Rainfall-induced failures of volcanic slopes subjected to freezing and thawing

AbstractRainfall- and earthquake-induced failures of slopes formed by volcanic soils occur frequently in Hokkaido, Japan. The aim of this study is to clarify the failure mechanisms of volcanic slopes caused by both rainfall and freeze–thaw action in cold regions such as Hokkaido. Using model slopes of different shapes formed by volcanic soils, a series of rainfall tests are conducted under field conditions in which a spray nozzle is used to simulate rainfall intensity. Test results show that the surface failure of volcanic slopes differs depending strongly on the angle and the initial moisture content of the slopes. Based on the results of the model testing, the effects of freezing and thawing on the failure mechanism are drawn upon to propose an evaluation method for slope stability. In consideration of the model test results, it is found that the formation of a frozen layer and the softening of the slope surface, due to the freeze–thaw action, are significant for the stability of volcanic slopes in cold regions, and that slope failure can be uniquely assessed by the changes in water content in zones subjected to rainfall and freeze–thaw action

Lateral Flow Deformation Evaluation of Ground-Structure System under Various Cyclic Loading Conditions

In order to clarify the mechanical behaviors of sand grounds induced by various loadings including sea wave forces, traffic vibrations and earthquake etc., a series of model tests were carried out on model structure-ground system by using, the two-dimensional plane strain soil box apparatus. It was found that; (1) the lateral flow behavior of ground depends strongly on settlement performance of a structure, (2) the bearing capacity of ground may be evaluated by a failure envelope which is depicted in M-V-H plane irrespective of the difference in loading conditions and (3) the stability of sand ground-structure system can be assessed on the basis of a parameter Vσ/ Vρ which quantifies the lateral flow deformation

Bayesian Modeling for Estimating Cattle’s Dung position in Pasture

Livestock excrement is one of the major sources of greenhouse gas (GHG) emission in pasture. As a first step in evaluating its contribution to overall GHG emissions, an understanding of excretion distribution patterns in pastures is required. Betteridge et al. (2010) describe a urine sensor that detects and logs each urination event of female sheep and cattle. The urine sensor records time and ambient temperature at one-second intervals however, patters of dung distribution are not specified. The objective of this study was to predict spatial distribution of cattle dung. The knowledge of livestock excrement position may be useful for farmers to minimize overall GHG emissions

Initial results from the InSight mission on Mars

NASA’s InSight (Interior exploration using Seismic Investigations, Geodesy and Heat Transport) mission landed in Elysium Planitia on Mars on 26 November 2018. It aims to determine the interior structure, composition and thermal state of Mars, as well as constrain present-day seismicity and impact cratering rates. Such information is key to understanding the differentiation and subsequent thermal evolution of Mars, and thus the forces that shape the planet’s surface geology and volatile processes. Here we report an overview of the first ten months of geophysical observations by InSight. As of 30 September 2019, 174 seismic events have been recorded by the lander’s seismometer, including over 20 events of moment magnitude Mw = 3–4. The detections thus far are consistent with tectonic origins, with no impact-induced seismicity yet observed, and indi- cate a seismically active planet. An assessment of these detections suggests that the frequency of global seismic events below approximately Mw = 3 is similar to that of terrestrial intraplate seismic activity, but there are fewer larger quakes; no quakes exceeding Mw = 4 have been observed. The lander’s other instruments—two cameras, atmospheric pressure, temperature and wind sensors, a magnetometer and a radiometer—have yielded much more than the intended supporting data for seismometer noise characterization: magnetic field measurements indicate a local magnetic field that is ten-times stronger than orbital estimates and meteorological measurements reveal a more dynamic atmosphere than expected, hosting baroclinic and gravity waves and convective vortices. With the mission due to last for an entire Martian year or longer, these results will be built on by further measurements by the InSight lander

Studies on the Luminous Fungus, Pleurotus japonicus sp. nov.

The chief result of my observations on Pleurotus japonicus may be summarized as follows: 1. The fungus belongs to the genus Pleurotus, being characterized by the position of stem at one side of pileus, by the decurrent gills, by the spores presenting white color when caught in a mass, & c. It somewhat resembles Pleurotus rapidus Kalchbr. and Pleurotus ostreatus Jacq., but apparently represents a new and distinct species. 2. The fungus usually grows in clusters, overlapping one another, on the decaying trunk of the beech (Fagus sylvatica L. var. Sieboldi Maxim.), which is the only host as yet known. It is found in the Autumn. 3. The light is emitted by the gills only; all other parts of the fungus, including spores, are not luminous. The gills are uniformly luminous all over. Both hymenium and trama of gills are luminous. The juice squeezed out from the luminous gills are non-luminous. 4. The minimum and maximum temperatures in which the present fungus emits light are 3-5℃. and 40℃. respectively. The optimum temperature may be put down at 10-15℃. 5. In nitrogen gas, the luminosity begins to fade after ten seconds, becomes very feeble after fifty seconds, is scarcely recognizable after one minute and twenty seconds, and finally becomes completely invisible after one minute and forty seconds. In hydrogen gas, it begins to fade after ten seconds and becomes invisible in thirty minutes. In ether vapor, the light becomes invisible after one minute and fifty seconds, and if immediately after that, the object be taken out into the air, the luminosity returns after thirty seconds. In chloroform vapor, it vanishes in fifty-five seconds. Exposure to oxygen gas causes no change in the luminosity. Gills with faded luminosity become temporarily highly luminous some minutes after being in gaseous either or chloroform. 6. The fungus with luminous area of about 100 sq. cm. gives sufficient light for seeing Roman alphabets of about 8 mm. diameter in the dark. The luminosity can be fully perceived at a distance of thirty metres or more. 7. The light is white in color, not greenish, bluish or yellowish as in almost all other cases of luminous fungi. Photographic images of the luminous surface of the fungus taken in the dark room, by exposure of seven and half hours and also of twenty-four hours, were all very faint. Good dark prints on white background were secured of the leaves placed between the luminous fungus surface and a photographic dry-plate, by an exposure of one hour and fifty minutes

Stability Evaluation of Volcanic Slope Subjected to Rainfall and Freeze-Thaw Action Based on Field Monitoring

Rainfall-induced failures of natural and artificial slopes such as cut slopes, which are subjected to freezing and thawing, have been frequently reported in Hokkaido, Japan. In particular, many failures occur intensively from spring to summer seasons. Despite numerous field studies, explanation of their mechanical behavior based on in situ data has not yet been completely achieved due to the difficulty in grasping failure conditions. This study aims at clarifying the aspects of in-situ volcanic slopes subjected to rainfall and freeze-thaw action. The changes in soil moisture, pore pressure, deformations, and temperatures in the slope were investigated using soil moisture meters, tensiometers, thermocouple sensors, clinometers, settlement gauges, an anemovane, a snow gauge, and a rainfall gauge. The data generated from these measures indicated deformation in the slope examined mainly proceeded during the drainage process according to changes in soil moisture. Based on this data, a prediction method for failures is discussed in detail

Clinical Features of Neurodevelopmental Outcomes in Children with Preterm Severe Fetal Growth Restriction: A Retrospective Observational Study

Introduction: Fetal growth restriction (FGR) is a clinical condition wherein a fetus fails to achieve the expected growth potential. Although FGR is the leading cause of perinatal morbidity and mortality, there is a lack of knowledge about the long-term developmental outcomes of children who had FGR in Japan. Here, we sought to clarify the features of neurodevelopmental outcomes in preterm-born children with severe FGR (sFGR) and identify associated clinical factors. Methods: The clinical data of 26 preterm sFGR cases and 26 preterm appropriate for gestational age (AGA) cases with a similar gestational age distribution were reviewed retrospectively. Developmental quotient (DQ) scores assessed during the 1- and 2-year corrected ages using the Kyoto Scale of Psychological Development were analyzed. Results: sFGR was diagnosed at 26 (18-34) weeks of gestation, and the gestational age at delivery was 31 (25-36) weeks. The overall DQ scores of children in the sFGR group were significantly lower than those in the AGA group (80 vs. 90.5, P = 0.0127). Of the three areas that comprise the DQ (Postural-Motor, Cognitive-Adaptive, and Language-Social), the sFGR group only showed significantly lower DQ scores (72.5 vs. 88, P = 0.0255) in the Language-Social area. Both fetal body weight and fetal body weight Z score at birth significantly correlated with the DQ scores (r = 0.4912, P = 0.0108, and r = 0.5621, P = 0.0028), whereas neither the duration of fetal growth arrest nor the gestational age at birth correlated with the DQ scores (r = 0.3598, P = 0.0842, and r = 0.3522, P = 0.0776). Conclusions: Our results indicate that preterm-born children with sFGR have greater neurodevelopmental impairment than preterm-born children without FGR, specifically in terms of the DQ scores for the Language-Social area. It is imperative to encourage continuous long-term follow-up and appropriate interventions after birth