High-throughput, high-level production of PS-tag-fused single-chain Fvs by microplate-based culture

In the present study, we investigated a microplate-based culture (MBC) of Escherichia coli for the high-throughput, high-level production of PS-tag-fused scFvs (scFv-PS) in insoluble form. The Overnight Express™ Autoinduction System (OE system) was adopted to skip the laborious induction step of the addition of IPTG. ScFv and scFv-PS began to be expressed after 6 h by conventional flask culture (FLC) and by MBC when utilizing the OE system, and similar specific productivity levels were attained during cultivation. In MBC, an important factor that directly affected the production levels was rotational speed during cultivation, suggesting that the mass transfer of oxygen was rate-limiting. In a comparison of the productivity of flask cultures utilizing the 2YT-IPTG and OE systems, MBC utilizing the OE system was the highest, with approximately 1 mg of insoluble scFv-PS obtained from each well under optimal conditions (1400 rpm). The results of SDS-PAGE and a cross-contamination check indicated that very similar cultivation conditions were attained in each well, without cross-contamination. Thus, MBC using the OE system is very useful for the high-throughput, high-level production of scFv-PS, which can be activated on the surface of hydrophilic PS plates by solid-phase refolding. Therefore, the production of a variety of specific scFv-PSs for cytokines and biomarkers will make possible the construction of sensitive and low-cost antibody microarrays, which will be very useful in clinical diagnosis and biochemical research.     

Site-Investigation and Geotechnical Design of D-Runway Construction in Tokyo Haneda Airport

Tokyo International Airport (Haneda Airport) is a domestic hub-airport in Japan; however, the increasing number of passengers has brought it close to its capacity. In addition, there has been strong demand for the development of an international-flight network. Consequently, a new runway, called the “D-runway,” was planned and constructed from March 2007 to October 2010. Because some of the D-runway runs through a river mouth, a hybrid structure consisting of piled pier and reclamation fill was adopted. To overcome the geotechnical difficulties in constructing this hybrid structure on the soft clay deposit, various technologies in design and construction were adopted. This paper provides an outline of the project, the ground investigation, and the design of the D-runway structure from a geotechnical engineering view point. From the results of the site investigation, the stratigraphic model at the site was clarified. For the clay layers, a representative depth-profile for each soil parameter was determined. Some local soil properties which tended to be overlooked when only employing an engineering point of view can be appropriately captured by linking the geological and geotechnical information. In the construction of the D-runway, not only the ground improvement technologies (SD, SCP, and CDM) but also the new developed construction materials (the pneumatic mixing of cement treated soil and air-foam treated lightweight soil) were utilized. In the-D-runway project, various technologies used in previous airport constructions were brought together and applied to the ground investigation, design, construction work, and even maintenance. The construction of the D-runway was completed safely, rapidly, and economically, and it came into use on 21 October 2010, on schedule.     

The Influence of Dry-Milled Wood Flour on The Physical Properties of Wood Flour/Polypropylene Composites

In this study, we evaluated the influence of wood flour (particle size: <90 μm) on the physical properties of wood flour/polypropylene (PP) composites. Wood flour was obtained by dry ball-milling of forest-thinning material at a rotary speed of 250 rpm for 1, 2, 4, and 8 h. The milled wood flour was filtered using a 90 μm sieve. The water content of the wood flour was adjusted to 5, 10, or 20 wt%. Composite properties, including mechanical properties, water absorption, and thermal expansion, were evaluated at wood flour loadings of 40 wt%. When wood flour with 5 wt% water content was milled for 2 and 4 h, the resulting wood flour was granular rather than fibrous; flocculation of the fine particles was observed for milling times exceeding 4 h. This morphological change in the wood flour reduced its influence on the physical properties of the composites, although some positive influences were observed on the molding properties of the composite, such as an increase in compound fluidity. Milled wood flour with 10 wt% or 20 wt% water content was fibrous. Scanning electron microscopy observation of milled wood flour with 10 wt% water content revealed partial surface fibrillation at widths of tens to hundreds of nanometers. The addition of wood flour with nanoscale surface fibrils to PP composites positively influenced the properties of the composite, resulting in a decrease in the linear coefficient of thermal expansion in the flow direction.     

Increased Water Resistance of Bamboo Flour/Polyethylene Composites

Abstract

To improve the water resistance of bamboo flour/high-density polyethylene (HDPE) composites, the effects of plastic content, coupling agents, and the addition of micro-fibrillated cellulose (MFC) on formulations were studied, and their rheological and mechanical properties were evaluated. The composites were prepared by injecting molding with a basic composition of equivalent amounts of bamboo flour and HDPE, and the melting fluidity of the compounds, tensile strength, and tensile modulus of the composites were determined. An increase in water resistance was detected in all three tests. By increasing the plastic content, negative effects such as a decreased tensile modulus were observed. When evaluating the compatibility between bamboo flour and plastic using coupling agents and MFC addition, positive effects were noted for water resistance, melting fluidity, and tensile modulus. We also confirmed that the procedure used to increase the compatibility between bamboo flour and plastic could easily be used for industrial applications by changing the coupling agents. Overall, a novel positive property (increased tensile modulus) and an increased water resistance were observed after MFC addition.     

Selective hydroxylation of benzene to phenol by photocatalysis of molybdenum complexes grafted on mesoporous FSM‐16

Mo complexes with Mo₁–Mo₄ nuclearities were grafted on mesoporous silica FSM‐16, and their catalytic performances were studied in the hydroxylation of benzene. A trinuclear Mo oxo complex grafted on FSM‐16 exhibits the highest catalytic activity in the hydroxylation of benzene to phenol using hydrogen peroxide as an oxidant under the irradiation of UV‐light. The turnover numbers for phenol are over 700 at 300 K. This revised version was published online in July 2006 with corrections to the Cover Date.     

14-GHz band 1 watt GaAs f.e.t. amplifier

A 14.0?14.5 GHz 1 W amplifier using 0.5 ?m gate length power GaAs f.e.t.s has been developed. The amplifier, consisting of a cascade of three single-ended stages, realises 13 dB small-signal gain, 1.1 W output-power saturation and 39 dBm third-order intermodulation intercept. The circuit design and the microwave performance of the amplifier are discussed.     

Cathodic polarization curves of the oxygen reduction reaction on various structural materials of boiling water reactors in high temperature–high purity water

Cathodic polarization curves of the O₂ reduction reaction were measured by using electrodes made from typical structural materials of boiling water reactors (BWRs) to evaluate the effects of kind of material on the electrochemical corrosion potential (ECP) calculation. To estimate ECPs at any region in the BWRs on the basis of the BWR environmental conditions, anodic and cathodic polarization curves should be obtained in advance under relevant conditions. The concentration of oxidants such as O₂ and H₂O₂ in coolant changes depending on the region in which they exist. As well, reduction reaction rates might differ depending on the kind of materials. In this work, the cathodic polarization curves of type 316L stainless steel (316L SS) and Alloy 182 were measured in high purity water at 553 K with different O₂ concentrations and compared with those of type 304 SS (304 SS). The results showed that the cathodic polarization curves differed depending on the kind of materials at the activation-controlled region. But, the difference in the ECP vs. O₂ concentration relationship was small when the ECPs were calculated by using both anodic and cathodic polarization curves measured on the objective material.     

Numerical simulation using CFD software of countercurrent gas-liquid flow in a PWR hot leg under reflux condensation

In order to improve the countercurrent flow model of a transient analysis code, countercurrent air-water tests were previously conducted using a 1/15 scale model of the PWR hot leg and numerical simulations of the tests were carried out using the two-fluid model implemented in the CFD software FLUENT 6.3.26. The predicted flow patterns and CCFL characteristics agreed well with the experimental data. However, the validation of the interfacial drag correlation used in the two-fluid model was still insufficient, especially regarding the applicability to actual PWR conditions. In this study, we measured water levels and wave heights in the 1/15 scale setup to understand the characteristics of the interfacial drag, and we considered a relationship between the wave height and the interfacial drag coefficient. Numerical simulations to examine the effects of cell size and interfacial drag correlations on numerical predictions were conducted under PWR plant conditions. Wave heights strongly related with the water level and interfacial drag coefficient, which indicates that the interfacial drag force mainly consists of form drag. The cell size affected the gas velocity at the onset of flooding in the process of increasing gas flow rate. The gas volumetric fluxes at CCFL predicted using fine cells were higher than those using normal cells. On the other hand, the cell size did not have a significant influence on the process of decreasing gas flow rate. The predictions for the PWR condition using a reference set of interfacial drag correlations agreed well with the Upper Plenum Test Facility data of the PWR scale experiment in the region of medium gas volumetric fluxes. The reference interfacial drag correlations employed in this study can be applied to the PWR conditions.     

A polymer complex as a new type of electron beam resist for dry development

Polymer complex of poly (4-vinylpyrldine) and malonic acid was investigated as a new type of electron beam (EB) resist for dry development, as malonic acid was decomposed by EB irradiation. It was found that the polymer complex could be developed with O₂ plasma etching and that the positive resist patterns with high resolution could be obtained. The mechanism for this lithography process was studied by means of IR and ESCA spectra.