Cover Image,Volume 69, Issue 3

The cover image is based on the Mini‐Review Well‐defined, environment‐friendly synthesis of polypeptides based on phosgene‐free transformation of amino acids into urethane derivatives and their applications by Takeshi Endo et al., https://doi.org/10.1002/pi.5952 . Cover image © Takeshi Endo Images.

     

Applications of computer and numerical analysis techniques in welding research

In recent years, computer technology has made remarkable progress and a computer has become an indispensable tool for both engineers and scientists. In this article, utilization of computers in welding research is briefly summarized. Their use in numerical analysis is particularly discussed and applied to physical phenomena in molten pool, hydrogen diffusion and residual stresses due to welding. A comparison is made between theoretical and experimental results.     

Prediction of spectral reflectance factor distribution of automotive paint finishes

It is necessary to determine the accurate reflectance of painted surfaces for the review of paint finishes by computer graphics (CG) before actual painting of the exterior color of automobiles, and for quality control during production and inspection processes. We have optimized a method for measuring reflectance by using a statistical technique. We have found that the reflectance of a painted surface is best measured at an incident angle of 60° and at five aspecular angles of 10°, 18°, 28°, 40°, and 90°. Our method makes it possible to accurately reproduce reflection characteristics of paint finishes containing special flake pigments, such as pearl mica. Also it was proved that our method can apply not only to solid and metallic coatings but to all painted surfaces. © 2005 Wiley Periodicals, Inc. Col Res Appl, 30, 275–282, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/col.20125     

Electron transport in InGaO3(ZnO)m (m=integer) studied using single-crystalline thin films and transparent MISFETs

We have investigated the characteristics of transparent metal-insulator-semiconductor field-effect transistors (MISFETs) fabricated using InGaO₃(ZnO)_m (m=integer) single-crystalline thin films as n-channel layers and amorphous alumina as gate insulator films. The MISFETs exhibit good characteristics such as insensitivity to visible light illumination, off-current as low as ∼1 nA with a positive threshold voltage of ∼3 V and on/off current ratio of 10⁵. The field-effect mobility increased from ∼1 to ∼10 cm² (V s)⁻¹ as the m-value increased. Room temperature Hall mobility also increased. However, unexpectedly these values were lower than the field-effect mobility. It is explained by existence of shallow localized state in the homologous compounds.     

Silica removal from Mokai, New Zealand, geothermal brine by treatment with lime and a cationic precipitant

Preliminary experiments using two chemicals (CaO, a quicklime, and a cationic nitrogen-bearing precipitant, EC-004) to remove silica from geothermal brine were undertaken at the Mokai geothermal plant, New Zealand. The brine was mixed with the reagent (CaO or EC-004). The reaction was studied from the start of the experiment (NRT, 0 min, no retaining time) and after 15 min (15RT) at 90 °C. The concentration of silica in the brine was initially 954 mg/l, and decreased linearly with increasing reagent concentration. When CaO is added, the silica concentration at 15RT was 200 mg/l lower than at NRT and became almost zero on addition of 1.5 g/l. In contrast, when EC-004 is added, the total silica concentration nearly reaches the solubility of amorphous silica at 90 °C. In order to prevent silica scaling in Mokai brines cooled to 90 °C, the CaO and EC-004 added should be individually adjusted to 0.5 g/l and 80 mg/l, respectively.     

Addition of cisapride shortens colonoscopy preparation with lavage in elderly patients

The major envelope protein, p35, of vaccinia virus (VV; strain LIVP) was purified by extraction from virions with the non-ionic detergent Nonidet P-40. The protein was cleaved with CNBr. Four homogeneous peptides were isolated and their N-terminal amino-acid (aa) sequences determined. A computer search of a protein sequence databank revealed complete identity of the determined sequences with aa 44-63, 144-149, 154-165 and 224-238 of ORF H3 of the HindIII-H fragment of the VV genome [Rosel et al., J. Virol. 60 (1989) 436-446]. Earlier, Gordon et al. [Virology 167 (1988) 361-369] determined that the p35 surface protein of VV strain IHD-W is encoded by the H6 gene. Muravlev et al. [Biopolymery i kletka 6 (1990) 83-89 (Russian)] deduced from their data that gene A2 encodes this prominent antigen. Taking into account this ambiguity, we cloned the genes H3, H6 and A2 in expression vectors, prepared the specific antisera against the expression products and conducted the immunochemical analysis of the recombinant and native VV-specific proteins. It has been established that the H6 codes for an early protein that is found only in the infected cell extracts, but is absent in mature virions. The immunodominant protein p35 of VV strain LIVP is encoded by the gene H3. The gene A2 protein product is present mainly in the infected cell extract, but the antiserum against the A2 product shows a rather weak interaction with the 35-kDa fraction of structural VV proteins resolved by electrophoresis.     

Development of 170 GHz/500 kW gyrotron

A development of 170GHz/500kW level gyrotron was carried out as R&D work of ITER. The oscillation mode is TE_31,8. In a short pulse experiment, the maximum power of 750kW was achieved at 85kV/40A. The efficiency was 22%. In the depressed collector operation, 500kW/36%/50ms was obtained. The maximum efficiency of 40% was obtained at P_RF=470kW whereas the power decrease by the electron trapping was observed. Pulse extension was done up to 10s at P_RF=170kW with the depressed collector operation. The power was limited by the temperature increase of the output window.     

Structures and functions of xenobiotic efflux pump P-glycoprotein and MRP--important molecular targets for cancer chemotherapy

This paper deals with the basic features of the xenobiotic efflux pump (P-glycoprotein and MRP) and the clinical significance of the search for specific modulators of these proteins. P-glycoprotein and MRP function as ATP-dependent efflux pumps that extrude cytotoxic drugs from the cells before the drugs reach their intracellular targets, thus conferring resistance to many structurally dissimilar anti-cancer drugs. These proteins are responsible for multidrug resistance of tumor cells, a major obstacle to cancer chemotherapy. To develop well-designed modulators, structural information regarding the specific drug binding sites is important. We recently found that mutations in the putative transmembrane domain (TM) 1 of human P-glycoprotein alter the drug resistance pattern. Some amino acid residues in TM1 together with TM5-6 and TM11-12 may help to govern substrate specificity. The features common to substrates for P-glycoprotein and MRP are also discussed.     

Inter- and intra-molecular ionic interactions of polyampholyte: Carboxymethyl-2-diethylaminoethylcellulose

Carboxymethyl-2-diethylaminoethylcellulose (CM-DEAE cellulose) was prepared by etherification of carboxymethylcellulose with diethylaminoethyl chloride in a NaOH solution. The behaviour of CM-DEAE cellulose in aqueous solution was studied by viscosity and GPC measurements. The degree of substitution (DS) and existing states of DEAE substituents were examined by the use of proton NMR, and those of the CM substituents were observed with FT-IR. The results reveal that the reduced viscosity and apparent molecular size of CM-DEAE cellulose vary with the concentration of sodium chloride and changes in pH and DS. These phenomena can be explained in terms of inter- and intra-molecular ionic interactions.