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We conducted array measurements of vertical mictrotremors to determine an S-wave velocity structure in Tokyo Metropolitan coastal area in the center of the Kanto district, Japan, for evaluating characteristics of long-period ground motions. Phase velocities of Rayleigh waves were estimated from F-K and SPAC analyses of the array data. We, next, inverted them to S-wave velocity structures of deep sediments from a genetic inversion using existing data on subsurface structure. Furthermore, we investigated characteristics of several earthquake records during shallow earthquakes in the seismic array in the area. Phase velocities of fundamental Love waves and fundamental and first-higher mode Rayleigh waves in a period range from 2 to 7 seconds were determined from semblance analyses of the earthquake array data. The final S-wave profile was selected among the profiles discussed in the microtremor exploration from the constrained condition given from the phase velocities estimated from the earthquake observation. We also discussed on the propagation directions of the surface waves in the earthquake records.

本研究は,北海道渡島支庁管内のワルイ川およびポンワルイ川で実施する河川改修において,実験的管理を採用し,キュウリウオの産卵場所および魚類の生息場所を調査し,魚類の生態特性からみた作業仮説を設定することを目的とした.調査は2000年5月から6月にかけて,工事施工箇所を中心に設定した調査区(上流区,工事区,中流区および下流区)で行い,キュウリウオ着床卵の密度,死亡率および魚類の生息密度と物理環境との関係を解析した.解析の結果,キュウリウオの産卵場所は主に工事区より下流域に位置すること,各生息魚類が様々なハビタットタイプを選択し(例えば,サクラマスはカバーを有する淵に選択性を有する等),工事区を含み河口から上流区まで広く分布すること,カンキョウカジカ,エゾハナカジカ等遊泳力の小さい両側回遊魚の生息密度は上流に移行するにつれて低下することが明らかとなった.さらに,キュウリウオ着床卵の密度および死亡率は主に河畔林によって構成されるカバー率に規定されており,カバー率が低下すると河床表面に付着藻類が繁茂し,流下してくる受精卵および細粒土砂を貯留し,死亡率を増大させる相互関係が考えられた.以上を勘案し,魚類への影響を極力回避するために次に示す2つの作業仮説を設定した.仮説-1:「工事区において河床勾配を低減し,水の勢いを制御すれば,工事区より上流への魚類の遡上が確保され,下流域においてもキュウリウオの産卵場所および両側回遊魚の生息地が保全される.」仮説-2:「工事区の河畔林カバーを早期に回復させれば,キュウリウオの卵の死亡率が抑制され,適度な蛇行河道により淵が形成されれば,サクラマスおよび他の魚種の生息地が創出される.」

Genetic trade-offs in host plant use are thought to promote the evolution of host specificity. Experiments on a range of herbivorous insects, however, have found negative genetic correlation in host plant use in only a limited number of species. To account for the general lack of negative genetic correlation, recent hypotheses advocate that different stages in evolution of host use must be distinguished: initial performance on a novel host in comparison with the established host, and performance on both hosts after the insect population has interacted with both hosts for a long time. The hypotheses suggest that genetic correlation may not necessarily be negative at the initial stage. The present study examines growth performance on both the established and a novel host in a herbivorous ladybird beetle, Epilachna vigintioctomaculata Motschulsky (Coccinellidae, Epilachninae). The results show that traits of growth performance across hosts were positively or neutrally correlated, but there was no evidence of a negative genetic correlation. In addition, significant genetic variance of growth performance on each host was detected, suggesting that E. vigintioctomaculata can potentially respond to selection for increased performance on both plant species. These results and similar results from experiments on other herbivores suggest that host expansion may not be constrained genetically, at least at the initial stage of host range evolution.

The causes and timing of seed death in early regeneration process of Siebold's beech (Fagus crenata Blume) was studied at 15 sites along a snowfall gradient in Japan, in order to clarify why the seedling density of the species has geographic difference remarkably. Seed production did not significantly differ along the snowfall gradient. Pre-dispersal seed mortality by insect damage was higher at sites with light snowfall than at sites with heavy snowfall, but this only seemed to be a minor factor influencing the population. A large proportion of the viable nuts that fall in autumn ware killed in winter before germination. Winter mortality was much higher at sites with thin snow cover than that at sites with thick snow cover, and this factor was strongly correlated with the geographic variation of seedling regeneration probability. There was little seed mortality by winter desiccation. The main factor contributing to the geographic difference seemed to be a seed predation by rodents in winter. Deep snow cover may reduce the success of rodents finding seeds in winter. Thus the observed relationship between snowpack depth and early mortality may be due to an indirect effect through the process of seed predation.p>

1. The present study was designed to test the hypothesis that beneficial effects of angiotensin converting enzyme (ACE)inhibitors are independent of a fall in blood pressure in rat experimental heart failure following coronary ligation. 2. The animals were assigned randomly to six groups; sham operation, controls subjected to coronary ligation (control), coronary ligation plus chronic treatment with ACE inhibitors at non- and hypotensive doses; perindopril (0.2 or 2 mg kg-1 day-1) or enalapril (2 or 20 mg kg-1 day-1) for three weeks starting one week after the ligation. 3. Systemic blood pressure was measured every week during the experiments. At the end of the treatments, cardiac function and heart weight (an index of myocardial hypertrophy) were determined. In the other animals, ACE activities in plasma and tissues including heart, kidney, lung and blood vessels were measured. 4. In the controls, cardiac ACE activity, weight of right ventricle and left ventricular end-diastolic pressure (LVEDP) were higher compared to those in the sham-operated animals four weeks after the coronary ligation. However, ACE activities were not changed in plasma, kidney, lung and aorta by ligation of the coronary artery. 5. The chronic treatment with perindopril at a dose of 0.2 mg kg-1 day-1 inhibited the increase in ACE activity in cardiac tissue and suppressed the right ventricular hypertrophy without affecting systemic haemodynamics. In contrast, enalapril at a dose of 20 mg kg-1 day-1, but not 2 mg kg-1 day-1, prevented the development of the right ventricular hypertrophy. Enalapril at 20 mg kg-1 day-1 also lowered systemic blood pressure. 6. There is no significant correlation between systemic blood pressure and right ventricular hypertrophy at the end of the treatment with perindopril (r = 0.06) or enalapril (r = 0.1).7. These findings demonstrate that perindopril, an ACE inhibitor, prevents cardiac hypertrophy without affecting systemic blood pressure in the rat with heart failure after coronary ligation, and suggest that selective augmentation of ACE activity in cardiac tissue is involved in the progression of hypertrophy in this model.

This paper presents a 3D laser scanner that can gaze at an arbitrary region. By modulating the secondary rotation speed of roundly swinging 3D laser scanner, it gazes at a specific region and measures with high density measurement points. The proposed method uses a secondary rotation motor to control the measurement point density and no extra motor is required. The 3D scanner can keep the field of view of and scan cycle time while gazing at any region. The system is evaluated on experimental targets for different scenarios using a mobile robot.

This paper proposes a new localization method for outdoor navigation using a stereo camera only. Vision-based navigation in outdoor environments is still challenging because of large illumination changes. To cope with various illumination conditions, we use 2D occupancy grid maps generated from 3D point clouds obtained by a stereo camera. Furthermore, we incorporate salient line segments extracted from the ground into the grid maps. This grid map building is not much affected by illumination conditions. On the grid maps, the robot poses are estimated using a particle filter that combines visual odometry and map-matching. Experimental results showed the effectiveness and robustness of the proposed method under various weather and illumination conditions.

This paper proposes a light-weight sensor platform that consists of gyro-assisted odometry and a 3D laser scanner for localization of human-scale robots. The gyro-assisted odometry provides highly accurate positioning only by dead-reckoning. The 3D laser scanner has a wide field of view and uniform measuring-point distribution. Robust and computationally inexpensive localization is implemented on the sensor platform using a particle filter on a 2D grid map generated by projecting 3D points on to the ground. The system uses small and low-cost sensors, and can be applied to a variety of mobile robots in human-scale environments. Outdoor navigation experiments were performed at the Tsukuba Challenge 2009, which is an open proving ground for human-scale robots. Our robot successfully navigated the assigned 1-km course in a fully autonomous mode multiple times.

Spontaneously hypertensive rats (SHR) were injected with streptozotocin (STZ-SHR) to induce diabetes. The effect of DP-1904, a thromboxane A2 synthetase inhibitor, on diabetic nephropathy was then studied by administering it for 5 months (1 or 10 mg/kg). DP-1904 did not affect renal 6-keto prostaglandin (PG)F1 alpha production in STZ-SHR, but markedly inhibited renal thromboxane (TX) B2 production, so that the 6-keto PGF1 alpha/TXB2 ratio was significantly increased (P less than 0.05). STZ-SHR showed significant uraemia and proteinuria, plus increases in urinary gamma-glutamyl-transpeptidase and urinary N-acetyl-beta-glucosaminidase. DP-1904 significantly decreased (P less than 0.01) the urinary changes. STZ-SHR also showed an increase in mesangial periodic acid-Schiff-positive substance and in relative renal weight, both of which were significantly inhibited by DP-1904 (P less than 0.05). Thus, DP-1904 inhibited both TXB2 production and the progression of renal damage in STZ-SHR.

The effects of DP-1904, a thromboxane (TX) A2 synthase inhibitor, on renal function were investigated by analysis of prostanoid metabolism in hydronephrotic and ischemic rat kidney models, and in isolated perfused normal and hydronephrotic rat kidneys. The increase in production of TXB2 in hydronephrotic or ischemic kidneys was significantly suppressed by intraperitoneal DP-1904 (10 mg/kg), with the 6-keto-prostaglandin F1 alpha to TXB2 ratio being significant increased. Urine volume, glomerular filtration rate and renal plasma flow were all improved. DP-1904 (0.3 micrograms/min) blocked the effects of infused arachidonic acid on isolated perfused normal rat kidneys thus reducing TXB2 levels and perfusion pressure but the pressor response to norepinephrine or angiotensin II remained unchanged. In isolated perfused hydronephrotic rat kidneys, DP-1904 suppressed the increase in perfusion pressure and TXB2 production caused by platelet-activating factor. These findings suggested that DP-1904 improved renal failure by specifically inhibiting TXA2 production.

A series of semi-rigid analogs of phenethylamine was prepared as fixed transoid and cisoid analogs of mebeverine, and tested for spasmolytic activity in vitro. The fixed transoid analogs were more potent than the corresponding cisoid analogs. In this series, tetrahydro-2-napthylamine derivative (2a) which is presumed to take transoid conformation had the most potent activity, and tetrahydroisoquinoline derivatives (2g and 2h) which are presumed to take typical cisoid conformations were less active. These results suggested that the phenethylamine moiety of mebeverine takes the transoid conformation for the manifestation of the spasmolytic activity.

N-[(Benzoyloxy)alkyl]-1,2,3,4-tetrahydro-2-naphthylamine derivatives were synthesized from 1,2,3,4-tetrahydro-2-naphthylamines and evaluated for their spasmolytic. Some of these compounds showed a nerve-selective effect on colon rather than stomach in anesthetized dogs and were found to be equal to or more active than the reference drug (mebeverine). The biological data have indicated some structure-activity relationships. Among these compounds, N-ethyl-N-[6-(3,4-dimethoxybenzoyl)oxy]hexyl]-1,2,3,4-tetrahydro-6-methoxy-2- napththylamine hydrochloride (63) was found to be the most active spasmolytic agent.

N-[(Benzoyloxy)alkyl]-1,2,3,4-tetrahydro-2-naphthylamine derivatives were synthesized from 1,2,3,4-tetrahydro-2-naphthylamines and evaluated for their spasmolytic. Some of these compounds showed a nerve-selective effect on colon rather than stomach in anesthetized dogs and were found to be equal to or more active than the reference drug (mebeverine). The biological data have indicated some structure-activity relationships. Among these compounds, N-ethyl-N-[6-(3,4-dimethoxybenzoyl)oxy]hexyl]-1,2,3,4-tetrahydro-6-methoxy-2- napththylamine hydrochloride (63) was found to be the most active spasmolytic agent.