Regional Income Inequality in the Post-War Japan

In his seminal work on national development and regional inequality, Williamson (1965) predicts that regional income inequality will pass through three distinct phases as a nation moves through the early development stages to maturity. In the early stages of economic development, regional income inequality will increase, largely because of the disequilibrating effects of factor mobility. This will be followed by a period of stability, characterized by a relatively high level of inequality between regions. Finally, a lessening of regional inequality will set in as the national economy matures and equilibrating forces take effect. This overall process, if plotted against national economic development, will result in a bell-shaped or inverted U-shapes curve. The early stages of development are also associated with rapid urbanization, though with a shift toward population dispersion as the economy matures. Other stylized facts in the process of development include industrialization, demographic transition, and changing inequality of income among population subgroups (Alonso, 1980). The concentration of population in and around large cities is usually accompanied by an increase in regional income inequality. Some researchers have argued that this population concentration and concurrent increase in regional inequality does not impede economic development, and may in fact favor it. Nonetheless, many national governments have introduced policies of balanced regional development. The main objective of this paper is to measure regional income inequality in the post-war Japan using Williamson?s weighted coefficient of variation. Based on prefectural population and GDP data, it investigates longer-term trends in regional income inequality. A sectoral decomposition analysis is also performed to examine the extent to which each industrial sector contributes to the overall weighted coefficient of variation. We hope to gain a deeper understanding of the relationship between national development, industrialization, and regional inequalities in the post-war Japan.

Activation of Biodefense System by Low-Dose Irradiation or Radon Inhalation and Its Applicable Possibility for Treatment of Diabetes and Hepatopathy

Adequate oxygen stress induced by low-dose irradiation activates biodefense system, such as induction of the synthesis of superoxide dismutase (SOD) and glutathione peroxidase. We studied the possibility for alleviation of oxidative damage, such as diabetes and nonalcoholic liver disease. Results show that low-dose γ-irradiation increases SOD activity and protects against alloxan diabetes. Prior or post-low-dose X- or γ-irradiation increases antioxidative functions in livers and inhibits ferric nitrilotriacetate and carbon tetrachloride-induced (CCl4) hepatopathy. Moreover, radon inhalation also inhibits CCl4-induced hepatopathy. It is highly possible that low-dose irradiation including radon inhalation activates the biodefence systems and, therefore, contributes to preventing or reducing reactive oxygen species-related diabetes and nonalcoholic liver disease, which are thought to involve peroxidation

Probing the Temperature Structure of the Inner Region of a Protoplanetary Disk

Midplane heating induced by disk accretion plays a key role in determining the disk temperature particularly at the inner disk midplane where planets form. However, the efficiency of accretion heating has been not well constrained by observations. We construct two-dimensional models of the Class II disk around CW Tau, taking into account the midplane heating. The models are compared with the ALMA dust continuum observations at Bands 4, 6, 7 and 8, with an angular resolution of 0.1 arcsec. The observed brightness temperatures are almost wavelength-indenpendent at $\lesssim$10 au. We find that if the maximum dust size $a_{\rm max}$ is $\lesssim100~{\rm \mu m}$, the brightness temperatures predicted by the model exceed the observed values, regardless of the efficiency of accretion heating. The low observed brightness temperatures can be explained if millimeter scattering reduces the intensity. If the disk is passive, $a_{\rm max}$ needs to be either $\sim150~{\rm \mu m}$ or $\gtrsim$ few ${\rm cm}$. The accretion heating significantly increases the brightness temperature particularly when $a_{\rm max}\lesssim300~{\rm \mu m}$, and hence $a_{\rm max}$ needs to be either $\sim300~{\rm \mu m}$ or $\gtrsim$ few ${\rm cm}$. The midplane temperature is expected to be $\sim$1.5-3 times higher than the observed brightness temperatures, depending on the models. The dust settling effectively increases the temperature of the dust responsible for the millimeter emission in the active disk, which makes the model with $300~{\rm \mu m}$-sized dust overpredicts the brightness temperatures when strong turbulence is absent. Porous dust (porosity of 0.9) makes the accretion heating more efficient so that some sort of reduction in accretion heating is required. Future longer wavelength and higher angular resolution observations will help us constrain the heating mechanisms of the inner protoplanetary disks.Comment: 19 pages, 25 figures, accepted for publication in A&

Inhibitory Effects of Pretreatment with Radon on Acute Alcohol-Induced Hepatopathy in Mice

We previously reported that radon inhalation activates antioxidative functions in the liver and inhibits carbon tetrachloride-induced hepatopathy in mice. In addition, it has been reported that reactive oxygen species contribute to alcohol-induced hepatopathy. In this study, we examined the inhibitory effects of radon inhalation on acute alcohol- induced hepatopathy in mice. C57BL/6J mice were subjected to intraperitoneal injection of 50% alcohol (5 g/kg bodyweight) after inhaling approximately 4000 Bq/m(3) radon for 24 h. Alcohol administration significantly increased the activities of glutamic oxaloacetic transaminase (GOT), glutamic pyruvic transaminase (GPT) in serum, and the levels of triglyceride and lipid peroxide in the liver, suggesting acute alcohol- induced hepatopathy. Radon inhalation activated antioxidative functions in the liver. Furthermore, pretreatment with radon inhibited the depression of hepatic functions and antioxidative functions. These findings suggested that radon inhalation activated antioxidative functions in the liver and inhibited acute alcohol- induced hepatopathy in mice

Inhibitory Effects of Prior Low-dose X-irradiation on Cold-induced Brain Injury in Mouse

We examined the inhibitory effects of low-dose X-irradiation on mouse brain tissue with cold-induced injury by comparing tissue samples from three groups of mice: control, sham-irradiated cold-exposed, and X-ray-irradiated (0.5 Gy) cold-exposed mice. The water content in brain increased significantly in the sham-irradiated group following the cold-induced injury relative to the control group. However, water content in brain tissue from the X-ray-irradiated group was significantly lower than that from the sham-irradiated group. Levels of antioxidants, such as superoxide dismutase and glutathione, in brain tissue from the X-ray-irradiated group were higher than those from the sham-irradiated group. Moreover, the cold injury-induced cell death, particularly apoptosis, while low-dose irradiation inhibited cell death, especially among glial cells, but not numeral cells. These findings suggest that prior low-dose X-irradiation activated antioxidant function and inhibited cold-induced brain injury

An Assessment of Radioactivity Levels of 210Pb and 40K in Tobacco and Radiation Exposure from Smoking

No research has been conducted on the radiation influence of tobacco on the alimentary system, although there have been some previous works on the respiratory system. In this study, the radioactive concentrations of 210Pb and 40K in a cigarette sample were first measured. The transfer factors of the nuclides from tobacco into smoke and solution (saliva and/or alcohol) were then examined. Moreover, the radiation doses from smoke inhalation were also evaluated. The radioactive concentrations of 210Pb and 40K in the cigarette tobacco were 0.01 and 0.3 Bq/cigarette. Since this 210Pb activity and the 210Po activity previously reported for the same sample were comparable, it can be concluded that there was a radioactive equilibrium between the 2 nuclides. The observed transfer factor of 210Pb (12%) into smoke was almost the same as that of 40K (15%), whereas the reported value for 210Po (60%) was significantly higher. The radiation doses due to inhalation of cigarette smoke varied from organ to organ, depending on the organotropic properties of the nuclide. For example, the kidneys, respiratory tract, and spleen showed relatively high doses from 210Pb and 210Po. The leaching rates indicated an inconsistent tendency related to solution types. This result could suggest that alcohol drinking, which is common in smokers, does not especially enhance the leaching characteristics