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For more than four decades after the introduction of cv. Italia (Vitis vinifera L.) in Brazil, several somatic mutations in the genome of cv. Italia and its somatic mutants gave rise to phenotypes which generated at least five new cultivars of fine table grapes. Since no molecular marker proved to be effective in discriminating cv. Italia (V. vinifera L.) and its coloured mutants (Rubi, Benitaka, Brasil, Black Star), primers for the long terminal repeat (LTR) sequences were developed to analyse Inter Retrotransposon Amplified Polymorphism (IRAP) and Retrotransposon-Microsatellite Amplified Polymorphism (REMAP), and investigate how the coloured cultivars derived from clonal propagations of somatic mutations are genetically structured. Primers for LTR sequences of IRAP and REMAP markers were edited from grape sequence databases available at a GenBank. Twenty-four primers, denominated DKS001–DKS024, were edited. Three hundred and forty-nine DNA segments were amplified by individual DKS primers and DKS/ISSR (Inter Simple Sequence Repeats) primer combinations, at an average of 13.96 amplicons per primer pair. High genetic divergence between the five cultivars was inferred from polymorphism in retrotransposons IRAP and REMAP. The analysis of polymorphism of IRAP and REMAP retrotransposons was crucial to show that clonal propagation of somatic mutations may lead towards the formation of genetically divergent cultivars by the formation of genetically structured vineyards and show the mixture of genomes within each cultivar.
In this study, direct numerical simulation of the flow around a rotating sphere at high Mach and low Reynolds numbers is conducted to investigate the effects of rotation rate and Mach number upon aerodynamic force coefficients and wake structures. The simulation is carried out by solving the three-dimensional compressible Navier–Stokes equations. A free-stream Reynolds number (based on the free-stream velocity, density and viscosity coefficient and the diameter of the sphere) is set to be between 100 and 300, the free-stream Mach number is set to be between 0.2 and 2.0, and the dimensionless rotation rate defined by the ratio of the free-stream and surface velocities above the equator is set between 0.0 and 1.0. Thus, we have clarified the following points: (1) as free-stream Mach number increased, the increment of the lift coefficient due to rotation was reduced; (2) under subsonic conditions, the drag coefficient increased with increase of the rotation rate, whereas under supersonic conditions, the increment of the drag coefficient was reduced with increasing Mach number; and (3) the mode of the wake structure becomes low-Reynolds-number-like as the Mach number is increased.
The magnetic field geometry in the central regions of two dark clouds has been mapped by measuring the polarization at 2.2 μm of background stars and of stars embedded in the clouds. The observations were done with the Kyoto polarimeter on the Agematsu 1m IR telescope in December 1984 for Heiles Cloud 2 in the Taurus dark cloud complex, and on the UKIRT 3.8m in May and July 1985 for the ρ Ophiuchus dark cloud core. The main results are:
i)Most of the stars in both regions show polarization and their maxima are 2.7% in Heiles Cloud 2 and 7.6% in ρ Oph, respectively. There are similar positive relations between polarization degree and extinct ion Av's.
ii)The distribution of position angles for Heiles Cloud 2 shows a single mode at about 50° and that for ρ Oph shows a bimode, at about 50° and 150°.
iii)The magnetic fields, as delineated by the infrared polarization, appear perpendicular to the flattened elongations of the molecular clouds.
Extensive reflection nebulae have been discovered around GGD27 IRS and around W75N IRS by mapping the infrared polarization in the K band.
It was found that the infrared radiation from both objects is extended at λ = 2.2 μm, by using the Agematsu 1-m, the UH 2.2-m, and the UKIR 3.8-m telescopes. We have carried out polarization mapping with the Kyoto polarimeter on the UKIRT in August 1985.
We are currently conducting three kinds of IR surveys of star forming regions (SFRs) in order to seek for very low-mass young stellar populations. First is a deep JHKs-bands (simultaneous) survey with the SIRIUS camera on the IRSF 1.4m or the UH 2.2m telescopes. Second is a very deep JHKs survey with the CISCO IR camera on the Subaru 8.2m telescope. Third is a high resolution companion search around nearby YSOs with the CIAO adaptive optics coronagraph IR camera on the Subaru. In this contribution, we describe our SIRIUS camera and present preliminary results of the ongoing surveys with this new instrument.
The transport properties of doped and undoped, high quality, plasma-assisted molecular beam epitaxy grown tin dioxide (SnO2) thin films are reviewed. Intentional doping can vary the SnO2 resistivity over more than seven orders of magnitude from a transparent conducting oxide-like conductivity up to the semi-insulating range. A region of high unintentional n-type conductivity was identified in the substrate interface region and had to be accounted for. Sb was a well-behaved shallow donor up to the regime of conducting oxides. In and Ga were too deep acceptors to achieve p-type conductivity but were suitable to render SnO2 semi-insulating. While the surface accumulation layer strongly influenced contact properties, its conductance was negligible. The methodology used here for studying the transport can also be applied to other semiconducting oxides.
Disaster preparedness is one of the national priorities. In Japan, disaster medicine is defined as a part of the national medical plan initiated by Ministry of Health, Welfare and Labor. The Japan Medical Association is the largest professional physicians' group in Japan, and has contributed to all kinds of disaster relief work regionally and nation-wide for years. Based on past successes, the Japan Medical Association proposes a new disaster action plan named Japan Medical Association Team (JMAT). The primary mission of JMAT is to deploy to the disaster scene requested and work for disaster relief. JMAT covers the acute to sub-acute phase of disaster response, and also collaborate with other agencies. In the preparation and mitigation phases, the Japan Medical Association work for establishing mutual disaster aid partnerships, disaster plans, networks with other agencies, team building, disaster medicine training and education, etc. In Japan, the Disaster Medical Assistant Team (DMAT) has been established based on the experience of the 1995 Kobe Earthquake, when lots of preventable trauma deaths occurred because of delayed medical response. The mission of DMAT is to deploy to the scene immediately and triage/transfer the most serious disaster victims outside the scene for advanced medical care. DMAT covers the first 48 hours of disaster response phase, and then JMAT takes charge of the work. JMAT will also respond to chemical, biological, radiological and nuclear disasters, and international humanitarian work. The present issues of establishing JMAT are 1.training and education for Japan Medical Association members, 2.establising cooperation with other agencies, and 3.having presence at the Central Disaster Committee, Cabinet Office, Government of Japan.
An amorphous silicon TFT particularly suited for the full color liquid crystal display driver has been developed and reported here. Various fundamental factors involved in the a-Si TFT, such as the effects of structure, materials, and the method of fabrications were reviewed and investigated in terms of the field effect mobility, the threshold voltage and the reliabilities. An inverted-staggered TFT structure was employed for the purpose wherein the interface states between two layers was successfully lowered by employing the successive deposition procedures of SiNx gate insulator on the a-Si layer. Proper ohmic contacts and the blocking of hole injections were accomplished by forming a n+ layer between the a-Si layer and the source/drain metal electrodes which consists of a double layer of Al/MoSi2 in order to prevent the aluminum diffusion into the a-Si layer during the 300°C heat treatment at the succeeding fabrication processes. The degradation of display images due to the high intensity backlights was minimized by employing a light shielding layer and by making the thickness of a-Si layer 200 Å against the direct sunlight of up to 100,000 luxes. Stable actual performances of TFT for more than 4000 hours at 80 °C were confirmed. The development of a color LCD TV driven by this TFT is also reported.
Dissociation species produced by low-energy electron Irradiation of triethylgallium (TEGa) have been used as a carbon doping source during growth of GaAs by chemical beam epitaxy. Mass spectral analysis shows that TEGa dissociates at electron energies greater than 20 eV, and that the fragmentation pattern of TEGa consists of methyl radicals, ethyl radicals, and gallium compounds. In order to study the doping properties of carbon, carbon-doped GaAs films were grown under several conditions and were characterized by Hall measurements, photoluminecence spectrum, secondary Ion mass spectrometry, and double crystal X-ray diffraction. The hole carrier concentration could be varied up to ∼1020 cm−3, and the doping profile of carbon was well-controlled.
Our experimental results about aperiodic magnetoconductance in narrow n+-GaAs wire are described. These wires are fabricated in an MOCVD grown n+-GaAs film by electron beam lithography and the dry etching technique. It is found that the aperiodic structure arises from the quantum interference which is important in small structures (<1in). The experimental results are compared to the recent theory.
First, we studied the relation between the sp3 bond ratio and the hardness of 100-nm-thick tetrahedral amorphous carbon (ta-C) films deposited by a Filtered Cathodic Arc (FCA) system at different substrate bias voltages. For comparison, sputtered amorphous carbon (a-C) films and Highly Oriented Pyrolytic Graphite (HOPG) were also analyzed. According to the results, ta-C film deposited at a -70 volt substrate bias voltage had high hardness and high sp3 bond ratio of up to 88 GPa and 85%, respectively, whereas those of sputtered a-C were 29 GPa and 28%. Furthermore, we found that the hardness of carbon films, including sputtered a-C and HOPG, increased with increasing sp3 bond ratio. Based on this relation, the chemical bond structures of carbon films are considered to be closely related to their mechanical properties. Secondly, we investigated the relation between sp3 bond ratio and ta-C film thickness, over the range from 1 to 10 nm. The measurements showed that a 2-nm-thick initial layer grown on the surface of CoCrPt magnetic film had low sp3 bond ratios. It is suggested that this reduction in sp3 bond ratio in the initially grown layer seriously degrades the film's performance as a hard disk media overcoat. Further efforts to improve ta-C film processing will be required to improve its mechanical properties.
A high stability electrode technology with TaSiN as a barrier metal was used to fabricate a stacked SBT capacitor array on polySi plugs, and hysteresis characteristics and contact properties of the stacked capacitor were studied.
Migration of protons dissolved in acceptor doped SrZrO3, SrCeO3 and BaCeO3 oxides has been examined under an applied electric potential over a range of temperature from 25 to 220°C. Protons which dissolved in these oxides migrated to the cathode, and they were trapped there when the cathode material had a good ability to getter the migrating hydrogen. The amount of hydrogen accumulated in the cathode could be measured by the ERDA method using a highenergy 4He beam. We measured the amount of hydrogen in the cathode while monitoring the dc current passed through the oxide specimen. The proton transport number was determined from the ratio of the number of hydrogen in the cathode to the total numbers of charge through the specimen. The diffusion coefficient of proton was evaluated using the proton transport number and proton concentration in the specimen.
Ga-doped ZnO layers were grown on sapphire substrates by molecular beam epitaxy (MBE). Low-temperature photoluminescence (PL) and room-temperature Raman spectra were investigated. Defect-related modes at 277 and 510 cm−1 appeared in the Raman spectrum for Ga-doped layers. The PL spectrum is dominated by a donor-bound exciton peak at 3.356 eV. A weak yellow luminescence (YL) band peaking at 2.1-2.2 eV was studied in detail. It shifted to higher photon energies (up to 0.1 eV) with increasing excitation intensity. The YL band is attributed to transitions from shallow donors to a deep acceptor. The acceptor is thought to be a Zn vacancy-related defect because the intensity of the YL band decreased dramatically with Ga doping.
Platinum nanoparticles were dispersed in mesopores of mesoporous silica using a sol-gel process with a composite template consisting of an amphiphilic triblock copolymer (Pluronic P123 or F127) and a Pt-organic complex, which was prepared with K2Pt(II)Cl4 as a Pt source and 1,10-phenanthroline as a chelating agent. The obtained Pt-1,10-phenanthroline complex did not dissolve in any of several solvents, e.g., hexane, benzene, toluene, THF, H2O, CH3OH, and C2H5OH. However, when the Pt-1,10-phenanthroline complex was reacted with ethylenediamine it dissolved in many solvents. Platinum nanoparticles dispersed in mesoporous silica were obtained using a sol-gel process with a complex template consisting of Pt-1,10-phenanthroline-ethylenediamine, and an amphiphilic triblock copolymer (Pluronic P123 or F127). A sample dried at 353 K was bright yellow. When it was subsequently heat-treated at 823 K, it turned light gray. This change indicates that Pt nanoparticles can be obtained by heat-treatment at high temperature, because, to generate Pt nanoparticles, the organics chelated to Pt ions must be removed. Measurements from small-angle x-ray scattering show that mesoporous silica obtained using a complex template has a much more highly ordered pore structure than that obtained using only an amphiphilic triblock copolymer. It has both large pores (above 8 nm) and a large surface area (about 290 m2/g). Furthermore, results of a TEM investigation showed that Pt nanoparticles were generated only in mesopores of mesoporous silica.
A new nonlinear travelling-wave solution for a flow through an isothermal square duct is discovered. The solution is found by a continuation approach in parameter space, starting from a case where the fluid is heated internally. The Reynolds number for which the travelling wave emerges is much lower than that of the solutions discovered recently by an analysis based on the self-sustaining process (Wedin et al., Phys. Rev. E, vol. 79, 2009, p. 065305; Uhlmann et al., Advances in Turbulence XII, 2009, pp. 585–588). Furthermore, the new travelling-wave solution is shown to be unstable from the onset.
We have developed a Wide Field Cryogenic Telescope II (WFCT-II), which contains
a whole telescope-optics in a cryostat to suppress thermal emission from the whole telescope.
The cryostat is of a cylindrical shape of 800 mm length and 300 mm diameter.
The telescope inside is a Ritchey-Chretien system with the primary mirror of 231 mm in diameter
and a focal length of 1500 mm. The InSb 1k × 1k infrared array detector (Aladdin II) has a FoV of 1 square degree
and a resolution of 3'' × 3''/pixel. We can install 5 filters whose wavelengths range from 1 μm to 5 μm.
We analyse the stability of plane Poiseuille flow with a streamwise system rotation. It is found that the instability due to two-dimensional perturbations, which sets in at the well-known critical Reynolds number, Rc = 5772.2, for the non-rotating case, is delayed as the rotation is increased from zero, showing a stabilizing effect of rotation. As the rotation is increased further, however, the laminar flow becomes most unstable to perturbations which are three-dimensional. The critical Reynolds number due to three-dimensional perturbations at this higher rotation case is many orders of magnitude less than the corresponding value due to two-dimensional perturbations. We also perform a nonlinear analysis on a bifurcating three-dimensional secondary flow. The secondary flow exhibits a spiral vortex structure propagating in the streamwise direction. It is confirmed that an antisymmetric mean flow in the spanwise direction is generated in the secondary flow.