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11.
Kazuyuki Fujita Koji Hirano Michiharu Kawanishi Naota Ohsaki Makoto Ohtaishi Eizi Yano Makoto Yasuda 《Researches on Population Ecology》1978,19(2):209-221
Summary Adult population of a dragonflyNannophya pygmaea
Ramber inhabited in a damp ground was investigated with mark-and-recapture method in 1975. The following results about the seasonal
changes of the population size and distribution in the habitat were obtained.
Adults emerged from late May to mid August. The number of the adults was most abundant in early June, but that of matured
males in early July. From the recapture data, the estimate of daily survival rate was 0.82, and the length of immature stage
in males was estimated as 5 days or so. Total number of post-teneral adults emerged in the habitat was estimated as about
9,000. The mean crowding-mean density regression method was applied for the analysis of the distribution pattern of the adults.
Matured males showed a spaced-out distribution, while females and immatured males distributed themselves rather aggregatively.
Such a distribution pattern of the matured male would be attributed to their territorial behaviour. The territorial behaviour
was considered to force the matured males to extend the distribution area in July when they were most abundant.
From the above-mentioned results and some observations, the meaning of the territoriality in this species was discussed. 相似文献
12.
Summary We studied the relationship between the diurnal nectar secretion pattern of flowers ofCayratia japonica and insect visiting patterns to these flowers. Flower morphology ofC. japonica changed greatly for about 12 hours after flower-opening and the maximum duration of nectar secretion was 2 days. The nectar
volume peaked at 11∶00 and 15∶00, and declined at night and at 13∶00 regardless of time elapsed after flower-opening. The
nectar volume at the two peaks was, on average, 0.25 μl on bagged inflorescences and 0.1μl on unbagged inflorescences (both,
sugar concentration=60%). The flower secreted nectar compensatory when the nectar was removed. This means that insects consume
more nectar than the difference of nectar volume between bagged and unbagged flowers.
Apis cerana is a primary visitor of this flower, and was the only species for which we confirmed pollen on the body, among many species
of flower visiting insects to this flower.Apis cerana visited intensively at the two peaks of nectar secretion. Visits of the other insects were rather constant or intensive only
when there was no nectar secretion. Thus flowers ofC. japonica with morphologically unprotected nectaries may increase likelihood that their nectar is used by certain pollinators, by controlling
the nectar secretion time in day. In this study the pattern of nectar secretion allowedA. cerana maximum harvest of nectar.
Contribution to the ecological and bioeconomoical studies of the pollinator community in Kyoto I. 相似文献
13.
14.
Among wild plants ofHydrangea serrata (Hydrangeaceae) in Japan, there are sweet plants whose leave contain a kind of isocoumarin, phyllodulcin, which happens to
be 350 times as sweet as sucrose to the human tongue. In a primary beech forest in Ashu, Kyoto, the spatial distribution of
sweet plants and temporal and the spatial distribution of phyllodulcin within and among plants were investigated using a high
performance liquid chromatograph. The distribution of sweet plants was confined within a valley and was parapatric with non-sweet
plants. A plant's characteristic phyllodulcin accumulation did not change, even when transplanted into the different habitats.
The phyllodulcin content of the sweet plants varied greatly among plants, and the population mean peaked in July when the
plants flowered. Within a plant, phyllodulcin content was elevated by partial defoliation. We examined the possible effect
of phyllodulcin on herbivory by a specialist leafmining herbivore,Antispila hydrangifoliella (Lepidoptera: Heliozelidae). We transplanted sweet and nonsweet plants reciprocally between their original habitats, excluded
attacks by parasitoids, and compared performance of the leafminer. Leafminer colonization and larval survivorship on transplanted
andin situ plants was not significantly different between sites. The fact that accumulation of phyllodulcin did not augment a defensive
function, at least against herbivory by the leafminer, and the sporadic distribution of phyllodulcin-accumulating plants,
suggest that the genotypes synthesizing phyllodulcin emerged independently at separate localities by mutation, and that the
genotypes are almost adaptively neutral in defence against the specialist herbivore. 相似文献
15.
Makoto Maejima 《Revue canadienne de statistique》1986,14(1):81-82
The upper bound of the parameter of self-similar processes with stationary increments is given in terms of the moment condition. 相似文献
16.
We study second-order properties of a two-stage fixed -size confidence region for estimating the mean vector μ in the Np(μ∑) population when some auxiliary information about the structure of ∑ is available. In the case when we do not have such nrior information regarding ∑. Mukhopauiiyay (199/ ) de rived second-order properties of the classical two stage fixed-size confidence region, when properly modified. It was assumed that the maximum latent root of ∑ was simple and bounded below by a known positive number. In this paper we allow the maximum latent root to have general multiplicity for the verification of the second order properties of the two-stage procedure incorpo rating ∑'s structural information. We also maintain the nominal confidence coefficient. 相似文献
17.
Although a macro‐organizational perspective has become increasingly commonplace in social movement analyses, few studies examine the full spectrum of organizations in any single social movement industry (SMI). Utilizing a unique source of data on Japanese environmental movement organizations, we compare characteristics of groups focused primarily on environmental issues with those for whom environmental issues are part of a larger multi‐issue focus. We then profile across distinct, and theoretically important, organizational domains to assess how local, prefectural and national groups compare on a variety of organizational attributes, including: size, membership type, tactics and activities, and issues. We conclude by discussing the implications of our findings for understanding both Japanese environmentalism and the structure of SMIs generally. 相似文献
18.
Makoto Narita Mohammod M. Islam Michael E. Rogers Daisuke Koizumi 《Journal of women & aging》2013,25(3):237-250
Falls represent a major public health problem for older adults, and loss of balance (LOS) abilities is one of the primary causes of falls. Previous studies have shown that balance training is effective in improving physical function and decreasing risk of falls. However, little attention has been given specifically to balance training in older adults with very poor balance. The purpose of this study was to determine the effect of a 12-week customized balance exercise program on LOS for community-dwelling older women with poor balance ability. Twenty-four older women with poor balance (composite maximum excursion [MXEcomp] score of less than 70% based on Limits of Stability) were divided into an exercise group and control group. After 12 weeks of balance exercises, mean MXEcomp improved (p < .05) from 58.6% to 79.0% in the exercise group. EPEcomp (composite endpoint excursion), RTcomp (composite reaction time), SVcomp3 (composite sway velocity on thick foam with the eyes open), UG (up and go) also improved, but the functional reach and other static balance indexes did not change. These results indicated that balance training allows older adults with poor balance to improve dynamic balance ability and potentially reduce risk for falls. 相似文献
19.
We consider the problem of constructing a fixed-size confidence region for the difference of means of two multivariate normal populations It is assumed that the variance-covariance matrices of two populations are different only by unknown scalar multipliers Two-stage procedures are presented to derive such a confidence region We also discuss the asymptotic efficiency of the procedure. 相似文献
20.
Makoto Ohta 《商业与经济统计学杂志》2013,31(4):521-528
Hedonic price indexes are estimated for U.S. used passenger cars for 1970–1983. A few notions of indexes that differ in the treatments of the expected present value of gasoline cost for driving a car over its remaining life are considered. Their relationships are obtained theoretically and examined empirically. Our indexes also are compared with the Consumer Price Index. 相似文献