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Verticillium dahliae infecting tomato can be differentiated into races 1 and 2 based on differential pathogenicity on tomato cultivars carrying resistance gene Ve1. Although no commercial cultivars resistant to race 2 are available, race 2-resistant rootstock cultivars Aibou and Ganbarune-Karis have been bred in Japan. Nevertheless, the resistance of these rootstocks appears to be unstable in commercial tomato fields. Pathogenicity assays conducted under controlled conditions revealed that these rootstock cultivars are resistant to some isolates of race 2; this resistance is controlled by a single dominant locus, denoted by V2, based on segregation of resistance in F2 populations from selfed rootstock cultivars. However, some other isolates of race 2 can overcome this resistance. Therefore it is proposed that the current race 2 of V. dahliae should be divided into two races, i.e. ‘race 2’ (nonpathogenic on Aibou) and ‘race 3’ (pathogenic on Aibou). The distribution of these races was surveyed in 70 commercial tomato fields in Hida, Gifu Prefecture, Japan. Race 3 was found in 45 fields, indicating that race 3 had already spread throughout the region. On the other hand, 25 fields had only race 2, and thus race 2-resistant rootstocks would be effective for disease management in these fields. Races 2 and 3 could not be identified by genomic Southern hybridization probed with a telomere sequence, nor with previously reported race-specific PCR assays. Elucidation of race-determining mechanisms and development of methods for quick race identification should be made in future studies.

Plant–fungal specificity between cucurbitaceous crops and Diaporthe sclerotioides, the causal agent of black root rot, was studied using cucumbers (Cucumis sativa), melons (Cucumis melo), pumpkins (Cucurbita maxima), watermelons (Citrullus lanatus) and bottlegourd (Lagenaria siceraria var. gourda). Twelve D. sclerotioides isolates from these cucurbit species were cross-inoculated. The virulence of the isolates was evaluated as the area under the disease progress curve (AUDPC). All cucurbit species were susceptible to each isolate, but AUDPCs were significantly different among the hosts, with the order of greatest to least being melon, cucumber, watermelon, bottlegourd and finally, pumpkin. The infectiveness of isolates was assessed as the quantity of D. sclerotioides DNA detected in the hypocotyls of seedlings 2 weeks after inoculation using a real-time PCR protocol. The fungal DNA quantities varied among the species in the same order as the AUDPCs. Whilst there were statistically significant correlations between the virulence and infectiveness of D. sclerotioides isolates in cucumbers, melons and bottlegourds, their coefficients of determination were not high (r2

An improved microwave plasma system is proposed to form planarized SiO/sub 2/ interlayers for LSIs. A high planarization rate was achieved by controlling the formation of a cylindrical plasma and by adjusting the frequency applied to the substrate by which ions can be impinged onto the substrate at a maximum speed. Electric damage was decreased by using oxygen ion sputtering and by suppressing the stimulated bias voltage. These features ensure that a low-damage, planarized SiO/sub 2/ film is formed at a rate of more than 200 nm/min without a stimulated bias voltage. >

A simple method using ion-pair high-performance liquid chromatography was established for the rapid and precise determination of honokiol(3',5-di-2-propenyl-1,1'-biphenyl-2,4'-diol) and magnolol(5,5'-di-2-propenyl-1,1'-biphenyl-2,2'-diol) in eighteen species of oriental pharmaceutical decoctions containing Magnolia bark. An ODS column and a mixed solvent system of water involving 10 mM tetra-n-amyl-ammonium bromide (TAA) and acetonitrile (4:6) as a mobile phase were used for the separation. Honokiol and magnolol were eluted without interference of other coexisting components within 12 min.

A simple method using ion-pair high-performance liquid chromatography was established for the rapid and precise determination of sennoside A in oriental pharmaceutical decoctions containing Rhei Rhizoma. This method was compared with other two methods, i.e. ion-suppression and phosphate buffer methods. Sennoside A was eluted without interference in this ion-pair method, while the determination of sennoside A was interfered by co-existing components in the other two methods.

Mesures DLTS des niveaux d'energie des pieges et de leurs concentrations suivant l'ordre de diffusion de Au et Pt (influence de la temperature). Interpretation par la presence de Au et Pt sur les memes sites de substitution dans Si

The effects of hydrogen annealing on reverse current-voltage characteristics of a zinc borosilicate glass passivated p-n junction with a negative net number of charges N at the glass-silicon interface have been studied. It was shown that a negative N contributed to raising the breakdown voltage, and the stepped reverse current-voltage characteristics could be found owing to this. The avalanche breakdown voltage and leakage current decreased with hydrogen annealing. These results were discussed in terms of a positive shift in the negative N associated with the decrease of the acceptor type interface trap density. The effective capture cross section in the glass-silicon system studied was found to be less than 5 x 10/sup -16/ cm/sup 2/.

The BV CB0 leakage current h FE were studied for high-voltage planar transistors which had three kinds of passivation films; SiO 2 -semi-insulating polycrystalline silicon (SIPOS)-SiO 2 ; SIPOS-SiO 2 ; and SiO 2 -phosphosilicate glass (PSG)-SiO 2 . The SiO 2 -SIPOS-SiO 2 type had a lower leakage current (surface generation current) and higher h FE than the conventional SIPOS-SiO 2 type. The SiO 2 -SIPOS-SiO 2 type also had the highest BV CB0 due to the field-plate effect.

Bipolar transistors of high cut off frequency ( f_{T}=9 GHz) and small size have been fabricated on the same chip with a standard CMOS using the buried twin well structure. 1.3 µm LDD CMOS FETs were formed in the thin epitaxial layer(1-1.5µm) with the buried twin well, without degrading the device characteristics of the MOS FET. Ring oscillators of the BiCMOS gate have been fabricated. A 0.4ns gate delay time at 0.6pF and 3.5 times larger driveability than that of the same area CMOS gate were obtained.

This paper describes the high performance BiCMOS (Hi-BiCMOS) device technology and discusses the scalability to sub-micron. As the device structure is scaled down from 2 µm to 1.3 µm, BiCMOS circuit performance is improved by the factor of the scaling. By further scale down to 0.8 µm, a 0.27 ns gate delay in BiCMOS gate and 5.5 ns access time of 64kbit BiCNOS ECL RAN are expected.

A Self-aligning Polysilicon ELectrode technology (SPEL) is proposed to realize future high performance LSIs. This technology, based on a preferential dry etching of a highly doped polysilicon, makes it possible to halve the contact region areas of MOS and bipolar transistors as compared to conventional ones. Additionally, reduction of parasitic capacitance and resistance are demonstrated for the former transistors.

Mesures DLTS des niveaux d'energie des pieges et de leurs concentrations suivant l'ordre de diffusion de Au et Pt (influence de la temperature). Interpretation par la presence de Au et Pt sur les memes sites de substitution dans Si

A novel scaled down high resistor (1µm or less in length) for future static RAMs was realized by using the slow arsenic diffusion in oxygen implanted polysilicon, where arsenic is partially doped to form polysilicon interconnection layer. The current voltage characteristics of the oxygen doped polysilicon resistors were almost linear, and the marked decrease in resistance for higher applied voltage, observed in non-doped polysilicon, could not be found. Moreover the field effect modulation of the resistance in the oxygen doped polysilicon was much less than that of non-doped one. Applicability of the scaled down oxygen implanted polysilicon resistor was thus demonstrated for future static RAMs.

A high breakdown voltage for a planar junction has been achieved by using a layer of oxygen doped amorphous silicon film over a composite of chemical-vapour deposition (CVD) phosphosilicate glass (PSG) film, CVD SiO2 film, and thermally oxidised SiO2. The high breakdown phenomenon was analysed from the viewpoint of surface depletion layer width. Measurements of the surface depletion layer width by scanning laser microscope, and numerical calculations of a 2-dimensional Poisson's equation for the distributed potential in oxygen doped amorphous silicon showed close agreement. The distributed potential of oxygen doped amorphous silicon influenced induction of the surface depletion layer, resulting in a reduced surface electric field and higher breakdown voltage. The leakage current of oxygen doped amorphous silicon was negligible at high temperatures (>125°C) compared to the normal junction leakage current. This was due to the low activation energy of conductivity for oxygen doped amorphous silicon.