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Invasion of alien plant species can have irreversible effects on ecosystems. Although alien plants often distribute in disturbed area, understanding of the initial invasion process soon after disturbance is poor. We compared forest floor vegetation between thinning treatment plots and intact control plots in a red pine (Pinus densiflora) forest in central Japan to test whether the thinning treatment (i.e. disturbance) induced invasion of alien plants. We also examined how invasion of aliens is influenced by the environment, plant traits, and buried seeds in the soil. In control plots, few alien plants emerged at the herbaceous layer and only a few buried seeds of alien plants were found. In treatment plots, on the other hand, many alien plants were observed both at the herbaceous layer and in the soil seed bank. Treatment plots had a larger percentage of canopy openness than control plots. In treatment plots, the cover of alien plants was negatively correlated with the distance from the nearest primary road. Alien plants had taller maximum plant height, larger leaves, and greater leaf nitrogen concentration than native species in treatment plots. This indicates that alien plants were superior to native plants in growth, competition, and carbon assimilation abilities. Alien plants tended to have seeds with long dispersal abilities, such as anemochory and zoochory, and short life histories, such as annual and biennial histories. These findings suggest that thinning promoted invasion of alien plants and that alien plants had the potential for further invasion by rapid dispersion, establishment, and growth.

We compute the homotopy groups of the space of self maps of the 3 dimensional projective space.

We compute the homotopy groups of the spaces of self-maps of SU(3) and Sp(2).

In the previous paper, it was reported that ethylene oxide and propylene oxide had the mold-inhibiting effect on Manju.Gaseous residues in Manju after the treatment were determined by gas chromatographic method.The effect on growth of rats by the treated Manju was evaluated.1. Residual amounts of ethylene oxide in thetreated Manju were generally lower than those of propylene oxide.2. When rats were fed with the treated Manju, their body weight increased regulary in each of the groups, though the color of liver lipid of the control group and propyleneoxide administered one showed brilliant yellow, while that of ethylene oxide group reddish yellow.3. The taste of treated Manju was as tastefull as control but water and navor in Manju were relatively evaporated.

As the ratio of beet sugarin the mixture with cane sugar for biscuit manufacturing increased, trends of lighter color, more spread and friability, and less stability of fat were observed in the resulting product. The products with single use of beet and cane sugar, respectively, contained higher moisture than those with mixed sugar. Little difference was detected by sensory evaluation among the products with different sugar formulas.