Effects of insect predation on hypocotyl survival and germination success of maturequercus variabilis acorns

The rates of hypocotyl and radicle survival and of germination success were investigated in mature acorns ofQuercus variabilis Blume in relation to endosperm loss due to seed insects. The acorns were damaged by curculio weevils (Coleoptera: Curculionidae) and moths, including tortricid moths (Lepidoptera: Tortricidae); the former were more abundant than the latter. Acorns damaged by curculio weevils showed a significantly lower germination rate when there was a large endosperm loss than the rate for sound acorns. The survival rate of the hypocotyl and radicle also decreased as endosperm loss increased. These results suggest that acorn germination is directly inhibited by damage to the hypocotyl and radicle, which depends on the amount of endosperm eaten by the weevils. However, the germination rate of acorns with hypocotyl and radicle was consistently high, irrespective of the degree of endosperm loss, which suggests that weevil-damaged acorns probably germinate, provided the hypocotyl and radicle survive until the cessation of damage. Research Fellow of the Japan Society for the Promotion of Science. This study was supported in part by Grants-in-Aid for Scientific Research from the Japan Ministry of Education, Science and Culture (No. 09001647, No. 10660144, and No. 11460068) and the Nippon Life Insurance Foundation.     

Automatic detection of a damaged cutting tool during machining I: method to detect damaged bandsaw teeth during sawing

This paper presents an on-line method for detecting damaged teeth in the bandsaw using acoustic emission (AE) signal energy. The method is based on an analysis of differences in AE energies generated by normal and damaged teeth during sawing. Because of the difference in the amount of sawing, the AE energy was low for sawing by the damaged tooth and high for sawing by the normal tooth immediately after the damaged tooth. The ratio of AE energy for two successive teeth — a normal tooth immediately following a damaged tooth — was much greater than 1, whereas the ratio of AE energy for two successive normal teeth was close to 1. The results demonstrate that the technique using the AE energy ratio for two successive teeth is effective for on-line detection of damaged bandsaw teeth.Part of this paper was presented at the 9th Annual Meeting of the Chugoku Skikoku Branch of the Japan Wood Research Society, Tottori, October 1997     

Prevalence of equine herpesvirus type 1 strains of neuropathogenic genotype in a major breeding area of Japan

A single non-synonymous nucleotide substitution of guanine (G) for adenine (A) at position 2254 in the viral DNA polymerase gene (encoded by open reading frame [ORF] 30) of equine herpesvirus type 1 (EHV-1) has been significantly associated with neuropathogenic potential in strains of this virus. To estimate the prevalence of EHV-1 strains with the neuropathogenic genotype (ORF30 G(2254)) in the Hidaka district--a major horse breeding area in Japan--we analyzed the ORF30 genomic region in cases of EHV-1 infection in this area during the years 2001-2010. Of the 113 cases analyzed, 3 (2.7%) were induced by ORF30 G(2254) strains. This prevalence is lower than those observed in the U.S.A. (10.8-19.4%), Argentina (7.4%), France (24%), and Germany (10.6%).     

Expression of amphiregulin during the pre- and post-implantation period in the mouse reproductive tract

In mammals, embryo implantation is an essential step in reproduction. Implantation is a phenomenon that involves crosstalk between the blastocyst and the maternal endometrium. However, the molecular basis of the connections between the blastocyst and endometrium is not yet fully understood. Amphiregulin is a member of the epidermal growth factor family and is known to be expressed in the luminal epithelium of the mouse uterus on 3.5 days post coitum (dpc). Thus, to clarify the mechanism of amphiregulin at fetomaternal interface, we analyzed the expression pattern of amphiregulin mRNA in the oviducts and uteri of pregnant and psuedopregnant mice by means of real-time PCR. Amphiregulin expression in the pregnant uterus dramatically increased on 2.5 dpc, peaked on 3.5 dpc, and declined by 5.5 dpc. Furthermore, to analyze the effect of the presence of an embryo on amphiregulin expression, we determined the expression pattern of amphiregulin mRNA in the uterus after embryo transfer on 0.5 and 1.5 dpc. A previous study showed that the expression of amphiregulin mRNA depends on the concentration of progesterone. However, our present results indicate that amphiregulin mRNA is upregulated by the presence of fertilized eggs in the lumen of the oviduct on 0.5 dpc.     

Development of a screening method for genetically modified soybean by plasmid-based quantitative competitive polymerase chain reaction

A novel type of quantitative competitive polymerase chain reaction (QC-PCR) system for the detection and quantification of the Roundup Ready soybean (RRS) was developed. This system was designed based on the advantage of a fully validated real-time PCR method used for the quantification of RRS in Japan. A plasmid was constructed as a competitor plasmid for the detection and quantification of genetically modified soy, RRS. The plasmid contained the construct-specific sequence of RRS and the taxon-specific sequence of lectin1 (Le1), and both had 21 bp oligonucleotide insertion in the sequences. The plasmid DNA was used as a reference molecule instead of ground seeds, which enabled us to precisely and stably adjust the copy number of targets. The present study demonstrated that the novel plasmid-based QC-PCR method could be a simple and feasible alternative to the real-time PCR method used for the quantification of genetically modified organism contents.     

Prediction of the buckling stress of intermediate wooden columns using the secant modulus

We made several buckling tests of wooden columns with intermediate slenderness ratios () and examined the empirical formulas. On the basis of the examination, we formulated an equation for predicting the buckling stress () of an intermediate wooden column. Sitka spruce (Picea sitchensis Carr.) and buna (Japanese beech, Fagus crenata BI.) were used for the studies. A compressive load was applied on the specimen supported with pin ends, and the buckling stress was predicted by the tangent modulus theory and two empirical equations: those of Tetmajer and Newlin-Gahagan. The predicted - relations were compared with the test results, and the applicability of these predictions were examined. Based on the comparisons, we formulated an equation that can predict the - relations of materials with various stress-strain characters in the plastic strain range.     

Accumulation of Glucosamine in the Methanolic Extract Of Corn Shoots Grown without Zinc Supply

Cadmium levels were determined in rice grains of Japonica, Indica, Javanica, and Indica-Japonica hybrid-bred varieties that were produced in the same plot of a non-polluted field in 1983 and 1985, using nameless atomic absorption spectrophotometry.

Cadmium levels in the brown rice grains harvested in 1983 and 1985 ranged from 2.1 to 27 0 ppb Cd for 28 Japonica varieties, 4.1 to 55.5 for 23 Indica varieties, 4.4 to 16.5 for 5 Javanica varieties, and 24.5 to 73.6 for 4 hybrid varieties.

The significant correlation of the cadmium levels between the 1983 and 1985 products may indicate the possible occurrence of varietal differences in the natural abundance of cadmium in rice grains. There was no correlation between the cadmium levels and the duration of ripening in each variety, suggesting that these differences could be partly attributed to some physiological characteristics of the rice varieties.