Metabolomics Analyses Reveal Metabolites Affected by Plant Growth-Promoting Endophytic Bacteria in Roots of the Halophyte Mesembryanthemum crystallinum

Mesembryanthemum crystallinum L. (common ice plant) is an edible halophyte. However, if ice plants are used to phytoremediate salinity soil, there are problems of slow initial growth, and a long period before active NaCl uptake occurs under higher salinity conditions. Application of endophytic bacteria may improve the problem, but there remain gaps in our understanding of how endophytic bacteria affect the growth and the biochemical and physiological characteristics of ice plants. The aims of this study were to identify growth-promoting endophytic bacteria from the roots of ice plants and to document the metabolomic response of ice plants after application of selected endophytic bacteria. Two plant growth-promoting endophytic bacteria were selected on the basis of their ability to promote ice plant growth. The two strains putatively identified as Microbacterium spp. and Streptomyces spp. significantly promoted ice plant growth, at 2-times and 2.5-times, respectively, compared with the control and also affected the metabolome of ice plants. The strain of Microbacterium spp. resulted in increased contents of metabolites related to the tricarboxylic acid cycle and photosynthesis. The effects of salt stress were alleviated in ice plants inoculated with the endobacterial strains, compared with uninoculated plants. A deeper understanding of the complex interplay among plant metabolites will be useful for developing microbe-assisted soil phytoremediation strategies, using Mesembryanthemum species.     

Short‐term prediction of water flow data into hydroelectric power stations using local fuzzy reconstruction method

For predicting the flow into a hydroelectric power station, complex natural phenomena have to be dealt with, so conventional mathematical models based on hydraulics may not produce satisfactory results. When a neural network is used, its construction cannot be easily determined, and extra neural networks must be provided separately in addition to the normal neural network, according to experts' opinions about the problem. To solve these problems, the authors took the standpoint that if the inflow rate time‐series data for hydroelectric power stations exhibit deterministic chaos, the status in the near future can be predicted. Thus, the authors have applied the local fuzzy reconstruction method as a deterministic nonlinear short‐term prediction method to data for the flow of water into hydroelectric power stations. In this paper, typical outflow analysis method using conventional mathematical models is first described briefly. Next, the “Local Fuzzy Reconstruction Method” is described. Third, chaotic behavior of water flow data into hydroelectric power stations is illustrated. Finally, the results of applying the method to the prediction of the flow into hydroelectric power stations are presented. © 2000 Scripta Technica, Electr Eng Jpn, 130(4): 99–106, 2000     

Chymase as a Novel Therapeutic Target in Acute Pancreatitis

Acute pancreatitis is still a life-threatening disease without an evidenced therapeutic agent. In this study, the effect of chymase in acute pancreatitis and the possible effect of a chymase inhibitor in acute pancreatitis were investigated. Hamsters were subcutaneously administered 3.0 g/kg of L-arginine to induce acute pancreatitis. Biological markers were measured 1, 2, and 8 h after L-arginine administration. To investigate the effect of a chymase inhibitor, a placebo (saline) or a chymase inhibitor TY-51469 (30 mg/kg) was given 1 h after L-arginine administration. The survival rates were evaluated for 24 h after L-arginine administration. Significant increases in serum lipase levels and pancreatic neutrophil numbers were observed at 1 and 2 h after L-arginine administration, respectively. Significant increases in pancreatic neutrophil numbers were observed in the placebo-treated group, but they were significantly reduced in the TY-51469-treated group. A significant increase in the pancreatic tumor necrosis factor-α mRNA level was observed in the placebo-treated group, but it disappeared in the TY-51469-treated group. Chymase activity significantly increased in the placebo-treated group, but it was significantly reduced by treatment with TY-51469. The survival rate significantly improved in the TY-51469-treated group. A chymase inhibitor may become a novel therapeutic agent for acute pancreatitis.     

Magnetic Field Induced Inter-Valley Trion Dynamics in Monolayer 2D Semiconductor

The valley polarization dynamics of excitonic states (excitons and trions) in monolayer (1L)-MoSe₂ under strong magnetic field are investigated. The experimentally observed magnetic-field-induced valley polarizations of trions (excitons) are analyzed by the rate equation model. It is found that the magnetic-field-induced valley polarizations are attributed to the asymmetric valley scattering of trions from K+ to K− valley and vice versa due to the degeneracy lifting of K+ and K− valleys by valley Zeeman effect under magnetic field. Moreover, the feeding of the valley-polarized excitons for trions formation and longer inter-valley scattering time reaching to a few nanoseconds at 10 K contribute to the larger valley polarization of trions than that of excitons in 1L-MoSe₂.     

Development of remotely operated unmanned boat with long-range Wi-Fi

Remotely monitored and operated unmanned vessels are effective for the working environment improvement of vessel crew, the solution of crew shortage, and the efficiency of marine survey. However, the development of unmanned vessels is delayed. One of factors is the communication problem. A bit rate of the current maritime communication using the satellite communication is about several hundred kbps from vessels. Therefore, this bit rate is insufficient for remote monitoring and operation. To solve this problem, a use of a long-range Wi-Fi communication is proposed. In this paper, the unmanned system capable of remote monitoring and operation with long-range Wi-Fi is developed and examined at Tokyo bay.     

Penetration Depth of Microwave into the Mixture of Goethite with Graphite Estimated by Permittivity and Conductivity

A study has been conducted to understand the penetration behavior of microwave into the mixture of goethite with carbon (C) aiming at providing an appropriate guidance to dehydrate the substances with hydroxides occasionally contained in industrial sludge. At first, it was observed that microwave could not sufficiently penetrate into the specimen with C/goethite molar ratios greater than 2, giving incomplete dehydration. To understand the penetration behavior of microwave, permittivity and conductivity were measured. Permittivity measurements were successfully made below 9 vol pct C. For carbon content greater than 8.56 vol pct C, the conductivity of the mixture abruptly increased by four orders of magnitude because of the occurrence of the conductivity percolation. Above 13.7 vol pct C close to an inflection point approximating 10 vol pct C, the mixture became sufficiently conductive. Transition from dielectric to conductive behavior occurred between 8.56 and 13.7 vol pct C. The Generalized Effective Medium approximation could satisfactorily express the variation of the conductivity values in the whole range of vol pct C measured. The penetration depth of microwave was determined by the above two measurements. It was found that penetration depth decreased with the increasing vol pct of C contained in the mixture specimen. Finally, guidance could be provided as for the blend ratio of C to treated material along with the size of a briquette or a pellet referring to the obtained relation between penetration depth and vol pct of C. Furthermore, it was proved that the numerical simulation was quite helpful to predict how microwave behaves in the mixture under given conditions.     

Microwave-induced substitutional-combustion reaction of Fe3O4/Al ceramic matrix porous composite

Microwave processing and substitutional-combustion reaction have been utilized to fabricate ceramic matrix porous composite from the thermite reaction of Fe3O4/Al system. Stoichiometric and mixtures with lower and over aluminum were tested. As this system was highly exothermic, the melting of reaction products and destruction the porous structure may occur. In order to avoid that, reaction coupled with a smaller driving force by controlling the microwave (MW) ignition condition at low temperature exotherm, where substitutional reaction occurs has been investigated. The phase and microstructure evolution during the reaction is analyzed by differential thermal analysis (DTA), X-ray diffraction (XRD), and scanning electron microscopy (SEM). Thermogram of the DTA analysis, irrespective of their mole ratio, recorded two exothermic peaks, one at ~1310 °C and another one at ~1370 °C. Fe and α-Al₂O₃ were the main products for the combusted mixture. Hercynite appeared as the major phase in the stoichiometric and slightly lower Al content mixtures due to incompleteness of reaction. In contrary, over aluminized mixture revealed the presence of Al_3.2Fe. When heated at 1360 °C, an additional FeO phase was observed. Mixtures with extremely low Al content showed the presence of unreacted Fe₃O₄ and some free Al due to the decrease of combustion velocity associated with a decrease in the sample exothermicities. Sample heated in electric furnace was dense. When heating by microwave, controlling the reaction progress at low temperature exotherm allowed the achievement of porous structure composite consisting of micron size iron particles well distributed and embedded in the hercynite and/or Al₂O₃ matrix.     

Molecule‐Induced Conformational Change in Boron Nitride Nanosheets with Enhanced Surface Adsorption

Surface interaction is extremely important to both fundamental research and practical application. Physisorption can induce shape and structural distortion (i.e., conformational changes) in macromolecular and biomolecular adsorbates, but such phenomena have rarely been observed on adsorbents. Here, it is demonstrated theoretically and experimentally that atomically thin boron nitride (BN) nanosheets as an adsorbent experience conformational changes upon surface adsorption of molecules, increasing adsorption energy and efficiency. The study not only provides new perspectives on the strong adsorption capability of BN nanosheets and many other two‐dimensional (2D) nanomaterials but also opens up possibilities for many novel applications. For example, it is demonstrated that BN nanosheets with the same surface area as bulk hexagonal BN particles are more effective in purification and sensing.     

Effect of sedimentary facies and geological properties on thermal conductivity of Pleistocene volcanic sediments in Tokyo,central Japan

When ground source heat pump systems are installed underground, an estimate of the thermal conductivity is required to determine the desired total length of the heat exchanger (U-tube). Many large cities in Asia are built on Quaternary sediments, but the thermal conductivity of these sediments is not well understood. To measure the thermal conductivity of Pleistocene volcanic sediments in Tokyo, Japan, we discuss methods of measuring thermal conductivity and factors influencing the thermal conductivity of volcanic sediment, which has low quartz content. The results obtained from experiments using a drill core, borehole data and artificial sediment samples are as follows: (1) values of thermal conductivity predicted using water content, porosity or sand content can be underestimated in volcanic sediment or sediments with large amounts of magnetic minerals; (2) magnetic minerals have a higher thermal conductivity than quartz, so there is a relationship between magnetic susceptibility and thermal conductivity: (3) comparison of thermal conductivity measurements performed using box- and needle-type probes showed that the values measured using the former are comparatively larger. This decrease in thermal conductivity is explained by formation of air-filled cracks when the needle penetrates the sediment, as air has a lower thermal conductivity than sediment.