Discrimination of psychoactive fungi (commonly called "magic mushrooms") based on the DNA sequence of the internal transcribed spacer region

'Magic mushrooms' (MMs) are psychoactive fungi containing the hallucinogenic compounds, psilocin (1) and psilocybin (2). Since June 6, 2002, these fungi have been regulated by the Narcotics and Psychotropics Control Law in Japan. Because there are many kinds of MMs and they are sold even as dry powders in local markets, it is very difficult to identify the original species of the MMs by morphological observation. Therefore, we investigated the internal transcribed spacer (ITS) region in the ribosomal RNA gene of MMs obtained in Japanese markets to classify them by a genetic approach. Based on the size and nucleotide sequence of the ITS region amplified by PCR, tested MMs were classified into 6 groups. Furthermore, a comparison of the DNA sequences of the MMs with those of authentic samples or with those found in the databases (GenBank, EMBL and DDBJ) made it possible to identify the species of tested MMs. Analysis by LC revealed that psilocin (1) was contained at the highest level in Panaeolus cyanescens among the MMs, but was absent in the Amanita species.     

“Segment-wise model” for theoretical simulation of barely visible indentation damage in composite sandwich beams: Part II – Experimental verification and discussion

When localized transverse loading is applied to a sandwich structure, the facesheet locally deflects and the core crushes. A residual dent induced by the core crushing significantly degrades the mechanical properties of the sandwich structure. In a previous paper, the authors established a “segment-wise model” for theoretical simulation of barely visible indentation damage in honeycomb sandwich beams with composite facesheets. Honeycomb sandwich beam was divided into many segments based on the periodic shape of the honeycomb and complicated through-thickness characteristics of the core were integrated into each segment. In this paper, the new model is validated by experiments using specimens with different types of honeycomb cores. In addition, the damage growth mechanism under indentation load was clarified from the viewpoint of the reaction force from the core to the facesheet. The applicability of the model to other types of core materials is also discussed.     

Possible 3He Boltzmann Gas Formed on Three-Dimensional Nanopores Preplated with 4He

We have measured the heat capacity of ³He adsorbed on three-dimensionally connected nanopores, 2.7 nm in diameter, preplated with about 1.3 atomic layers of ⁴He. At low coverages of ³He, the ³He heat capacity is roughly constant at the measured temperatures between 0.1 and 1 K. Its molar heat capacity is on the order of the gas constant R, between 1.1R and 1.8R. This suggests a Boltzmann gas state of the adsorbed ³He. At high coverages, the heat capacity is likely approaching linear in T at low temperatures, which suggests a degenerate state at further lower temperatures.     

Present status and future prospects of spherical aberration corrected TEM/STEM for study of nanomaterials?

The present status of Cs-corrected TEM/STEM is described from the viewpoint of the observation of nanomaterials. Characteristic features in TEM and STEM are explained using the experimental data obtained by our group and other research groups. Cs correction up to the 3rd-order aberration of an objective lens has already been established and research interest is focused on correcting the 5th-order spherical aberration and the chromatic aberration in combination with the development of a monochromator below an electron gun for smaller point-to-point resolution in optics. Another fundamental area of interest is the limitation of TEM and STEM resolution from the viewpoint of the scattering of electrons in crystals. The minimum size of the exit-wave function below samples undergoing TEM imaging is determined from the calculation of scattering around related atomic columns in the crystals. STEM does not have this limitation because the resolution is, in principle, determined by the probe size. One of the future prospects of Cs-corrected TEM/STEM is the possibility of extending the space around the sample holder by correcting the chromatic and spherical aberrations. This wider space will contribute to the ease of performing in situ experiments and various combinations of TEM and other analysis methods. High-resolution, in situ dynamic and 3D observations/analysis are the most important keywords in the next decade of high-resolution electron microscopy.     

Synthesis and hydrophilic property of polypropylene-graft-poly(polyethylene glycol-methacrylate) (PP-g-P(PEGMA))

Polypropylene-graft-poly(polyethylene glycol-methacrylate) (PP-g-P(PEGMA)), which is a hydrophobic-hydrophilic graft copolymer, was synthesized by a combination of an atom transfer radical polymerization (ATRP) of PEGMA with brominated polypropylene (PP-Br), which was synthesized from PP-OH prepared by metallocene-catalyzed copolymerization. Its structure was confirmed by ¹H NMR and GPC analyses. Transmission electron microscope (TEM) micrographs of PP-g-P(PEGMA) revealed the nanometer level microphase-separation morphology between the PP segment and the P(PEGMA) segment. The obtained PP-g-P(PEGMA) showed water-absorbing property as well as thermostability.     

Japan and the United States: Cooperation vs. competition in high-technology

Japan and the United States share many similar objectives in high-technology. The cooperation between the two countries has spread widely. However, the high-technology area, which is a high growth and most promising sector, has been marked by intensive commercial competition sometimes leading to excessive anxiety and unnecessary confrontation.     

Health-monitoring technologies for alumina-fiber-reinforced plastics

Transmitted light could detect matrix cracks that occurred in the early stages of fracture of alumina-fiber-reinforced plastics (alumina-FRPs); these cracks could not be detected by acoustic emission (AE). An optical-fiber Bragg grating (FBG) sensor could detect the matrix cracks but it must be embedded in the FRPs. To determine which wavelength is sensitive to the defects in the FRP, the spectra of the transmitted and reflected light were measured. The intensity of the transmitted light, especially in the visible region (wavelength: 400–800 nm), decreased as the bending stiffness of the test piece decreased. It is thus concluded that to monitor the decrease in bending stiffness of FRPs, a simple sensor using a visible ray is good enough. And this transmitted-light NDE technique can work in the strong electromagentic field associated with a superconductor. It will therefore be useful for detecting defects in the FRP of the load-support system in service.     

One-Dimensional Phonon State of 4He Films Adsorbed in Straight Nanopores

We have studied heat capacities of ⁴He adsorbed in straight nanopores 1.8, 2.2, and 2.8 nm in diameter. Heat capacities of the ⁴He fluid film on the solid layer at 0.08–0.4 K show power laws close to T in 1.8 nm pores, close to T ² in 2.8 nm pores, and a crossover from T to T ² with increasing temperature in 2.2 nm pores. These heat capacities are explained by a model assuming a phonon dispersion with continuous one-dimensional (1D) states in the axial direction and discrete energy levels in the azimuthal direction. By fitting experimental data to the model, the phonon velocity along the pore axis and the energy gap for propagation in the cross section are derived. At temperatures sufficiently lower than the energy gap, where the thermal wave length of phonons is much longer than the effective pore diameter, the ⁴He fluid films show a T-linear heat capacity of 1D phonons propagating only along the pore axis. At higher temperatures, a 1D-2D crossover of phonons occurs.      

Thermal proof testing of ceramics

The possibility of thermal proof testing with thermal stress induced by quenching was examined. For this purpose, the bending strength and the critical temperature difference for quenching into water and quench oil for soda-lime-silica glass were measured before and after proof testing by quenching the specimens into water, ethyl alcohol, silicon oil and quench oil. Proof testing by water, ethyl alcohol and silicon oil quenching modified the distribution of the critical temperature difference as expected, but not that of the bending strength at all. It is suggested that proof testing by rapid quenching is a useful method for truncating the critical temperature difference distribution of ceramic components of heat engines and so on.     

The initial step of the thermal unfolding of 3-isopropylmalate dehydrogenase detected by the temperature-jump Laue method

A temperature-jump (T-jump) time-resolved X-ray crystallographictechnique using the Laue method was developed to detect small,localized structural changes of proteins in crystals exposedto a temperature increase induced by laser irradiation. In achimeric protein between thermophilic and mesophilic 3-isopropylmalatedehydrogenases (2T2M6T), the initial structural change uponT-jump to a denaturing temperature (~90°C) was found tobe localized at a region which includes a ß-turn and aloop located between the two domains of the enzyme. A mutant,2T2M6T-E110P/S111G/S113E, having amino acid replacements inthis ß-turn region with the corresponding residues ofthe thermophilic enzyme, showed greater stability than the originalchimera (increase of T_m by ~10°C) and no T-jump-inducedstructural change in this region was detected by our method.These results indicate that thermal unfolding of the originalchimeric enzyme, 2T2M6T, is triggered in this ß-turn region.