Synthetic Collagen-like Polymer That Undergoes a Sol–Gel Transition Triggered by O–N Acyl Migration at Physiological pH

We previously reported an artificial collagen gel that can be used as a cell-culture substrate by end-to-end cross-linking of collagen-like triple-helical peptides via disulfide bonds. However, the gel had to be formed a priori by polymerizing the peptide in an acidic solution containing dimethyl sulfoxide for several days, which prevented its use as an injectable gel or three-dimensional (3D) scaffold for cell culture. In this study, we developed a collagen-like peptide polymer by incorporating an O–N acyl migration-triggered triple helix formation mechanism into a collagen-like peptide, which formed a gel within 10 min. We demonstrated that the collagen-like peptide polymer can be used as a 3D cell scaffold and that the 3D structure formation of cells can be controlled by collagen-derived bioactive sequences introduced into the peptide sequence.     

Independent Reinforced Soil Structure with Pile Foundation—Piled Geo-Wall: An Experimental Study on the Application to Seismic Measure for Embankment—

Our aim in this study was to achieve an independent reinforced soil structure with pile foundation that can be applied to such structures as earth retaining walls and countermeasures against the collapse of embankments or rockfall impact built on narrow construction sites, such as on slopes. In order to confirm the effectiveness of the application of pile foundation to reinforced soil structures by geogrid for improvement of the lateral resistance of the structure and to investigate the interaction between pile and reinforced soil structure, a dynamic centrifuge model test (25 G) was carried out. Two geogrid reinforced soil, one with piles and one without, were used in a countermeasure to reduce the deformation of a road embankment built on a slope in the event of an earthquake, and the effectiveness of the pile foundation to the reinforced soil structure was considered with regard to it affected the road surface. The details and the results of the dynamic centrifuge model test, as well as the interaction between pile and reinforced soil structure are described, and the effectiveness of the application of pile foundation to reinforced soil structure is discussed in this paper.     

Multiple calibration decomposition analysis: Energy use and carbon dioxide emissions in the Japanese economy, 1970–1995

The purpose of this paper is to present a new approach to evaluating structural change of the economy in a multisector general equilibrium framework. The multiple calibration technique is applied to an ex post decomposition analysis of structural change between periods, enabling the distinction between price substitution and technological change to be made for each sector. This approach has the advantage of sounder microtheoretical underpinnings when compared with conventional decomposition methods. The proposed technique is empirically applied to changes in energy use and carbon dioxide (CO₂) emissions in the Japanese economy from 1970 to 1995. The results show that technological change is of great importance for curtailing energy use and CO₂ emissions in Japan. Total CO₂ emissions increased during this period primarily because of economic growth, which is represented by final demand effects. On the other hand, the effects such as technological change for labor or energy mitigated the increase in CO₂ emissions.     

Numerical study on an equivalent source model for inhomogeneous magnetic field dosimetry in the low-frequency range

A new equivalent numerical source model is proposed for efficient dosimetric investigations in the low-frequency range. This approach allows the reproduction of complicated inhomogeneous magnetic field distributions around electronic appliances with full generality (i.e., supports three-dimensional vector fields). This paper investigates the accuracy of the equivalent source model using the geometry-based numerical reference model of a current loop to simulate the magnetic field distribution of a real electronic appliance. Good agreement between the equivalent source model and the reference is obtained with regard to the magnetic field distribution and the induced electric current density in a homogeneous human body model, respectively.     

Low-frequency dosimetry of inhomogeneous magnetic fields using the coil source model and the household appliance

In this paper, the magnetic field properties and the dosimetry at ELF (50 Hz) are investigated using a coil model, which is prescribed in the European standard EN50366 (CENELEC) as a substitute source model for real household appliances. The accuracy of magnetic field vectors and values of the induced current density, which is achieved with the coil model, were compared with the results of two test appliances (a drilling machine and a hand mixer) obtained from the equivalent source model. It was demonstrated that the magnetic fields obtained (dominant component and strength) using the coil model and the real appliance show an agreement with each other with a maximum difference of 5 dB. The calculated induced current densities in the numerical human body models (homogeneous and anatomical body models) and the real appliances also show a good agreement with each other with a maximum difference by a factor of 1.6 (by the anatomical body model). Furthermore, the values of both field vectors and induced current density values calculated using the coil model were shown to be higher than those calculated in the case of the real appliances. Based on these results, the applicability of the coil model prescribed in EN50366 confirms that of the two applied test appliances.     

Electrospinning processed nanofibrous TiO(2) membranes for photovoltaic applications

We have recently fabricated dye-sensitized solar cells (DSSCs) comprising nanofibrous TiO(2) membranes as electrode materials. A thin TiO(2) film was pre-deposited on fluorine doped tin oxide (FTO) coated conducting glass substrate by immersion in TiF(4) aqueous solution to reduce the electron back-transfer from FTO to the electrolyte. The composite polyvinyl acetate (PVac)/titania nanofibrous membranes can be deposited on the pre-deposited thin TiO(2) film coated FTO by electrospinning of a mixture of PVac and titanium isopropoxide in N,N-dimethylformamide (DMF). The nanofibrous TiO(2) membranes were obtained by calcining the electrospun composite nanofibres of PVac/titania as the precursor. Spectral sensitization of the nanofibrous TiO(2) membranes was carried out with a ruthenium (II) complex, cis-dithiocyanate-N,N(')-bis(2,2(')-bipyridyl-4,4(')-dicarboxylic acid) ruthenium (II) dihydrate. The results indicated that the photocurrent and conversion efficiency of electrodes can be increased with the addition of the pre-deposited TiO(2) film and the adhesion treatment using DMF. Additionally, the dye loading, photocurrent, and efficiency of the electrodes were gradually increased by increasing the average thickness of the nanofibrous TiO(2) membranes. The efficiency of the fibrous TiO(2) photoelectrode with the average membrane thickness of 3.9?μm has a maximum value of 4.14%.     

Electrical Nanocontact Between Bismuth Nanowire Edges and Electrodes

Three methods for attaching electrodes to a bismuth nanowire sample were investigated. In the first and second methods, thin layers of titanium and copper were deposited by ion plating under vacuum onto the edge surface of individual bismuth nanowire samples that were encapsulated in a quartz template. Good electrical contact between the electrodes and the nanowire was achieved using silver epoxy and conventional solder on the thin-film layers in the first and second methods, respectively. In the third method, a low-melting-point solder was utilized and was also successful in achieving good electrical contact in air atmosphere. The connection methods showed no difference in terms of resistivity temperature dependence or Seebeck coefficient. The third method has an advantage in that nanocontact is easily achieved; however, diffusion of the solder into the nanowire allows contamination near the melting point of the solder. In the first and second methods, the thin-film layer enabled electrical contact to be more safely achieved than the direct contact used in the third method, because the thin-film layer prevented diffusion of binder components.     

Autonomous and distributed mobility management in mobile core networks

The 5th generation mobile and wireless communication systems are expected to accommodate exploding traffic, increasing number of devices, and heterogeneous applications driven by proliferation of IoT and M2M technologies. However, the centralized mobility management architecture in a current mobile core network would face critical problems such as excessive concentration of load on specific servers and considerable increase in C-plane overhead. To solve the problems we first consider a novel architecture of distributed mobility management in C-plane in the mobile core network, which employs virtualized mobility management entity called ADMMEs (Autonomous Distributed Mobility Management Entity) in this paper. In addition, to assign an appropriate ADMME to a UE in accordance with mobility characteristics of the UE and a management policy, we propose an autonomous and adaptive ADMME selection scheme. We adopt a biologically-inspired algorithm, called attractor selection, to accomplish adaptive selection taking into account multiple objectives. Through simulation experiments, we confirmed our proposal could accomplish more than 63 % performance improvement comparing to the current method from viewpoints of delay, load balancing, and C-plane overhead under a dynamic mobility scenario.     

Effects of NiO-loading on n-type GaN photoanode for photoelectrochemical water splitting using different aqueous electrolytes

n-type GaN photoanodes used for water splitting have stability problems. One means of resolving this is loading NiO catalyst on the n-type GaN surface. Aqueous electrolytes H₂SO₄, HCl, KOH, and NaOH are usually used for photoelectrochemical water splitting. However, suitable electrolytes for the NiO-loading on n-type GaN photoelectrode have not yet been evaluated. Therefore, we investigated the effects of changing electrolytes used for NiO-loading in this study. The photocurrent of NiO-loading on n-type GaN increased when KOH and NaOH electrolytes were used. In addition, the surfaces showed no corrosion after reaction when these electrolytes were used. However, the photocurrent was not stable using KOH electrolyte. Interestingly, stable photocurrent was observed with when the NaOH electrolyte was used. In the case of H₂SO₄, the photocurrent of GaN did not change with and without NiO. The surface morphologies became rough because of GaN corrosion, and NiO dissolved in the H₂SO₄ electrolyte.