Genetic variance and covariance patterns of larval development in the small white butterflyPieris rapae crucivora Boisduval

Summary Quantitative genetic theory indicates that genetic covariance patterns among life history characters should have played an important role as genetic constraint in life history evolution. Highly positve (and negative) genetic correlations between larval development time (or larval growth rate) and adult size characters were detected by means of sib analysis for the small white butterflyPieris rapae crucivora. The genetic associations suggested that evolution of developmental characteristics and adult phenotypic traits were constrained by pleiotropy. The positive genetic correlations between development time and adult body size may be compatible with the trade-off between them, but the negative genetic correlations between larval growth rate and adult body size are not predicted from theories of optimal energy allocation. That phenotypic correlations drastically differed from the genetic correlations indicates limitations of evolutionary inferences based only on phenotypic variation.     

Standardization as a Means for Globalizing a Commodity: The Case of Rapeseed in China*

Abstract Not all commodities are things, nor are all things available in society commodities. Then, what are commodities? Using the case of rapeseed and its products in China, this paper examines the role of grades and standards (G&S) in simultaneously determining the life of things as commodities and the position of humans as market participants. In the first section, we summarize our conceptual understandings of commodities. Next, the paper examines tests and trials to which rapeseed in China were subjected by the mid 1990s. We then discuss how G&S represent political processes among commodity chain actors for creating, legitimizing and maintaining the social relations between things and people. Lastly, we discuss our conclusion that the analysis of tests and trials helps us understand the process of commodification as simultaneous transformations of humans and things in a commodity chain while reorganizing linkages among these actors.     

Theoretical aspects of extinction by inbreeding depression

Populational extinction due to inbreeding depression is analyzed with simple population genetic and population ecological models. Two alternative genetic mechanisms of inbreeding depression, i.e. recessive deleterious genes and overdominant genes, are assumed in separate analyses in order to examine their relative importance. With both mechanisms the population size and the coefficient of inbreeding are maintained at stable equilibria if there is no non-genetic demographic disturbance or stress. With a certain amount of demographic disturbance the population declines rapidly due to interaction between the decrease of population size and the increase of inbreeding coefficient. Such rapid extinction occurs with both genetic mechanisms. However, in the case of overdominant genes extinction happens only if the equilibrium population size is small and the selection coefficient is large such that segregation load is large. In nature, extinction due to overdominant genes is considered to be much less likely than extinction due to recessive deleterious genes.     

Population dynamics of the Smith's red-backed vole in highlands of Shikoku

Summary and Conclusion Population dynamics of theSmith's red-backed vole predominantly common through uplands of Shikoku have been in some degree disclosed by the use of my own and Government Forest Station's samples collected since 1955 onward. It has proved that the upper-range population reaches its density peak possibly in late summer or early fall, but the lower-range one does probably in October–November as the seasonal trend in usual years. The upper one produced a peak three times at 3–4 year intervals, the first peak being an outbreak followed by a crash, during the last decade. It seems likely that all the populations through the range have, in the gross, fluctuated in phase after 1959 at least. The cyclic fluctuation may readily be explained by the theory of intrinsic mechanism, because no external factors are considered to have exerted a conclusive effect. Except what was concerned in the outbreak, the role of the social stress could be set at naught. The regulation of fecundiy by density was expressed more markedly in litter size and less in active reproductivity rate and incidence of pregnancy. The mean litter size at term as small as 2.00 is contrary to our expectation in view of the supposed prolific potential, nevertheless the observed frequency of litter poduction and intra-uterine survival rate has proved not to be so high as to make up for the small litter size. The problem in the postnatal mortality has remained to be solved.     

Dutasteride improves bone mineral density in male patients with lower urinary tract symptoms and prostatic enlargement: a preliminary study

Introduction: We studied the effect of dutasteride on bone mineral density (BMD) in aging male patients with lower urinary tract symptoms (LUTS) and prostatic enlargement.

Methods: We prospectively studied 17 patients with LUTS and prostatic enlargement. Before and 1 year after dutasteride (0.5?mg daily), we assessed International Prostate Symptom Score (IPSS), prostatic volume (PV), serum prostatic-specific antigen (PSA) and testosterone. BMD in the lumbar and femur was measured by DEXA method.

Results: Dutasteride significantly reduced PV (from 51?±?24 to 34?±?17?ml, p?p?p?2, p?2, p?2, p?Conclusions: Dutasteride has a potential to improve BMD with elevation of serum testosterone in aging male patients with LUTS and prostatic enlargement.     

EFFECTS OF PARENTAL LEAVE AND WORK HOURS ON FATHERS’ INVOLVEMENT WITH THEIR BABIES

Using data from the first wave of the Millennium Cohort Study, covering a large birth cohort of children in the UK at age 8 to 12 months, this paper examines the effects of leave-taking and work hours on fathers’ involvement in four specific types of activities: being the main caregiver; changing diapers; feeding the baby; and getting up during the night. We also investigate the effects of policies on fathers’ leave-taking and work hours. We find that taking leave and working shorter hours are related to fathers being more involved with the baby, and that policies affect both these aspects of fathers’ employment behaviour. Thus, we conclude that policies that provide parental leave or shorter work hours could increase fathers’ involvement with their young children.     

On the Admissibility of Linear Estimators in a Multivariate Normal Distribution Under LINEX Loss Function

Consider an estimation problem of a linear combination of population means in a multivariate normal distribution under LINEX loss function. Necessary and sufficient conditions for linear estimators to be admissible are given. Further, it is shown that the result is an extension of the quadratic loss case as well as the univariate normal case.     

Sensitivity analysis in maximum likelihood factor analysis

The present paper deals with sensitivity analysis in maximum likelihood factor analysis. To investigate the influence of a small change of data we derive theoretical influence functions I(x; LL^T ) and I(x; Δ) for a common variance matrix T= LL^T and a unique variance matrix Δ respectively. Numerical examples are shown to illustrate our procedure.     

Sensitivity analysis in principal component analysis:influence on the subspace spanned by principal components.

The problem of detecting influential observations in principalcomponent analysis was discussed by several authors. Radhakrishnan and kshirsagar ( 1981 ), Critchley ( 1985 ), jolliffe ( 1986 )among others discussed this topicby using the influence functions I(X;θ_s)and I(X;V_s)of eigenvalues and eigenvectors, which wwere derived under the assumption that the eigenvalues of interest were simple. In this paper we propose the influence functionsI(X;∑^q _s=1θ_sV_sV_s ^T)and I(x;∑^q _s=1V_sV_s ^t)(q<p;p:number of variables) to investigate the influence onthe subspace spanned by principal components. These influence functions are applicable not only to the case where the edigenvalues of interst are all simple but also to the case where there are some multiple eigenvalues among those of interest.