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In this study, the precipitation of minerals onto rock surfaces was investigated to consider whether sealing of pores and cracks in rock can be accelerated. Cylindrical specimens were prepared and then kept in purified water with powders of high-strength and ultra-low-permeability concrete (HSULPC), which will be used to confine transuranic wastes in Japan. Then, the rock specimens were weighed and the surfaces of rock specimens were inspected under a microscope. It was recognized that precipitation occurred on the surface of the rock specimens. It was also shown that precipitation did not occur on rock specimens kept in water without HSULPC. The weight of all specimens stored in HSULPC increased, and the observed weight change was larger for rocks with higher porosities. It is concluded that precipitation of minerals occurs on the rock surface when the rock is kept in water with HSULPC powders. From the results obtained in this study, it is suggested that the sealing of pores and cracks in rock can be accelerated by the precipitation of calcium compounds using HSULPC. It is concluded that HSULPC is useful for underground radioactive waste disposal. [ABSTRACT FROM AUTHOR]

Clay-rich fault gouge in the principal slip zones of faults stores abundant water within pores and between clay interlayers. During the preparation of thin-sections and rock chips for microstructural observations, fault-gouge samples are commonly air-dried at room temperature or in an oven. However, during the drying process, remnant liquid water between gouge grains produces an inter-particle adhesion force (liquid-bridge force), which rearranges the grain-to-grain structure, likely resulting in a disturbance of the original fabric. For this study, we prepared gouge samples from the Itozawa fault, northeastern Japan, using a t -butyl alcohol freeze-drying method that mitigates drying-induced fabric disturbance. We then compared the microstructure of our samples with those prepared using the conventional air-drying method. The freeze-dried samples preserve a smooth fault plane, clearly defined nanoparticles, and well-developed shear-sense indicators, including slickenlines and Riedel shear planes. In contrast, the air-dried samples underwent shrinkage during drying, which distorted the geometry of the fault plane. These air-dried samples lack nanoparticles and display only a weak shear fabric. We conclude that microstructural observations on samples prepared using the t -butyl alcohol freeze-drying method, compared with conventional air-drying, could preserve more evidence for the retrieval of fault information, including the kinematics, slip stability, and dynamic weakening mechanism of a fault. • We compare microstructures of air- and freeze-dried gouge of the Itozawa fault, Japan. • Air-drying distorts fault planes and destroys microstructural shear indicators. • Freeze-dried samples preserve clear shear indicators. • Shear indicators include slickenlines and Riedel shear planes. • Sample preparation methods can greatly affect microstructural faulting signatures. [ABSTRACT FROM AUTHOR]

The Yuigahama Chusei Shudan Bochi site ( ad twelveth to thirteenth centuries), located along the seashore of the southern end of Kamakura City in Japan, and has yielded a mass grave containing hundreds of human crania. The purpose of this study is to document cut marks on crania made by an edged weapon, paying specific attention to individuals who may exhibit scratch marks, and to understand the variability of weapon-related traumas in the medieval period in Japan. The observation leads to tentative findings regarding the identification and interpretation of weapon-related traumas of human skeletal remains. From macroscopic observation, the marks display the sharpness of cut surfaces which are characteristic of unhealed cut marks. Scanning electron microscopic observation of the marks also shows that they are V-shaped in cross-section, a morphological feature that is characteristic of cut marks. This study first demonstrates that the scratches on the crania have morphological features consistent with human-induced cut marks, and that the macroscopic and microscopic approaches provide important information for identifying anthropogenic cut marks on the human skeletal remains from an archaeological site in Japan. [ABSTRACT FROM AUTHOR]

Abstract: The sources and character of individual metal and metalloid particles from atmospheric dry depositions in Kobe, Japan were investigated. Japan faces long-range pollutant transportation from northeastern Asia during winter and spring. Information regarding their properties and sources is useful for evaluating their affects on the environment and human health. Individual metal and metalloid particles that were collected for every 24h on the plate, which was designed to reduce a local turbulence, were characterized for their composition, diameter, and deposition fluxes using a field emission scanning electron microscope with an energy dispersive X-ray spectrometer. Approximately 3000 metal and metalloid particles were classified into 14 types based on their composition and further classified into four groups based on their distribution patterns. They are (A) Fe–O, Fe–Ba–Sb–Cu–S–Ti–O, Fe–Zn–O, Zn–O, Ni–O, and Mn–Fe–O; (B) Cu–Zn–O and Cu–Sn–O; (C) Pb–O, Sn–Sb–O, and Ag–O; (D) Pb–Zn–Cl–Si–S–O and Bi–Cl–O. From these data, this study suggests their sources as the Asian continent (Group A), local source (Group B), multiple sources (Group C), and incineration process (Group D). This study shows (1) the sources and character of individual metal and metalloid particles from short-term atmospheric depositions in Kobe, Japan and (2) application of individual particle analysis for atmospheric depositions. [Copyright &y& Elsevier]

Morphological and toxicological analyses were performed on hallucinogenic mushrooms that are currently circulated in Japan. Scanning electron microscope (SEM) indicated a three-dimensional microstructures in the mushrooms. The complementary use of SEM with an optical microscope was effective for observing characteristic tissues, such as basidiomycetes, spores, cystidia and basidia. Hallucinogenic alkaloids were extracted with methanol and determined by high performance liquid chromatography (HPLC) with a UV detector set at 220 nm. The psilocin/psilocybin contents in Psilocybe cubensis were in the range of 0.14–0.42%/0.37–1.30% in the whole mushroom (0.17–0.78%/0.44–1.35% in the cap and 0.09–0.30%/0.05–1.27% in the stem), respectively. The hallucinogenic alkaloids in Copelandia were 0.43–0.76%/0.08–0.22% in the whole mushroom (0.64–0.74%/0.02–0.22% in the cap and 0.31–0.78%/0.01–0.39% in the stem). It thus appears that P. cubensis is psilocybin-rich, whereas Copelandia is psilocin-rich. [Copyright &y& Elsevier]

Gibberellins (GAs) are the plant hormones that control many aspects of plant growth and development, including stem elongation. Genes encoding enzymes related to the GA biosynthetic and metabolic pathway have been isolated and characterized in many plant species. Gibberellin 2-oxidase (GA2ox) catalyzes bioactive GAs or their immediate precursors to inactive forms; therefore, playing a direct role in determining the levels of bioactive GAs. In the present study, we produced transgenic plants of the liliaceous monocotyledon Tricyrtis sp. overexpressing the GA2ox gene from the linderniaceous dicotyledon Torenia fournieri (TfGA2ox2). All six transgenic plants exhibited dwarf phenotypes, and they could be classified into two classes according to the degree of dwarfism: three plants were moderately dwarf and three were severely dwarf. All of the transgenic plants had small or no flowers, and smaller, rounder and darker green leaves. Quantitative real-time reverse transcription-polymerase chain reaction (PCR) analysis showed that the TfGA2ox2 expression level generally correlated with the degree of dwarfism. The endogenous levels of bioactive GAs, GA1 and GA4, largely decreased in transgenic plants as shown by liquid chromatography-mass spectrometry (LC-MS) analysis, and the level also correlated with the degree of dwarfism. Exogenous treatment of transgenic plants with gibberellic acid (GA3) resulted in an increased shoot length, indicating that the GA signaling pathway might normally function in transgenic plants. Thus, morphological changes in transgenic plants may result from a decrease in the endogenous levels of bioactive GAs. Finally, a possibility of molecular breeding for plant form alteration in liliaceous ornamental plants by genetically engineering the GA metabolic pathway is discussed., (Copyright © 2013 Elsevier GmbH. All rights reserved.)