Status of the Electrostatic Levitation Furnace (ELF) in the ISS-KIBO

The electrostatic levitation method is a containerless processing technique that utilizes Coulomb force between a charged sample and the surrounding electrodes. The Japan Aerospace Exploration Agency (JAXA) has been developing this technique for more than 20 years. In 2016, JAXA completed the flight model assembly, and the Electrostatic Levitation Furnace (ELF) for the International Space Station (ISS) was launched to the ISS. The ELF is mainly intended to handle oxide melts that are difficult to levitate on the ground based electrostatic levitator due to gravity and due to insufficient charging. ISS-ELF can measure the thermophysical properties (density, surface tension and viscosity) of high temperature melts above 2000 ^°C. The thermophysical properties data of materials at high temperature is useful for the study of liquid states and improvement of numerical simulation by modeling the manufacturing processes using the liquid state. Moreover, the interfacial energy of immiscible melts will be measured by creating a core-shell droplet configuration which otherwise cannot be obtained on the ground due to sedimentation. This paper briefly describes the ELF facility and presents the results of a functional checkout that includes the density measurement of molten alumina.     

Preparation of Zirconia Coatings by Hydrolysis of Zirconium Alkoxide with Hydrogen Peroxide

Coatings of 8.8-mol%-yttria-doped zirconia were fabricated using a transparent and spinnable sol prepared by hydrolysis of zirconium alkoxide with hydrogen peroxide and nitric acid. The sol gave a crack-free coating film consisting of fine grains. The crystalline phase was cubic after heating at 1000° and 1200°C and cubic and tetragonal at 1350°C, with the coating being highly oriented in the (111) plane, especially at 1000°C. Activation energy of the coating films was higher than that of the bulk. Transmittance through a film thickness of about 0.3 μm on each side was 75%.     

Three-dimensional medical image analysis of the heart by the revised GMDH-type neural network self-selecting optimum neural network architecture

In this study, a revised group method of data handling (GMDH)-type neural network algorithm which self-selects the optimum neural network architecture is applied to 3-dimensional medical image analysis of the heart. The GMDH-type neural network can automatically organize the neural network architecture by using the heuristic self-organization method, which is the basic theory of the GMDH algorism. The heuristic self-organization method is a kind of evolutionary computation method. In this revised GMDH-type neural network algorithm, the optimum neural network architecture was automatically organized using the polynomial and sigmoid function neurons. Furthermore, the structural parameters, such as the number of layers, the number of neurons in the hidden layers, and the useful input variables, are selected automatically in order to minimize the prediction error criterion, defined as the prediction sum of squares (PSS).     

A Multiagent‐Based Microgrid Operation Method

In this paper, we propose an autonomous microgrid operation using a multiagent approach. The proposed multiagent system consists of seven types of agent: a single microgrid controller agent (MGC), several load agents (LAGs), several gas‐turbine (gas‐engine) agents (GAGs), several photovoltaic generation agents (PVAGs), several wind‐turbine generation agents (WTAGs), several battery agents (BAGs), and a single grid agent (GridAG). In a microgrid, LAGs act as consumers or buyers, GAGs, PVAGs, and WTAGs act as producers or sellers, and BAGs act as prosumers or sellers/buyers. In order to verify the performance of the proposed system, it is applied to a simple model system with different electrical power prices. From the simulation results, it can be seen that the proposed multiagent system can perform microgrid operations efficiently.     

Structure and formation of the twisted plywood pattern of collagen fibrils in rat lamellar bone

This study was designed to elucidate details of the structure and formation process of the alternate lamellar pattern known to exist in lamellar bone. For this purpose, we examined basic internal lamellae in femurs of young rats by transmission and scanning electron microscopy, the latter employing two different macerations with NaOH at concentrations of 10 and 24%. Observations after the maceration with 10% NaOH showed that the regular and periodic rotation of collagen fibrils caused an alternation between two types of lamellae: one consisting of transversely and nearly transversely cut fibrils, and the other consisting of longitudinally and nearly longitudinally cut fibrils. This finding confirms the consistency of the twisted plywood model. The maceration method with 24% NaOH removed bone components other than cells, thus allowing for three-dimensional observations of osteoblast morphology. Osteoblasts extended finger-like processes paralleling the inner bone surface, and grouped in such a way that, within a group, the processes arranged in a similar direction. Transmission electron microscopy showed that newly deposited fibrils were arranged alongside these processes. For the formation of the alternating pattern, our findings suggest that: (1) osteoblasts control the collagen fibril arrangement through their finger-like process position; (2) osteoblasts behave similarly within a group; (3) osteoblasts move their processes synchronously and periodically to promote alternating different fibril orientation; and (4) this dynamic sequential deposition of fibrils results in the alternate lamellar (or twisted plywood) pattern.     

Miniature spherical motor using iron–gallium alloy (Galfenol)

We propose a miniature spherical motor using iron–gallium alloy (Galfenol). This motor consists of four rods of Galfenol with square cross-section, a wound coil, a permanent magnet, an iron yoke and a spherical rotor placed on the edge of the rods. The magnetomotive force of the magnet provides bias magnetostriction for the rods and an attractive force that maintains the rotor on the rods. When currents of 180° phase difference flow in pairs of opposing coils, a torque is exerted on the rotor by pushing (expansion) and pulling (contraction) of the rods. Rotation about a single axis is realized by a sawtooth current, such that the rotor rotates with slow expansion and slips at the rapid contraction. The motor can be fabricated at small sizes and driven with a low voltage, suitable for application as a microactuator for rotating the camera and mirror in endoscopes.     

Effect of matrix particle size on texture development in SrBi<Subscript>4</Subscript>Ti<Subscript>4</Subscript>O<Subscript>15</Subscript> made by templated grain growth

Textured SrBi₄Ti₄O₁₅ (SBT) ceramics were fabricated by the templated grain growth process to examine the effect of matrix particle size on texture development and densification. Texture was developed by the shape change of matrix grains from equiaxed to platelike and the alignment of their plate face parallel to that of template grains. The matrix particle size determined the number of platelike matrix grains with right orientation, and an increase in the matrix particle size increased the number of misoriented grains. Misoriented grains formed large pores, resulting in a low sintered density. It was concluded that small matrix particles were favorable for preparing dense, highly textured SBT ceramics.     

Detection of superoxide anion radical in a stratum corneum intercellular lipid model using an electrochemical sensor

A stratum corneum intercellular lipid model was prepared in a quasi-non-aqueous system. It was found that the detection of the superoxide anion radical (O???) generated in the lipid model by ultraviolet (UV) irradiation was possible using an electrochemical O??? sensor. The use of an electron spin resonance-spin trap method confirmed that the reactive oxygen species generated in the lipid model by UV irradiation was O???; the presence of a hydroxyl radical (?OH) was also proven. In addition, a reduction in the electric current in the O??? sensor was observed in lipid models containing added antioxidants such as d-α-tocopherol and β-carotene. Moreover, there was a correlation between the degree of oxidative degradation of the lipid, which was determined by the thiobarbituric acid method, and the electric current due to the O??? detected using the O??? sensor.     

N-(18-Hydroxylinolenoyl)-l-Glutamine: A Newly Discovered Analog of Volicitin in Manduca sexta and its Elicitor Activity in Plants

Plants attacked by insect herbivores release a blend of volatile organic compounds (VOCs) that serve as chemical cues for host location by parasitic wasps, natural enemies of the herbivores. Volicitin, N-(17-hydroxylinolenoyl)-l-glutamine, is one of the most active VOC elicitors found in herbivore regurgitants. Our previous study revealed that hydroxylation on the 17th position of the linolenic acid moiety of N-linolenoyl-l-glutamine increases by more than three times the elicitor activity in corn plants. Here, we identified N-(18-hydroxylinolenoyl)-l-glutamine (18OH-volicitin) from larval gut contents of tobacco hornworm (THW), Manduca sexta. Eggplant and tobacco, two solanaceous host plants of THW larvae, and corn, a non-host plant, responded differently to this new elicitor. Eggplant and tobacco seedlings emitted twice the amount of VOCs when 18OH-volicitin was applied to damaged leaf surfaces compared to N-linolenoyl-l-glutamine, while both these fatty acid amino acid conjugates (FACs) elicited a similar response in corn seedlings. In both solanaceous plants, there was no significant difference in the elicitor activity of 17OH- and 18OH-volicitin. Interestingly, other lepidopteran species that have 17OH-type volicitin also attack solanaceous plants. These data suggest that plants have developed herbivory-detection systems customized to their herbivorous enemies.