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The effect of eddy current dampers on the vibrational properties in superconducting levitation has been investigated using melt-processed YBaCuO bulk superconductors. In vertical vibration, the damping was about 100 times improved by inserting eddy current dampers into the gap between a superconductor and a magnet. On the other hand, in horizontal vibration, eddy current dampers did not greatly affect the vibrationaal properties of superconducting levitation up to a given thickness of eddy current dampers.

The vibrational properties in superconducting levitation using melt-processed YBaCuO superconductors have been investigated. In both vertical and horizontal vibrations, the resonant frequency linearly decreases when increasing the gap between superconductors and a magnet. Resonant frequencies of 1–2 Hz can be achieved for larger initial gaps in the horizontal vibration. The effect of the load-weight on the resonant frequency is small for all initial gaps in vertical and horizontal vibrations, except for smaller gaps in the vertical vibration. The fact that the resonant frequency in superconducting levitation is almost completely unaffected by the change in load weight is due to the levitation force properties.

We demonstrated the operation of GaInAs/AlAs resonant tunneling diode (RTD) oscillators with high output power (100–200 µW) at frequencies of 430–460 GHz using an offset-fed slot antenna, in which the RTD was placed 45 µm from the center of a 100-µm-long antenna. The highest output power obtained in this study was 200 µW at 443 GHz for a single RTD with a peak current density of 18 mA/µm2. The output powers of 50–130 µW at frequencies of 460–490 GHz were also obtained in the oscillators with different structure. Higher output is expected by optimizing the position and mesa area of the RTD and the antenna length.

We report experimental and theoretical results on the increase in output power of resonant tunneling diode (RTD) oscillators in sub-terahertz (THz) range with an offset-fed slot antenna and high current density. Theoretical analysis shows that the oscillation frequency increases with an offset from the center of the slot antenna. Output power also increases with the offset up to the point of the best impedance matching. As the result of calculation, the oscillation at 600 GHz with the output power of 610 μW is expected for a single RTD with high peak current density (18 mA/μm2) and an offset structure. In a preliminary experiment, an output power of 150 μW was obtained at 271 GHz with peak current density of 7 mA/μm2.

A fundamental oscillation of up to 831 GHz was observed at room temperature in GaInAs/AlAs resonant tunneling diodes integrated with planar slot antennas. The thickness of the collector spacer layer was optimized (20 nm) and the mesa area (≪1 µm2) was reduced in order to reduce the resonant tunneling diode capacitance. Reduction in the negative differential conductance in the small mesa area was prevented by increasing the emitter doping concentration (3 × 1018 cm−3) which resulted in an ultra-high peak current density (18 mA/µm2) with a peak-to-valley current ratio of 2. The dependence of oscillation frequency on the mesa area was also studied. The output power was at least 1 µW.

Low density polyethylene (LDPE) is widely used as a dielectric insulation of power cable. It has already reported that an incorporation of MgO nanoparticles in LDPE matrix could provide dielectrics with new and improved properties under dc high field. However under ac high field, it has already reported that the effect of the addition of MgO nanoparticles was relatively small compared with that under dc high field. This paper describes the dissipation current waveform and the electroluminescence (EL) of LDPE/MgO nanocomposite material under the high field trapezoidal waveform application by using the simultaneous observation system. From the results of experiments, the EL image and the relation between the dissipation current and the EL under high field trapezoidal waveform application were introduced.

Low density polyethylene (LDPE) is widely used as a dielectric insulation of power cable. It has already reported that an incorporation of MgO nano particles in LDPE matrix could provide dielectrics with new and improved properties under dc high field. This paper describes high field dielectric properties of LDPE/MgO nano composite material under ac high voltage application. From the results of dissipation current waveform observations under ac high field, the volume resistivity and the relative permittivity for various contents of MgO nano particles in LDPE were estimated at the applied frequency 50 and 200 Hz. Though, the dependences of MgO content on both volume resistivity and relative permittivity under ac high field at 50 and 200 Hz are recognized, but it seems not to be drastically improved by adding a few percent of nano-size filler like those under dc high field.

To achieve effective k value less than 3.0, we investigated spin-on dielectric stack damascene integration scheme with electron beam (EM) cure. By using porous-MSQ (k=2.3) as ILD and dense-MSQ (k=2.9) as hard mask (HM), effective k value could be lowered, and by EB curing the full dielectric stack only once, mechanical strength for both ILD and HM were improved and a reduced thermal budget was obtained. In addition, a low damage resist strip process for the low-k materials was evaluated. These elements of BEOL technology have applicability to 45nm technology node and beyond.

Self-incompatibility (SI) in Brassica is sporophytically controlled by the multi-allelic S locus. SI phenotypes of the stigma and pollen in an S heterozygote are determined by the two S haplotypes it carries; the two haplotypes may be co-dominant or exhibit a dominant/recessive relationship. Because the S receptor kinase (SRK) gene of the S locus was recently shown to determine the S haplotype specificity of the stigma, we wished to investigate whether SRK also plays a role in the dominance relationships between S haplotypes. We crossed plants carrying an SRK28 transgene with plants homozygous for one of five S haplotypes that are either co-dominant with, or recessive to, S28 haplotype in the stigma, and analyzed the SI phenotypes of the progeny. In all cases, the SI phenotype of the stigma of plants carrying the SRK28 transgene could be predicted by the known dominance relationships between the S haplotype(s) and the S28 haplotype. Moreover, in the S43 homozygote carrying the SRK28 transgene where the S43 phenotype in the stigma was masked by the presence of the SRK28, the transcript level of SRK28 was found to be much lower than that of SRK43. All these results suggest that the dominance relationships between S haplotypes in the stigma are determined by SRK, but not by virtue of its relative expression level.

Nuclear factor kappaB (NF-kappaB) gene-regulatory proteins play important roles in inflammation, neoplasia, and programmed cell death. Recently, blockade of NF-kappaB function has been shown to result in epithelial hyperplasia, suggesting a potential role for NF-kappaB in negative growth regulation. We expressed active NF-kappaB subunits in normal epithelial cells and found that NF-kappaB profoundly inhibits cell cycle progression. This growth inhibition is resistant to mitogenic stimuli and is accompanied by other features of irreversible growth arrest. NF-kappaB-triggered cell cycle arrest is also associated with selective induction of the cyclin-dependent kinase inhibitor p21CiP1, with overexpression of p21(Cip1) alone inducing findings similar to those seen with NF-kappaB in vitro. An active NF-kappaB subunit expressed in the epidermis of p21(CiP1-/- mice, however, displays only partial growth-inhibitory effects, suggesting that full NF-kappaB growth inhibition is only partially p21(Cip1) dependent in this setting. These data indicate that NF-kappaB can trigger cell cycle arrest in epithelial cells in association with selective induction of a cell cycle inhibitor.

Self-incompatibility (SI) in Brassicaceae is genetically controlled by the S locus complex in which S locus glycoprotein (SLG) and S receptor kinase (SRK) genes have been identified, and these two genes encoding stigma proteins are believed to play important roles in SI recognition reaction. Here we introduced the SLG43 gene of Brassica rapa into a self-incompatible cultivar, Osome, of B. rapa, and examined the effect of this transgene on the SI behavior of the transgenic plants. Preliminary pollination experiments demonstrated that Osome carried S52 and S60, and both were codominant in stigma, but S52 was dominant to S60 in pollen. S43 was found to be recessive to S52 and codominant with S60 in stigma. The nucleotide sequence of SLG43 was more similar to that of SLG52 (87.8% identity) than to that of SLG60 (74.8% identity). Three of the ten primary transformants (designated No. 1 to No. 10) were either completely (No. 9) or partially (No. 6 and No. 7) self-compatible; the SI phenotype of the stigma was changed from S52S60 to S60, but the SI phenotype of the pollen was not altered. In these three plants, the mRNA and protein levels of both SLG43 and SLG52 were reduced, whereas those of SLG60 were not. All the plants in the selfed progeny of No. 9 and No. 6 regained SI and they produced a normal level of SLG52. These results suggest that the alteration of the SI phenotype of the stigma in the transformants Nos. 6, 7, and 9 was the result of specific co-suppression between the SLG43 transgene and the endogenous SLG52 gene. Three of the transformants (Nos. 5, 8 and 10) produced SLG43 protein, but their SI phenotype was not altered. The S60 homozygotes in the selfed progeny of No. 10 which produced the highest level of SLG43 were studied because S43 was codominant with S60 in the stigma. They produced SLG43 at approximately the same level as did S43S60 heterozygotes, but did not show S43 haplotype specificity at the stigma side. We conclude that SLG is necessary for the expression of the S haplotype specificity in the stigma but the introduction of SLG alone is not sufficient for conferring a novel S haplotype specificity to the stigma.

Self-incompatibility in Brassica is controlled by a single multi-allelic locus (S locus), which contains at least two highly polymorphic genes expressed in the stigma: an S glycoprotein gene (SLG) and an S receptor kinase gene (SRK). The putative ligand-binding domain of SRK exhibits high homology to the secretory protein SLG, and it is believed that SLG and SRK form an active receptor kinase complex with a self-pollen ligand, which leads to the rejection of self-pollen. Here, we report 31 novel SLG sequences of Brassica oleracea and Brassica campestris. Sequence comparisons of a large number of SLG alleles and SLG-related genes revealed the following points. (i) The striking sequence similarity observed in an inter-specific comparison (95.6% identity between SLG14 of B. oleracea and SLG25 of B. campestris in deduced amino acid sequence) suggests that SLG diversification predates speciation. (ii) A perfect match of the sequences in hypervariable regions, which are thought to determine S specificity in an intra-specific comparison (SLG8 and SLG46 of B. campestris) and the observation that the hypervariable regions of SLG and SRK of the same S haplotype were not necessarily highly similar suggests that SLG and SRK bind different sites of the pollen ligand and that they together determine S specificity. (iii) Comparison of the hypervariable regions of SLG alleles suggests that intragenic recombination, together with point mutations, has contributed to the generation of the high level of sequence variation in SLG alleles. Models for the evolution of SLG/SRK are presented.

The nucleotide (nt) sequences of the 5'-flanking regions of two Brassica self-incompatibility genes, SLG9 and SRK9, were determined. Their sequences were highly conserved: a region spanning 1.9 kb in the 5'-flanking region was completely identical except for a 1319-bp segment in SLG9. These observations strongly suggest that SLG9 and SRK9 together with their promoter regions were involved in a gene duplication or conversion event which occurred before the 1319-bp SLG9-specific sequence was inserted in SLG9 or deleted in SRK9.

We isolated 12 groups of genomic clones that contained SLG-homologous regions from a genomic library constructed from an S9 homozygote of self-incompatible Brassica campestris. Both SLG9 and SRK9 genomic clones, which are located within the self-incompatibility (S) locus, were included in these groups. The promoter regions of SLG9 and SRK9 were completely identical for at least 200 bp upstream from their respective initiation codons (ATG). The five sequence elements (boxes I to V) that are conserved in the promoters of SLG and SRK genes were also found in the SLG9 and SRK9 clones. However, one conserved element (box III) unexpectedly lacked 7 of 11 bp, although box III has been considered necessary for expression in pistil. The other ten groups of genomic clones were classified into six SRK-like groups and four SLG-like groups. These results indicate that SLG, SRK, SLG-like, and SRK-like genes form a large S-multigene family in B. campestris.

A cDNA clone encoding NS3-glycoprotein was isolated from stigmas of Brassica campestris. NS-glycoproteins correspond to the SLR1-glycoproteins of B. oleracea and are highly conserved within the species. These data suggest that the NS-glycoproteins may play a role in discrimination between species in the fertilization system of Brassica.

S-glycoproteins, i.e. stigma glycoproteins that are heritable in correlation with S allele in self-incompatible Brassica species, were apparently purified for three S alleles in B. oleracea. From SDS gel electrophoresis, the estimated molecular weight for two of the S-glycoproteins was 57,000. The other S-glycoprotein was considered to be heterogeneous with molecular weights of 60,000 and 65,000. Distinct differences in amino acid content were found; in general, cysteine, methionine and histidine were low, and serine, glutamate, glycine, leucine, arginine and aspartate were high and variable between the S-glycoproteins. Differences in the isoelectric point were mainly attributed to the amino acid composition of each S-glycoprotein.

A number of contributions on the genetics of self-compatibility vs. -incompatibility in Crucifers may suggest that there are two cases for the appearance of self-compatible plants in self-incompatible ones. The first is due to the changes or the interactions of S alleles (Bateman 1954, Sampson 1957, Thompson and Taylor 1966, Zuberi et al 1981), and the second is that self-compatibility is ascribed to genes different from S alleles (Murakami 1965, Thompson and Taylor 1971, Nasrallah 1974, Hinata et al 1983).

Egg plant (Solanum melongena L.), also known as brinjal is probably a native of southern Asia, while in general the genus Solanum is predominant in the New World. There are Sanskrit names for it in a book that was probably written in between the 3rd century B. C. and the 3rd century A. D. (Kahn 1979). Its cultivation was known in the area ranging from China to Persia by the 5th century, and it was not known in Europe until the 13th century (Hedrick 1972).