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1.
Kenichi Ozaki 《Researches on Population Ecology》1993,35(2):273-284
Summary The number of larvae reaching maturity within the gall ofAdelges japonicus was positively related to gall volume, and the relationship between the number of mature larvae and gall volume did not change
with different densities of colonized larvae.
The population changes in the bud galls ofA. japonicus were surveyed by collecting the galls, which did not suffer predation or parasitism within the galls, from young artificial
plantations ofPicea jezoensis over two years. In the year when the density of colonized larvae was high, they suffered a 42% mortality within the galls,
whereas mortality was nearly zero in the low density year. The numbers of larvae per gall were positively correlated with
gall volume. The regression lines of the number of colonized larvae on gall volume did not differ significantly in the regression
coefficients between the two years, whereas the intercept was significantly higher in the year when the density of colonized
larvae was higher. However, different within-gall mortality nullified this difference, and the regression lines of the number
of mature larvae on gall volume had no significant difference both in the regression coefficients and the intercepts. This
suggests that the number of mature larvae per gall was limited by available resources within the gall which were positively
related to gall volume. In 25% of the galls in which mature larvae inhabited, the space within the galls were completely filled
by the larvae, indicating that space was one of the limiting resources. Gall volume also affected the number of adults that
emerged from the gall and the potential number of their progeny. 相似文献
2.
3.
The deme formation hypothesis in herbivorous insects states that herbivores differentiate genetically into small demes, each
specialized in the idiosyncratic traits of individual plants. We examined this hypothesis in gall-forming aphids,Adelges japonicus, by reciprocal transfers of aphids among three susceptible clones ofPicea jezoensis standing in proximity. Performance of aphids transferred to their natal clone was compared with that of aphids transferred
to other novel clones. ANCOVA showed no significant donor (source of aphids) by receptor (recipient of aphids) interactions
for both total aphid performance on the host tree over a life cycle and its three subdivisions(q
1,q
2 andq
3). In addition, the total performance on the natal clone was lowest among those in the three clones, which was explicitly
against the prediction from the local adaptation. In contrast, there were significant receptor effects onq
1 (fecundity of gallicolae multiplied by survivorship of fundatrices while feeding on needles) andq
3 (fecundity of fundatrices multiplied by survivorship of gallicolae before emergence from the galls), suggesting genetic differences
in resistance among clones. The two-fold difference inq
3 among clones was due to different gall size, which was highly correlated with the number of gallicolae that emerged from
the gall. The two-fold difference inq
1 seemed to be caused by different survivorship of larval fundatrices while feeding on needles. 相似文献
4.
Kenichi Kawasaki 《International Journal of Japanese Sociology》2004,13(1):22-35
Abstract: Singapore had been called a Cultural Desert since its independence in 1965, but from the beginning of 1990s, there has been a significant change. The Singapore Government started to call their city a “Global City for the Arts”, making numerous cultural policy changes. They also worked on various cultural experiments to establish their cultural leadership or hegemony among Association of South East Asian Nations (ASEAN) countries. The development of arts policies, cultural industries and people's positive commitment towards cultural exchanges are examples of this change. Singapore therefore is now playing the role of the cultural hub among the ASEAN countries. As an example of this, the present study discusses “Esplanade”, which opened as a huge cultural complex in October 2002. Then the paper will also discuss both bright and dark sides of the cultural development in Singapore. As a conclusion, this paper discusses the possibility of the cultural contribution of Singapore to ASEAN countries, in spite of having serious epistemological discontinuity among ASEAN. 相似文献
5.
Akiko Uchida Richard G. Bribiescas Peter T. Ellison Masao Kanamori Juko Ando Nobuyoshi Hirose 《The aging male》2013,16(4):207-213
Objective. We examined age associated variation in salivary testosterone values among Japanese males as well as anthropometric measurements.Methods. Salivary samples were collected in pretreated sodium azide treated tubes. The first series: 15–79-year-old males (n = 99); two morning and two evening samples were collected at home for two days. The second series: 90-year-old males (n = 29); one morning sample was collected. Testosterone values were determined using an iodine125-based radioimmunoassay kit modified for saliva.Results. Results show 1) a significant decrease in salivary testosterone values from 20s to 40s and older, 2) no significant decline after 40 through 90 years old, 3) no significant age-related differences in the degree of intraindividual diurnal fluctuation across age groups of 40–70s, and 4) higher BMI is associated with the lower salivary testosterone among 40–70s.Conclusions. These results suggest that neither a constant decrease of salivary testosterone values or markedly reduced intraindividual fluctations are universal aspects of aging. Older males may maintain relatively high testosterone levels compared to younger men and a relatively ‘robust’ neuroendocrinological system. 相似文献
6.
This paper discusses the results of a time budget survey which was conducted nationwide in Japan in 1995 on ‘information behavior’, that is, the amount of time people spent communicating and using information media ranging from conversations to computers. We propose a three-dimensional time budget survey as a method for measuring information behavior in actual life. The method classifies information behavior into 24 categories and measures them with respect to three factors, i.e. time, location and purpose of behavior. Our survey revealed that the total time spent on information behavior was about seven hours per day, of which about 45% was spent watching TV. The displacement effect of PC use on TV watching was estimated by a “time-shift matching” design. The results demonstrated that use of a PC does not significantly affect TV viewing, despite a large difference in TV viewing time between PC users and non-users. 相似文献
7.
This paper proposes a new treatment for electrical insulation degradation. Some types of insulation which have been used under
various circumstances are considered to degrade at various rates in accordance with their stress circumstances. The cross-linked
polyethylene (XLPE) insulated cables inspected by major Japanese electric companies clearly indicate such phenomena. By assuming
that the inspected specimen is sampled from one of the clustered groups, a mixed degradation model can be constructed. Since
the degradation of the insulation under common circumstances is considered to follow a Weibull distribution, a mixture model
and a Weibull power law can be combined. This is called The mixture Weibull power law model. By using the maximum likelihood
estimation for the newly proposed model to Japanese 22 and 33kV insulation class cables, they are clustered into a certain
number of groups by using the AIC and the generalized likelihood ratio test method. The reliability of the cables at specified
years are assessed.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
8.
When we perceive the emotions of other people, we extract much information from the face. The present experiment used FACS (Facial Action Coding System), which is an instrument that measures the magnitude of facial action from a neutral face to a changed, emotional face. Japanese undergraduates judged the emotion in pictures of 66 static Japanese male faces (11 static pictures for each of six basic expressions: happiness, surprise, fear, anger, sadness, and disgust), ranging from neutral faces to maximally expressed emotions. The stimuli had previously been scored with FACS and were presented in random order. A high correlation between the subjects' judgments of facial expressions and the FACS scores was found. 相似文献
9.
Kemmawadee Preedalikit Ivy Liu Yuichi Hirose Nokuthaba Sibanda Daniel Fernández 《Australian & New Zealand Journal of Statistics》2016,58(2):153-172
Medical research frequently focuses on the relationship between quality of life (QoL) and survival time of subjects. QoL may be one of the most important factors that could be used to predict survival, making it worth identifying factors that jointly affect survival and QoL. We propose a semiparametric joint model that consists of item response and survival components, where these two components are linked through latent variables. Several popular ordinal models are considered and compared in the item response component, while the Cox proportional hazards model is used in the survival component. We estimate the baseline hazard function and model parameters simultaneously, through a profile likelihood approach. We illustrate the method using an example from a clinical study. 相似文献
10.
The growth curve model has been developed for longitudinal data, and its time trend is usually described by polynomials. However, it is difficult to interpret each coefficient of the polynomials with higher degrees, even when the number of repetitions is sufficiently large. We propose herein an alternative growth curve model having time-varying coefficients. 相似文献