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We present ionized gas properties of nine local ultra/luminous infrared galaxies (U/LIRGs) at z < 0.04 through Integral Field Unit (IFU) observations with KOOLS-IFU on the Seimei Telescope. The observed targets are drawn from the Great Observatories All-sky LIRG Survey (GOALS), covering a wide range of merger stages. We successfully detect emission lines such as Hβ, [O iii]λ5007, Hα, [N ii]λλ6549, 6583, and [S ii]λλ6717, 6731 with a spectral resolution of R = 1500–2000, which provides (i) a spatially resolved (∼200–700 pc) moment map of ionized gas and (ii) diagnostics for an active galactic nucleus (AGN) within the central ∼3–11 kpc in diameter for our sample. We find that the [O iii] outflow that is expected to be driven by an AGN tends to be stronger (i) towards the galactic center and (ii) as a sequence of the merger stage. In particular, the outflow strength in the late-stage (stage D) mergers is about 1.5 times stronger than that in the early-state (stage B) mergers, which indicates that galaxy mergers could induce AGN-driven outflow and play an important role in the co-evolution of galaxies and supermassive black holes.

We conduct a hard X-ray to radio multiwavelength spectral energy distribution (SED) decomposition for 57 local luminous and ultraluminous infrared galaxies (U/LIRGs) observed with Nuclear Spectroscopic Telescope Array and/or Swift/Burst Alert Telescope in GOALS (Armus et al. 2009) sample. We modify the latest SED-fitting code X-CIGALE by implementing the infrared (IR) CLUMPY model, allowing the multiwavelength study with the X-ray torus model (XCLUMPY) self-consistently. Adopting the torus parameters obtained by the X-ray fitting (Yamada et al. 2021), we estimate the properties of host galaxies, active galactic nucleus (AGN) tori, and polar dust. The star formation rates (SFRs) become larger with merger stage and most of them are above the main sequence. The SFRs are correlated with radio luminosity, indicating starburst emission is dominant in the radio band. Although polar-dust extinction is much smaller than torus extinction, the UV-to-IR (mainly IR) polar dust luminosities are $\sim$2 times larger than the torus ones. The polar-dust temperature decreases while the physical size, estimated by the temperature and dust sublimation radius, increases with AGN luminosity from a few tens of parsec (early mergers) to kiloparsec scales (late mergers), where the polar dust is likely the expanding (i.e., evolving) dusty outflows. The comparison between SFRs and intrinsic AGN luminosities suggests that the starbursts occur first and AGNs arise later, and overall their growth rates follow the simultaneous coevolution relation that can establish the local galaxy-SMBH mass relation. We confirm the coexistence of intense starbursts, AGNs, and large-scale outflows in late mergers, supporting a standard AGN feedback scenario., 84 pages (5 tables/29 figures in the main text and 8 tables/18 figures in the Appendix), accepted in ApJS

Changes in body weight (BW), systolic blood pressure (SBP), and localization of renin in the kidneys of neonates born to normal mothers (C neonates) or to five-sixths (5/6) nephrectomized (2/3 left kidney and right kidney) mothers (Nx neonates) were studied. Maternal 5/6 nephrectomy caused weight loss in neonates but no differences in SBP or renin localization. Culling Nx neonates to a litter of 3 at 1 day after birth resulted in growth catching up with C neonates from 3 weeks old and increases in both SBP and renin-positive cells in neonatal kidney. These findings revealed that maternal 5/6 nephrectomy results in low-birth-weight neonates and that these neonates are at increased risk of metabolic syndrome by catch-up growth.

Introduction Sudden-onset quadriplegia is a neurologic emergency that requires immediate management. Anterior spinal artery syndrome (ASAS) is rare, but can cause sudden-onset quadriplegia. Magnetic resonance imaging (MRI) is an essential imaging modality for diagnosing ASAS. Case Presentation A 31-year-old woman without previous medical history was transferred to our facility for further workup of sudden-onset neck pain with quadriplegia. Diffusion-weighted imaging (DWI) revealed hyperintense signals predominantly in grey matter with a decreased apparent diffusion coefficient (ADC). These findings strongly suggested ASAS with spinal cord infarction. Edaravone, heparin, and aspirin with steroid pulse therapy were immediately initiated. Twelve days in an intensive care unit was required for dyspnea. Symptoms gradually resolved with rehabilitation, but the patient was wheelchair-bound without bladder control and was transferred to a rehabilitation facility on hospital day 48. Conclusion A combination of DWI with ADC mapping of the spine should proceed as soon as possible to ensure appropriate management. Early treatment with edaravone, aspirin, and steroid pulse therapy may prove beneficial for ASAS.

To investigate the origins of the warm absorbers in active galactic nuclei (AGNs), we study the ionization-state structure of the radiation-driven fountain model in a low-mass AGN (Wada et al. 2016) and calculate the predicted X-ray spectra, utilizing the spectral synthesis code Cloudy (Ferland et al. 2017). The spectra show many absorption and emission line features originated in the outflowing ionized gas. The O VIII 0.654 keV lines are produced mainly in the polar region much closer to the SMBH than the optical narrow line regions. The absorption measure distribution of the ionization parameter ($\xi$) at a low inclination spreads over 4 orders of magnitude in $\xi$, indicating multi-phase ionization structure of the outflow, as actually observed in many type-1 AGNs. We compare our simulated spectra with the high energy-resolution spectrum of the narrow line Seyfert 1 galaxy, NGC 4051. The model reproduces slowly outflowing (a few hundreds km s$^{-1}$) warm absorbers. However, the faster components with a few thousands km s$^{-1}$ observed in NGC 4051 are not reproduced. The simulation also underproduces the intensity and width of the O VIII 0.654 keV line. These results suggest that the ionized gas launched from sub-parsec or smaller regions inside the torus, which are not included in the current fountain model, must be important ingredients of the warm absorbers with a few thousands km s$^{-1}$. The model also consistently explains the Chandra/HETG spectrum of the Seyfert 2 galaxy, the Circinus galaxy., Comment: 13 pages, 13 figures, accepted for publication in ApJ

We present the result of a broadband (0.5-70 keV) X-ray spectral analysis of the late-merger galaxy Mrk 739, which contains a dual active galactic nucleus (AGN), Mrk 739E and Mrk 739W, with a separation of $\sim$3.4 kpc. The spectra obtained with NuSTAR, Chandra, XMM-Newton and Swift/BAT are simultaneously analyzed by separating the contributions from the two AGNs and extended emission with the Chandra data. To evaluate the reflection components from the AGN tori, we consider two models, a phenomenological one (pexrav and zgauss) and a more physically motivated one (XCLUMPY; Tanimoto et al. 2019). On the basis of the results with XCLUMPY, we find that the AGNs in Mrk 739E and Mrk 739W have intrinsic 2-10 keV luminosities of $1.0 \times 10^{43}$ and $7.5 \times 10^{41}\ \rm{erg}\ \rm{s}^{-1}$ absorbed by hydrogen column densities of $N_{\rm{H}} < 6.5 \times 10^{19}\ \rm{cm}^{-2}$ and $N_{\rm{H}} = 6.9^{+3.2}_{-1.7} \times 10^{21}\ \rm{cm}^{-2}$, respectively. The torus covering fraction of the material with $N_{\rm{H}} > 10^{22} \rm{cm}^{-2}$ in Mrk 739E, $C_{\rm{T}}^{(22)} < 0.50$ at a 90% confidence limit, is found to be smaller than those found for late-merger ultra/luminous infrared galaxies, $C_{\rm{T}}^{(22)} = 0.71\pm0.16$ (mean and standard deviation; Yamada et al. 2021). Considering the small star formation rate of Mrk 739E, we suggest that the gas-to-mass ratio of the host galaxy is an important parameter to determine the circumnuclear environment of an AGN in late merger., 14 pages, 4 figures, 3 tables, accepted for publication in ApJ

An 84-year-old woman developed blepharoptosis, diplopia, weakness of extremities, and dysphagia with elevation of serum CK levels after treatment with nivolumab against renal cell carcinoma. 3 Hz repetitive stimulation showed waning in the trapezius muscle, leading to the diagnosis of myasthenia gravis. Laboratory examination showed that anti-acetylcholine receptor antibody was negative. We performed IVIg and steroid therapy. However, her symptoms did not improve, and she died of respiratory failure, although serum CK levels ameliorated to the normal range. The results of autopsy showed atrophy of muscle fibers and massive infiltration of inflammatory cells in the endomysium of the iliopsoas muscle and diaphragm, indicating occurrence of myositis. Immunohistochemical analysis showed that CD8-positive T cells mainly infiltrates in the endomysium with a small number of CD4-potive T cells. Here, we report an autopsy case of nivolumab-induced myasthenia gravis and myositis.

We present the results of a systematic, broadband X-ray spectral analysis of nearby active galactic nuclei (AGNs) with the X-ray clumpy torus model (XCLUMPY; Tanimoto et al. 2019). By adding 16 AGNs newly analyzed in this paper, we study total 28 AGNs including unabsorbed and absorbed AGNs taken from Ichikawa et al. (2015) and Garc\'ia-Bernete et al. (2019). This is the largest sample whose X-ray and infrared spectra are analyzed by the clumpy torus models XCLUMPY and CLUMPY (Nenkova et al. 2008), respectively. The relation between the Eddington ratio and the torus covering factor determined from the X-ray torus parameters of each object follows the trend found by Ricci et al. (2017) based on a statistical analysis. We confirm the results by Tanimoto et al. (2020) that (1) the torus angular widths determined by the infrared data are larger than those by the X-ray data and that (2) the ratios of the hydrogen column density to V-band extinction ($N_{\rm H}/A_{\rm V}$) along the line of sight in obscured AGNs are similar to the Galactic value on average. Unobscured AGNs show apparently smaller line-of-sight $N_{\rm H}/A_{\rm V}$ ratios than the Galactic one. Our findings can be well explained by an updated unified picture of AGN structure including a dusty torus, dusty polar outflows, and dust-free gas, where the inclination determines the X-ray and optical classifications and observed torus properties in the X-ray and infrared bands., Comment: 24 pages, 6 figures, and 5 tables, accepted for publication in ApJ

The location of the obscuring “torus” in an active galactic nucleus (AGN) is still an unresolved issue. The line widths of X-ray fluorescence lines originating from the torus, particularly Fe Kα, carry key information on the radii of line-emitting regions. Utilizing XCLUMPY, an X-ray clumpy torus model, we develop a realistic model of emission line profiles from an AGN torus where we take into account line broadening due to the Keplerian motion around the black hole. Then, we apply the updated model to the best available broadband spectra (3–100 keV) of the Circinus galaxy observed with Suzaku, XMM-Newton, Nuclear Spectroscopic Telescope Array, and Chandra, including 0.62 Ms Chandra/HETG data. We confirm that the torus is Compton-thick (hydrogen column density along the equatorial plane is ), geometrically thin (torus angular width ), viewed edge-on (inclination ), and has supersolar abundance ( times solar). Simultaneously analyzing the Chandra/HETG first-, second-, and third-order spectra with consideration of the spatial extent of the Fe Kα line-emitting region, we constrain the inner radius of the torus to be times the gravitational radius, or for a black hole mass of (1.7 ± 0.3) × 106 M ⊙. This is about three times smaller than that estimated from the dust sublimation radius, suggesting that the inner side of the dusty region of the torus is composed of dust-free gas.

We apply a new X-ray clumpy torus model called XCLUMPY (Tanimoto et al. 2019), where the clump distribution is assumed to be the same as in the infrared clumpy torus model (CLUMPY) by Nenkova et al. 2008, to the broadband X-ray spectra of type-1 active galactic nuclei (AGNs) for the first time. We analyze the archival data of IC 4329A and NGC 7469 observed with NuSTAR/Suzaku and NuSTAR/XMM-Newton, respectively, whose infrared spectra were studied with CLUMPY by Ichikawa et al. 2015 and optical extinctions ($A_{\rm V}$) of the tori were estimated. We consider two models, invoking (Model 1) a relativistic reflection component from the accretion disk and (Model 2) a partial absorber. Assuming that the narrow Fe K$\alpha$ emission line at 6.4 keV originates from the torus, we separate the contribution of the torus reflection components in the total spectra. Our models yield equatorial hydrogen column densities of the tori to be $N^{\rm Equ}_{\rm H} =$ (0.53--1.43) $\times 10^{23}~\rm cm^{-2}$ and $N^{\rm Equ}_{\rm H} =$ (0.84--1.43) $\times 10^{24}~\rm cm^{-2}$, for IC 4329A and NGC 7469, respectively. We find that the $N_{\rm H}/A_{\rm V}$ ratios in the tori are by factors of 25--68 (IC 4329A) and 2.4--3.9 (NGC 7469) smaller than that in the Galactic interstellar medium (ISM). These results suggest that a non-negligible fraction of AGNs are 'dust-rich' compared with the Galactic ISM, as opposite to the general trend previously reported in many obscured AGNs., Comment: 13 pages, 11 figures, (accepted in the Astrophysical Journal, ApJ)

We apply XCLUMPY, an X-ray spectral model from a clumpy torus in an active galactic nucleus (AGN), to the broadband X-ray spectra of 10 obscured AGNs observed with both Suzaku and NuSTAR. The infrared spectra of these AGNs were analyzed with the CLUMPY code. Since XCLUMPY adopts the same clump distribution as that in the CLUMPY, we can directly compare the torus parameters obtained from the X-ray spectra and those from the infrared ones. The torus angular widths determined from the infrared spectra ($\sigma_{\mathrm{IR}}$) are systematically larger than those from the X-ray data ($\sigma_{\mathrm{X}}$); the difference ($\sigma_{\mathrm{IR}}-\sigma_{\mathrm{X}}$) correlates with the inclination angle determined from the X-ray spectrum. These results can be explained by the contribution from dusty polar outflows to the observed infrared flux, which becomes more significant at higher inclinations (more edge-on views). The ratio of the hydrogen column density and V-band extinction in the line of sight absorber shows large scatter ($\simeq$1 dex) around the Galactic value, suggesting that a significant fraction of AGNs have dust-rich circumnuclear environments., Comment: 17 pages, 3 figures, accepted for publication in ApJ

The effects of SM-197378, 2-[[[amino(imino)methyl]amino]carbonyl]-1-methyl-4-trifluoromethyl-1H-indol-7-yl=hydrogen=sulfate monohydrate, a novel potent Na+/H+exchange inhibitor, on heart injury were studied using a rabbit model involving 30 min of myocardial ischemia and 5 h of reperfusion. Intravenous administration of SM-197378 before ischemia reduced the infarct size by approximately 30-50% in a dose-dependent manner. This anti-necrotic effect was achieved without significant hemodynamic changes. Moreover, administration of SM-197378 before reperfusion also resulted in a significant, approximately 30-40%, reduction in the infarct size. The anti-necrotic effect of pre-ischemic bolus treatment with SM-197378 was compared with that of nicorandil, a K+channel opener with nitrate-like activity, and ischemic preconditioning. With 30 and 60 min of ischemia, the anti-necrotic effects of SM-197378 and ischemic preconditioning were similar and superior to that of nicorandil. With 90 min of ischemia, the anti-necrotic effect of SM-197378 was superior to that of ischemic preconditioning.

Mutations of Fas (CD95/Apo-1) gene have been reported in various malignancies and therefore the Fas gene has been considered to be a tumor suppressor gene. To examine an involvement of Fas gene as a tumor suppressor gene in radiation lymphomagenesis, we examined the loss of heterozygosity (LOH) in lymphomas from (MSM/Ms x MRL-MpJ/Fas (lpr)) F(1) and (BALB/cHeA x MRL-MpJ/Fas (lpr)) F(1) hybrid mice. Lymphoma development by X-irradiation was efficiently observed in both F(1) hybrids. Frequent LOH was found on chromosomes 12 and 4 in the tumors from both F(1) mice, but no allelic loss on chromosome 19 containing Fas locus was found, and no wild-type allele of the Fas gene was lost in 51 lymphomas. Therefore, the putative tumor-suppressor gene regions responsible for lymphomagenesis might not considerably differ due to the Fas gene status.

本文では気泡を混入した軽量土のせん断特性を解明することを目的とし, 気泡混入率が軽量土のせん断特性に及ぼす影響について検討している.その結果, 気泡混入率がせん断挙動に影響を及ぼすのは軸ひずみが5%以上であり, 体積ひずみは気泡混入率の高いほど大きくなり, 軽量土の破壊基準はqとp′の関係のみでなく体積ひずみを考慮した関係でも示され, この破壊基準も気泡混入率によって変化することが判明した.

This paper presents the changes of physical properties of inside slope of the decomposed granite soil, MASA, on the basis of the results of four tests, namely specific surface, X-ray diffraction, pore content and pFmoisture content.According to the results of these tests, the authors have recognised that the soil at the upper layer of natural slope composed of the Masa are influenced very much of the granulation and the alteration of constituent minerals and that soil texture of the upper layer changes from sandy soil to clayey soil.Moreover, we can think that the generation and development of the fine pores in soil particles are deeply concerned in the changes of soil texture from coarse to fine soil.With the change of soil texture, the soil of upper layer of MASA slope has been higher water retention comparing with lower one. It can be considered that there are deeply the effect of the total content and distribution of fine pores for high water retention of upper layer soil.

本研究ではセメント改良に気泡を混入した軽量土の力学的特性を解明することを目的として, 土を軽量化してゆく過程, すなわち粘性土・セメント改良土・軽量土のせん断挙動の変化について検討している. その結果, セメント改良土および軽量土では等方圧密時に特有の圧密降伏応力が存在し, その圧密降伏応力と拘束圧力の大小関係によって応力～ひずみ関係, 体積ひずみ, 間隙水圧が異なることから, 破壊線は過圧密・正規圧密飽和粘性土のように区別できることがわかった.

本研究では, 粒状体の一次性質が間隙比およびせん断特性に及ぼす影響を解明するために, 粒度組成 (粒径, 粒度分布), 粒子形状の一因子が独立して異なる試料を用いて最大密度・最小密度試験および圧密排水三軸試験を実施した. その結果, 間隙比およびせん断強さ, ダイレイタンシー特性には粒子形状の違いが大きく影響し, 粒径および粒度分布の影響は小さいことが明らかになった. また, せん断初期の剛性を示す変形係数は一次性質のいずれの因子にも無関係に余裕間隙比によって一義的に定まることがわかった.

寒冷地や山岳地域では凍結―融解作用が地盤に凍上現象やせん断強さの低下を発生させ凍害をもたらしている. 本研究は不飽和粘性土にクローズドシステムの状態で凍結―融解作用を与え, サクション力や温度勾配が凍結―融解時の体積変化に影響を与え, また凍結―融解時の体積変化によって融解後の土のせん断強さが異なることを明白にしている. さらにせん断強さの低下は有効応力の減少が原因であることを拘束圧力とサクション力によって定量的に表している.

砂粒子の形状が, せん断強さなどの工学的性質に影響を与えることは周知の事実である. しかし, 砂は個々の粒子が小さく, しかも形状の定量化の作業がかなり煩雑であるために工学的性質に与える粒子形状の影響に関する系統的な研究を阻害してきた. 本論文では粒状体の粒子形状を評価する凹凸係数FUを提案し, 種々の砂およびこれまで形状の評価に用いられてきた視覚印象図の定量化例について述べている.

The photoluminescence intensity of ZnS-AgInS(2) solid solution nanoparticles was remarkably enhanced by increasing the heating temperature to 180 degrees C, above which the emission was simply diminished, while ZnS coating of the particles resulted in further enhancement of PL intensity, giving the highest quantum yield of ca. 80%.

This study aims to appear isotropic compression characteristic, shearing characteristics and changes of suction in unsaturated cohesive soils by freezing and thawing under undrained conditions. The pore water pressure increases by freezing and thawing and the suction in soils decreases. In isotropic compression, changes of suction in subjected to freezing and thawing soils is greatly. The decrease in the suction is related to the pore formation of soil structure and the decrease in sheare strength.

The effects of 3-[2-({[amino(imino)methyl]amino}carbonyl)-4-chloro-1H-indol-1-yl]-1-propanesulphonic acid monohydrate (SM-198110), a novel potent Na+/H+ exchange inhibitor, and cariporide (Hoe642), another Na+/H+ exchange inhibitor, were studied in a myocardial ischaemia and reperfusion injury model. Anaesthetized rabbits were subjected to occlusion of the coronary artery for 30 min followed by reperfusion for 5 h. SM-198110 or cariporide was administered before ischaemia and before reperfusion. We also assessed the anti-necrotic effect of SM-198110 when given before reperfusion, both alone and together with glibenclamide, a K(ATP) channel blocker, 5-hydroxydecanoate (5-HD), a mitochondrial K(ATP) channel-selective blocker and 8-(p-sulphophenyl)-theophylline (8-SPT), an adenosine receptor blocker. The infarct size was reduced dose-dependently by i.v. administration of SM-198110 before ischaemia, with a significant reduction in serum creatine phosphokinase activity. Infarct sizes, normalized to the size of the area-at-risk (means+/-SE) were: vehicle 56.6+/-3.7%; low-dose SM-198110 39.2+/-6.3%; mid-dose 32.8+/-7.4% (P0.05); high-dose 22.1+/-6.7% (P0.01). This anti-necrotic effect of SM-198110 was achieved without significant haemodynamic changes. Cariporide given before ischaemia also reduced infarct size significantly and dose-dependently. SM-198110 administered before reperfusion also resulted in a dose-dependent reduction in the infarct size. Infarct sizes were: vehicle 56.6+/-3.7%; low-dose SM-198110 44.5+/-5.7%; mid-dose 36.3+/-6.6% (P0.01); high-dose 34.7+/-3.8% (P0.01). In contrast, cariporide given before reperfusion did not reduce infarct sizes significantly. The anti-necrotic effect of SM-198110 was observed even when given 10 min after the beginning of reperfusion. Glibenclamide and 5-HD abolished the anti-necrotic effect of treatment before reperfusion with SM-198110. However, the co-administration of 8-SPT with SM-198110 did not affect infarct size. These results suggest that, in addition to Na+/H+ exchange inhibition, mitochondrial and/or sarcolemmal K(ATP) channels contribute to the anti-necrotic effect of SM-198110 when the latter is given before reperfusion.

Non-stoichiometric AgInS2 (AIS) semiconductor particles were synthesized by the thermal decomposition of single-source precursors in solutions of two kinds of primary amines (oleylamine and octylamine). The Ag content in the resulting nanoparticles was controlled by adjusting the chemical composition of the precursor used, in which the mole ratio of Ag+ to total metal ions was varied from 0.1 to 0.7, resulting in the production of non-stoichiometric AIS particles with varying amounts of Ag vacancies. The average size of AIS particles was slightly decreased from 4.3 to 3.8 nm on changing the solvent from oleylamine to octylamine in the preparation, while the particle size seemed to be constant regardless of the content of Ag. On the other hand, the optical properties of AIS particles were considerably modified depending on the Ag content in the particles. The absorption onset was blue-shifted from 750 to 580 nm with a decrease in the Ag content, due to the enlargement of the energy gap of particles. Intense photoluminescence originating from the donor–acceptor pair recombination was observed for each kind of AIS particle and then the photoluminescence peak wavelength was also blue-shifted from 830 to 650 nm, being similar to the behavior of the absorption onset. The maximum photoluminescence quantum yield was ca. 70% for octylamine-modified AIS nanoparticles having a ratio of Ag+ to total metal ions of 0.37, which probably contained the optimum amount of Ag vacancies acting as the sites of donor–acceptor pair recombination with few surface defect sites for non-radiative recombination.

This paper presents a practical 3-dimensional measurement system which is applied to geometrical accuracy measurenient for large-scale steel bridge members. The measuring niethod is based on stereo vision using precision CCD-cameras linked with a personal computer. The developed system can automatically recognize every target point in its view field and determine theX Y and Z coordinates within a remarkable short time and the measurement accuracy of the system is better than 0. 5 mm for a view field of about 3 m(H) by 2. 3 m(v). This system is applied to an inspection station for the measurement of steel bridge members. The inspection station can measure the geometrical and dimensional accuracy of a steel bridge member of about 3 m x 4 m x 20 in in maximum size with an acceptable measurement accuracy and the results obtained from practical runs for the last three years verify the feasibility of the developed system.

In cold and snowy areas, road pavement is greately damaged by frost heave in the ground.This paper describes the measurement results of temperature, underground temperature, frost heaving, and soil profile obtained by field investigations (e. g. pit cutting and boring survey) at an elevation of 1750m in the Kita Yatsugatake Tateshina lava plateau.This study led to the conclusion that fairly accurate estimates of frost heave in the field can be obtained through the use of the Segregation Potential Theory by Konrad and Morgenstern. In addition, the soil profile at the site was recorded.

In order to investigate the influence of pore water pressure on landslide occurrence, we conducted model test in laboratory and two kinds of ring shear test on cohesive soil.In addition, we made slope stability analyses by using the results of ring shear test.Our main conclusions from the laboratory investigations are as follows; i) Landslide may be occurred by increment of pore water pressure at the slip surface. Therefore, when making slope stability analyses, pore water pressures should be measured directly all along the slip surface with piezoelectric meters. ii) The shearing strength parameters of soil for use in slope stability analyses was shown. The shearing strength parameters using a ring shear apparatus are useful in making stability analyses.

In the case of discussing on stability of slopes in landslide areas, investigations and researches from soil engineering point of view are indispensable. However, there are very few reports about those aspects.In this paper; as a basic study of understanding soil properties at landslide areas in Hokuriku region, the accumulated data obtained at various location in Noto peninsula are analyzed, and physical and mechanical properties and in correlation between soil constants and grain size characteristics of material relevant to landslide are described.Moreover, comparative studies on soil properties of Noto peninsula, south-western parts of Niigata Prefecture and Tokushima Prefecture are carried out.

In order to take a knowledge on the seasonal variations of groundwater level and pore water pressure in landslide areas, the field investigations were carried out during five years. Based on the field investigation, the following conclusions can be drawn: 1) Groundwater level and pore water pressures at the slip surface in landslide areas have changed seasonally, with marked increases after the snow-melting and heavy rainfall seasons. 2) Pore water pressures at the slip surfaces do not always coincide with hydraulic pressure values calculated from the groundwater level. Therefore, when making slope stability analyses and taking preventive measures against reactivatings, pore water pressures should be measured directly all along the slip surface with electric piezometers. 3) Landslide is liable to occur during two weeks after heavy rainfall because of time lag between groundwater level and rainfall, therefore, the careful attention should be necessary for these period. 4) The slope stability analysis should be conducted on the shearing strength considered the overconsolidated states of soils due to the increasing of pore water pressures.

In order to investigate the mechanism of frost heaving in cohesive soil stratum, laboratory test was performed on cohesive soil.The main concluding remarks derived from these studies are as follows; i) Having high water content and high saturation, specimens tend to display great amount of moisture migration and large frost heave, especially for small freezing rate. ii) Frost heaving process consists of primary and secondary processes. Furthermore, a simple calculation method of frost heave in laboratory test was proposed. iii) Although the soil sample was in the same state, a different pattern of frost heaving pressure was produced for a variation of void distribution in the specimen. This characteristic is closely connected with occurrence of ice lens.

In order to investigate the behaviour of the groundwater level, pore water pressure and underground temperature during snow-melting season in landslide areas, the field investigations were carried out.Our main conclusions from the field investigations are: i) The decrease of snow depth during snow-melting season has been occurred at uniform rate, irrespective of the snow depth. In addition, the snow-melting which is equivalent to the rainfall about 30mm in a day was observed. ii) The time of the seepage to the grounds of snow-melting due to thawing may be predicted by measuring the underground temperature.

In order to investigate a quantitative approach to the shear strength gained due to a consolidation process within a 24 hours period and to check the validity of a 3 t method for the closing of the consolidation period (JSSMFE, 1979), a set of undrained triaxial tests was performed on a cohesive soil. It was found that the process of increase in undrained shear strength consists of primary and secondary processes, and that the 3 t method for the closing of the consolidation period in laboratory tests (JSSMFE, 1979), is a useful method for determining undrained shear strength. The 21 method, however, may be used when the shortening of the consolidation period is required.