A shaE deletion mutant showed lower Na+ sensitivity compound to other deletion mutants in the Bacillus subtilis sodium/hydrogen antiporter (Sha) system

The sodium/hydrogen antiporter (Sha, identical to multiple resistance and pH adaptation: Mrp) encoded by shaABCDEFG is considered to be the major Na+ excretion system in Bacillus subtilis. We constructed deletion mutants of each sha (=mrp) gene and found that a shaE mutant showed lower Na+ sensitivity compared to the other mutants with respect to the growth, sporulation and Na+ efflux activity. ShaE may have a dissimilar role to other Sha proteins in transport functions.     

An approach to data fusion using uncertain knowledge in geographical information systems

Digital terrain maps have become widespread, and Geographical Information Systems (GIS) have moved into the limelight. One of the key technologies needed in GIS is data fusion reasoning. The function of data fusion is to consider various geographical data, such as “roads” and “slope,” and make a complete evaluation. In this paper, we propose a data fusion reasoning technology using uncertain knowledge. Data fusion knowledge contains some uncertainty. For example, our knowledge for evaluating mobility costs is uncertain because it is qualitative, such as “we want to refuse steep places.” We introduced two uncertainty reasoning mechanisms to represent such data fusion process. One is fuzzy reasoning, and the other is Dempster–Shafer theory. We also offer knowledge‐editing facilities for describing data fusion knowledge, such as a data flow diagram editor for designing data fusion process and a membership function editor for describing data abstraction methods. These knowledge editors facilitate the development and modification of data fusion knowledge base for GIS. © 1999 Scripta Technica, Electr Eng Jpn, 128(4): 65–76, 1999     

All‐Solid Actuator Consisting of Polyaniline Film and Solid Polymer Electrolyte

An all‐solid actuator, consisting of a polyaniline (PANI) film and a solid polymer electrolyte (SPE) of poly(ethylene oxide) derivative (STO288), clearly showed a reversible displacement in an atmosphere when a voltage was applied between the PANI film and the SPE layer. The displacement and the response rate are mainly dependent on the applied voltage and the employed supporting salt, but are influenced by the humidity and temperature of the environment. The results of the present experiments have revealed that the influences of the humidity and temperature on the performance of the actuator are predominantly through the ionic conductivity of the SPE.

All‐solid actuator consisting of PANI and SPE.     

Stabilization of lysozyme against irreversible inactivation by alterations of the Asp-Gly sequences

Site-directed mutagenesis was performed at Asp-Gly (48–49,66–67, 101–102) and Asn-Gly (103–104) sequencesof hen egg-white lysozyme to protect the enzyme against irreversiblethermoinactivation. Because the lysozyme inactivation was causedby the accumulation of multiple chemical reactions, includingthe isomerization of the Asp-Gly sequence and the deamidationof Asn [Tomizawa et al.(1994) Biochemistry, 33, 13032–13037],the suppression of these reactions by the substitution of Glyto Ala, or the introduction of a sequence of human-type lysozyme,was attempted and the mutants (where each or all labile sequenceswere replaced) were prepared. The substitution resulted in thereversible destabilization from 1 to 2 kcal/mol per substitution.The destabilization was caused by the introduction of ß-carbonto the constrained position that had conformational angles withinthe allowed range for the Gly residue. Despite the decreasein the reversible conformational stability, the mutants hadmore resistance to irreversible inactivation at pH 4 and 100°C.In particular, the rate of irreversible inactivation of themutant, which was replaced at four chemically labile sequences,was the latest and corresponded to 18 kcal/mol of the reversibleconformational stability. Therefore, replacement of the chemicallylabile sequence was found to be more effective at protectingenzymes against irreversible thermoinactivation than at strengtheningreversible conformational stability.     

40-Gbit/s ETDM Channel Technologies for Optical Transport Network

We review recent progress and the future of 40-Gbit/s electrical time division multiplexed (ETDM) channel technologies for the optical transport network (OTN), where optical technologies, including high-speed ETDM channel transmission and wavelength division multiplexing (WDM), dramatically enhance network flexibility while reducing transport node cost as well as transmission cost. The 40 Gbit/s channel has recently been specified to be one of the optical channels in OTN. A new digital frame for the optical channels [optical channel transport unit (OTU)] was introduced for the network node interface of OTN in International Telecommunication Union-Telecommunication (ITU-T) standard. The specified data bit rates are 2.7 Gbit/s (OTU1), 10.7 Gbit/s (OTU2), and 43.0 Gbit/s (OTU3). These OTU frames have additional overhead bytes that support the network management overhead for OTN and out-of-band forward error correcting (FEC) codes. We discuss the feasibility and impact of the OTU3 frame in terrestrial networks. A newly developed 43-Gbit/s OTN line terminal prototype that confirms the feasibility of 43-Gbit/s ETDM channels and the OTU3 management capability is discussed. As a guide to the evolution of OTN, modulation formats for 43Gbit/s-based DWDM transmission are described for long distance application with the total capacity over one terabit per second.     

Spin‐Coated Highly Efficient Phosphorescent Organic Light‐Emitting Diodes Based on Bipolar Triphenylamine‐Benzimidazole Derivatives

A new series of star‐shaped bipolar host molecules, tris(4′‐(1‐phenyl‐1H‐benzimidazol‐2‐yl)biphen‐yl‐4‐yl) amine (TIBN), tris(2′‐methyl‐4′‐(1‐phenyl‐1H‐benzimida zol‐2‐yl)biphenyl‐4‐yl)amine (Me‐TIBN), and tris(2,2′‐dimethyl‐4′‐(1‐phenyl‐1H‐benzimidazol‐2‐yl)biphenyl‐4‐yl)amine (DM‐TIBN), that contain hole‐transporting triphenylamine and electron‐transporting benzimidazole moieties are designed based on calculations using density functional theory and successfully prepared. The theoretical calculation of energy levels of TIBN derivatives affords helpful ideas to design molecules with a favorable localization of highest occupied/lowest unoccupied molecular orbital (HOMO/LUMO) levels and a predefined enhancement of the triplet energy gap. The TIBN derivatives are employed as hosts to fabricate phosphorescent organic light‐emitting diodes (OLEDs) by the two methods of spin‐coating and vacuum deposition. Notably, the spin‐coated Me‐TIBN and DM‐TIBN devices exhibit a much better performance than the vacuum‐deposited ones, in which the spin‐coated DM‐TIBN device (47 500 cd m^?2, 27.3 cd A^?1, 7.3 lm W^?1) is outstanding with respect to other seminal work for solution‐processed OLEDs. More importantly, the new concept of localizing HOMO and LUMO levels for bipolar molecules is illustrated, and a facile strategy to tailor the energy levels by breaking the conjugation of hole‐ and electron‐transporting moieties is demonstrated.     

Studies on possibility for alleviation of lifestyle diseases by low-dose irradiation or radon inhalation

Our previous studies showed the possibility that activation of the antioxidative function alleviates various oxidative damages, which are related to lifestyle diseases. Results showed that, low-dose X-ray irradiation activated superoxide dismutase and inhibits oedema following ischaemia-reperfusion. To alleviate ischaemia-reperfusion injury with transplantation, the changes of the antioxidative function in liver graft using low-dose X-ray irradiation immediately after exenteration were examined. Results showed that liver grafts activate the antioxidative function as a result of irradiation. In addition, radon inhalation enhances the antioxidative function in some organs, and alleviates alcohol-induced oxidative damage of mouse liver. Moreover, in order to determine the most effective condition of radon inhalation, mice inhaled radon before or after carbon tetrachloride (CCl(4)) administration. Results showed that radon inhalation alleviates CCl(4)-induced hepatopathy, especially prior inhalation. It is highly possible that adequate activation of antioxidative functions induced by low-dose irradiation can contribute to preventing or reducing oxidative damages, which are related to lifestyle diseases.     

Iodine-aided fabrication of hollow carbon fibers from solid poly(vinyl alcohol) fibers

Hollow carbon fibers were fabricated from solid poly(vinyl alcohol) (PVA) fibers with the aid of an iodine pretreatment followed by stabilization. Iodination converted the chemical structure of PVA to polyene form due to dehydration reaction, and stabilization of heat treatment at 200 °C in air provided insolubilization of iodinated PVA fibers. These processes extremely enhanced the carbon yield and enabled to obtain intact carbon fiber. By selective iodination and subsequent stabilization within the fiber cross-section close to the fiber surface, hollow carbon fibers were made through the carbonization.