An economic value for ecosystem-based disaster risk reduction using paddy fields in the kasumitei open levee system

Paddy and Water Environment - In this article, we examined the value of the traditional Japanese flood control measure that uses a discontinuous levee (kasumitei). By avoiding the use of...     

A New Approach for Characterization of Single Raindrops

To determine the characteristics of single raindrops as a function of their size, the collodion film method was newly applied to the sampling of single raindrops. Sampling of single raindrops was performed at a height of 20 m above ground level of the Kyoto University building located in Uji, Japan during rain events from September to November 1999. It was possible to get successfully replicas of raindrop by collodion film method. And we tried to analyze the elemental components of the nuclei and pollutants that were incorporated into the developing raindrop. To the analysis of single raindrops, Particle Induced X-ray Emission (PIXE) was applied. Several elements including S in single raindrops were detected by PIXE. The concentrations of every element increased with decreasing drop diameter. Furthermore, to acquire more detailed information such as inner-structure and mixing state in single raindrops, micro-PIXE analysis was performed. The nucleation centers of single raindrops were successfully analyzed by micro-PIXE. Ca, S and Fe were apparently detected by scanning beam of 1 ～ 2 µm diameter and about 70 pA beam current.     

Discovery of a Jupiter/Saturn analog with gravitational microlensing

Searches for extrasolar planets have uncovered an astonishing diversity of planetary systems, yet the frequency of solar system analogs remains unknown. The gravitational microlensing planet search method is potentially sensitive to multiple-planet systems containing analogs of all the solar system planets except Mercury. We report the detection of a multiple-planet system with microlensing. We identify two planets with masses of approximately 0.71 and approximately 0.27 times the mass of Jupiter and orbital separations of approximately 2.3 and approximately 4.6 astronomical units orbiting a primary star of mass approximately 0.50 solar mass at a distance of approximately 1.5 kiloparsecs. This system resembles a scaled version of our solar system in that the mass ratio, separation ratio, and equilibrium temperatures of the planets are similar to those of Jupiter and Saturn. These planets could not have been detected with other techniques; their discovery from only six confirmed microlensing planet detections suggests that solar system analogs may be common.     

High-density electron anions in a nanoporous single crystal: [Ca24Al28O64]4+(4e-)

We removed approximately 100% of clathrated oxygen ions from the crystallographic cages in a single crystal of 12CaO.7Al2O3, leading to the formation of high-density (approximately 2 x 10(21) cm-3) electrons highly localized in the cages. The resulting electron forms a structure that we interpret as an F+ center and migrates throughout the crystal by hopping to a neighboring cage with conductivity approximately 100 siemens per centimeter, demonstrating that the encaged electron behaves as an anion. The electron anions couple antiferromagnetically with each other, forming a diamagnetic pair or singlet bipolaron. The resulting [Ca24Al28O64]4+(4e-) may be regarded as a thermally and chemically stable single crystalline "electride."     

Anxiety change through electroencephalographic alpha feedback seen only in high anxiety subjects

Subjects who were either high or low in trait anxiety used alpha feedback to increase and to decrease their electroencephalographic alpha activity. The alpha changes were tightly linked to anxiety changes, but only in high anxiety subjects (for whom anxiety was reduced in proportion to alpha increases, and was increased in proportion to alpha suppression). Low trait-anxiety subjects were superior at both enhancement and suppression training, but their alpha changes were not related to anxiety changes. In both groups, anxiety changes were generally unrelated to either resting levels or changes in frontalis electromyograms and respiration rate. These results suggest that long-term alpha feedback training (at least 5 hours) may be useful in anxiety therapy.     

The effect of radiation on the viability and migratory ability of second-stage larvae of Toxocara canis in mice

Larval counts were made on mice 2 days after oral inoculation with X-ray (0-320 Krad) or of gamma ray (0-6 Mrad) irradiated eggs containing second-stage Toxocara canis larvae. The majority of the larvae irradiated with 0-40 Krad were recovered from the liver and lungs, while most of the larvae irradiated with 80 or 160 Krad remained in the digestive tract, mainly in the stomach and the proximal half of the small intestine. Only a small number of the 320 Krad irradiated larvae was recovered from the mice. No significant difference was observed in the viability of irradiated larvae incubated in vitro up to 13 days after irradiation. However, a substantial percentage of the 160 and 320 Krad-irradiated larvae hatched during that period. Very few larvae were recovered from the digestive tract of mice inoculated with eggs irradiated with 0.5 Mrad, and only one and four larvae were recovered from the liver and lungs of a mouse. No visceral larval migration was observed in mice inoculated with 1 Mrad-irradiated eggs. The minimum lethal radiation dose for second-stage T. canis larvae in eggs is proposed to be 1 Mrad.     

Effect of pregnancy on gravid sclerosis of bovine uterine arteries

Gravid sclerosis of the uterine artery was histologically examined in multiparous cows. This sclerosis was characterized by a thickening of the intima and a lamination of the internal elastic lamina. It was clearly observed at non-pregnant and early-pregnant stages and in the late postpartum period, but it could not be detected at term-pregnant stages and in the early postpartum period. These results suggest that the gravid sclerosis disappears during pregnancy and re-establishes after parturition. The importance of local factors, e.g. hemodynamics, in the cyclic appearance of gravid sclerosis is discussed.