Overlapping positive and negative regulatory elements determine lens-specific activity of the delta 1-crystallin enhancer

Lens-specific expression of the delta 1-crystallin gene is governed by an enhancer in the third intron, and the 30-bp-long DC5 fragment was found to be responsible for eliciting the lens-specific activity. Mutational analysis of the DC5 fragment identified two contiguous, interdependent positive elements and a negative element which overlaps the 3'-located positive element. Previously identified ubiquitous factors delta EF1 bound to the negative element and repressed the enhancer activity in nonlens cells. Mutation and cotransfection analyses indicated the existence of an activator which counteracts the action of delta EF1 in lens cells, probably through binding site competition. We also found a group of nuclear factors, collectively called delta EF2, which bound to the 5'-located positive element. delta EF2a and -b were the major species in lens cells, whereas delta EF2c and -d predominated in nonlens cells. These delta EF2 proteins probably cooperate with factors bound to the 3'-located element in activation in lens cells and repression in nonlens cells. delta EF2 proteins also bound to a promoter sequence of the gamma F-crystallin gene, suggesting that delta EF2 proteins are involved in lens-specific regulation of various crystallin classes.     

Dynamic characteristics and dual control of a ball screw drive with integrated piezoelectric actuator

This paper describes the precision continuous path tracking control by using a dual-actuated single stage. First, fine-drive mechanism and the dynamic model of the entire drive system are described. In the simulation model, the dynamic characteristic of the dual-actuated stage is investigated to see whether it can provide precise motion by using dual control. Second, the fine motion controller is designed. Adjusting the control parameters, a positioning resolution of 20 nm and a bandwidth of 260 Hz were obtained. Third, the frequency responses of coarse and fine drives are experimentally investigated. After that, the dual controller is designed based on the investigated dynamics. Finally, whether coarse motion and fine motion could work complimentarily by the dual servo is examined in the experiments. By using the simultaneous dual controller, tracking errors were reduced sufficiently compared to the single coarse control.     

Development of in-vessel components of the microfission chamber for ITER

Microfission chambers (MFCs) will measure the total neutron source strength in ITER. The MFCs will be installed behind blanket modules in the vacuum vessel (VV). Triaxial mineral insulated (MI) cables will carry signals from the MFCs. The joint connecting triaxial MI cables in the VV must be considered because the MFCs and the MI cables will be installed separately at different times. Vacuum tight triaxial connector of the MI cable has been designed and a prototype has been constructed. Performance tests indicate that the connector can be applied to the ITER environment. A small bending-radius test of the MI cable indicates no observed damage at a curvature radius of 100 mm.     

Quantitative and easy estimation of a crystal bending effect using low-order CBED patterns

The quantitative measurement of a crystal bending effect is performed using low-order zone-axis convergent beam electron diffraction (CBED) patterns. Although the accuracy of the present method is inferior to that of the method of using split higher order Laue zone lines, this method enables us to estimate the crystal bending effect at a region very close to the interface and to easily judge whether the crystal bending effect results in a tensile bend or a compressive bend. As an application of the present method, the crystal bending effect at a region close to the SiGe/Si interface was measured. It was found that the crystal bending effect is due to a thin-foil relaxation of almost 0.3 degrees at a region that is approximately 10 nm away from the interface.     

Development of lateral displacement sensor for real‐time detection of structural damage

We have developed a novel sensor that enables us to measure the relative story displacement of a building structure in real time. This lateral displacement sensor (LDS) is composed of a light‐emitting diode (LED) array, which is fixed on the ceiling, and a position‐sensitive detector (PSD) unit, which is placed on the floor. We optimized the LDS to achieve high accuracy in lateral displacement measurement. The accuracy was evaluated to be 60 µm by conducting shaking table tests. Two LDSs were implemented in an actual building equipped with an active variable stiffness (AVS) system, and the building was vibrated with seismic waveforms by an exciter placed on the rooftop. The seismic displacement of the second floor relative to the first floor was measured using the LDS. Furthermore, the inclination angle of the second floor could be measured using the LDS during the seismic vibration. Using the AVS system, we realized the residual displacement of the second floor without inducing damage to the building, and succeeded in real‐time residual displacement measurement for the first time. These results indicate that the LDS is useful for the health diagnosis of a building structure. © 2011 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.     

Quantification of wear,strain and heat energy consumption rates for sliding steel ball against diamond-like carbon coatings

Abstract

In this work, we evaluated the different energy consumption rates associated with the total frictional energy for a ball sliding on a flat surface. The energy generated by the sliding two bodies in contact is dissipated into the materials in various forms. The wear consumption energy for a steel ball against a diamond-like carbon surface was evaluated by the wear coefficient of the wear volume–energy input equation. The strain energy generated in the steel ball as a result of being made to slide under a certain load was calculated using the Hertzian theory. The chemical reaction energy was estimated based on iron oxidation. Finally, the frictional energy dissipated as heat was obtained by subtracting the wear and the strain energies from the total frictional energy.     

Development of diamond-like carbon fibre wheel

The first author invented a unique diamond-like carbon (DLC) grinding wheel, in which the DLC fibres were made by rolling Al sheets coated with DLC films and aligned normally to the grinding wheel surface by laminating Al sheets together with DLC fibres [K. Yamaguchi, Y. Wei, M. Takeuchi, Development of DLC fibre grinding wheel, in: Proceedings of the Vernal Meeting of the JSPE, Tokyo, 16–18 March 1999, p. 260]. In this paper, the formation process of DLC fibres and the fabrication process of a DLC fibre wheel were investigated. Many grinding experiments were also carried out on a precision NC plane milling machine using a newly developed DLC wheel. Grinding of specimens of silicon wafers, optical glasses, quartz, granites and hardened die-steel SKD11 demonstrated the capabilities to nanometer surface finish. A smooth surface with a roughness value of Ra 2.5 nm (Ry 26 nm) was achieved.     

An improved method of phosphorus analysis in sea water

A reagent for the determination of phosphorus in sea water which contains Mo(VI) plus Mo(V) may be easily prepared by the reduction of Mo(VI) with metallic zinc in acid medium. This reagent is stable in the air for several months, and the development of the molybdenum blue colour is complete in 20 min at about 100°C; the colour is stable for at least a few months. The salt error is approximately 5 per cent with sea water of chlorinity 19 per milli. The interference due to either arsenate or silicate at their concentrations in sea water is negligible.     

Scanning electron microscopic structure of the prismatic layer in the Bivalvia

The shell structure of the Bivalvia has been observed with the use of optical and electron microscopes since the early 1900’s. The prismatic structure is one of the more attractive shell structures in bivalved mollusks. This structure is composed of the aggregation of polygonal prisms arranged densely. Each prism is made of small calcite crystallites arranged perpendicular to a growth shell surface. Organic materials, named organic sheaths, accumulate around prisms and stain well with heamatoxylin-eosin. The Bivalvia, which make prismatic structures, are divided into two groups. One group has the inner shell layer made up of a nacreous structure, and the other has the inner shell layer made up of a foliated structure. The aragonite prismatic layer and the prismatic layer are closely related to each other, as is the aragonite prismatic layer to the composite prismatic one.     

Effect of Oxygen Adsorbates on Terahertz Emission Properties of Various Semiconductor Surfaces Covered with Graphene

We have studied coherent terahertz (THz) emission from graphene-coated surfaces of three different semiconductors—InP, GaAs, and InAs—to provide insight into the influence of O₂ adsorption on charge states and dynamics at the graphene/semiconductor interface. The amplitude of emitted THz radiation from graphene-coated InP was found to change significantly upon desorption of O₂ molecules by thermal annealing, while THz emission from bare InP was nearly uninfluenced by O₂ desorption. In contrast, the amount of change in the amplitude of emitted THz radiation due to O₂ desorption was essentially the same for graphene-coated GaAs and bare GaAs. However, in InAs, neither graphene coating nor O₂ adsorption/desorption affected the properties of its THz emission. These results can be explained in terms of the effects of adsorbed O₂ molecules on the different THz generation mechanisms in these semiconductors. Furthermore, these observations suggest that THz emission from graphene-coated semiconductors can be used for probing surface chemical reactions (e.g., oxidation) as well as for developing O₂ gas sensor devices.