuning). Experiments demonstrated that the performance of this method exceeds that specified by the International Technology Roadmap for Semiconductors. This method is applicable to both application-specific IC and system-on-chip production lines.

Mutations detected in 161 weak D samples from Caucasians have been classified into 16 types. Because flow cytometry using monoclonal anti-D antibodies (mAbs) has shown that weak D red cells display type-specific antigen density, these mutations in transmembranous regions have been assigned weak D phenotypes. The present study attempts to confirm or refute this assignment.We amplified DNA from four Japanese weak D samples using the polymerase chain reaction (PCR), and directly sequenced the amplified DNA. Using site-directed mutagenesis, we constructed three vectors expressing mutant RHDs-- G212C, V270G (weak D type 1) and G358A (type 2)--in K562 cells. The expression of RhD antigens was examined by flow cytometry using mAbs.A new mutation resulting in a conversion at amino acid residue 212 (Gly to Cys) was detected in a Japanese weak D sample. K562 cells transduced with mutant RhD cDNA reacted weakly in a type-specific manner with mAbs.The mutations--G212C (new weak D type), V270G (weak D type 1) and G358A (type 2)-- in transmembranous regions had obvious effects on the D epitopes recognized by mAbs. The results of this study provide direct evidence that these mutations can account for weak D phenotypes.

In 26 patients with lacunar syndromes, emergence of new lacunar infarctions were identified within 13 days from onset by diffusion-weighted magnetic resonance images. The identified lacunar infarctions were repeatedly imaged using fluid-attenuated inversion recovery (FLAIR) sequence up to 600 days from onset. On FLAIR images taken by 23 days from onset, lacunar infarctions showed homogeneous hyperintensity. On the later FLAIR images beyond 25 days from onset they were observed as heterogeneously hyperintense lesions in half of the patients. In the other patients, lacunar infarctions were observed as hypointense areas with a hyperintense rim beyond 41 days from onset, which indicates cystic transformation with surrounding gliosis. These FLAIR images of lacunar infarction differ from those of dilated perivascular space which is observed as an area of simple hypointensity.

We determined the nucleotide sequences of two regions in the A+T-rich region of mitochondrial DNA (mtDNA) in the siI and siII types of D. simulans, the maII type of D. mauritiana, and D. sechellia. The sequences were aligned with those of the corresponding regions of siIII of D. simulans and maI of D. mauritiana, D. melanogaster, and D. yakuba. The type I and type II elements and the T-stretches were detected in all eight of the mtDNA types compared, indicating that the three elements are essential in the A+T-rich region of this species subgroup. The alignment revealed several short repetitive sequences and relatively large deletions in the central portions of the region. In the highly conserved sequence elements in the type II elements, the substitution rates were not uniform among lineages and acceleration in the substitution rate might have been due to loss of functional constraint in the stem–loop-forming sequences predicted in the type II elements. Patterns of nucleotide substitutions observed in the A+T-rich region were further compared with those in the coding regions and in the intergenic regions of mtDNA. Substitutions between A and T were particularly repressed in the highly conserved sequence elements and in the intergenic regions compared with those in the A+T-rich region excluding the highly conserved sequence elements and in the fourfold degenerate sites in the coding regions. The functional and structural characteristics of the A+T-rich region that might be involved in this substitutional bias are discussed.

Mycobacterial heat shock protein (hsp) 65 has more than 50% sequence homology with human hsp60 and immune responses against mycobacterial hsp65 may cross-react with human hsp60 and could cause autoimmune diseases including inflammatory bowel diseases (IBD). Since the colonic mucosa is a main inflammatory site in IBD, mucosal immunity to hsp65 may be more important for the mucosal inflammation than systemic immunity to hsp65. We inoculated plasmid DNA (pDNA) encoding mycobacterial hsp65 (pACB-hsp 65) into the colon of Wistar rats and evaluated the mucosal humoral immune response and the effect of these immune responses on the colonic mucosa. Four weeks after pDNA inoculation, significantly elevated titers of hsp65-specific IgA antibody were seen in fecal extracts of rats immunized intra-colonic mucosa with pACB-hsp65 (40 +/- 9 U/ml), whereas the fecal IgA antibody titers of rats inoculated intradermal with pACB-hsp65 did not arise (8 +/- 5 U/ml). Colonic inoculation of pACB-hsp65 induced systemic and mucosal immune responses to hsp65. However, macroscopic and histological examinations of the colonic mucosa inoculated with pACB-hsp65 showed no evidence of mucosal damage. These results suggested that the mucosal immunity to hsp65 on the colonic mucosa may not play a crucial role in the induction of colonic mucosal inflammation as was seen in IBD.