Effect of gas evolution at solid-liquid interface on contact angle between liquid Si and SiO2

The contact angle between liquid Si and SiO₂ was measured with the sessile drop method at 1723 K. The contact angle changed very unusually due to the evolution of SiO gas at the solid/liquid interface. It was found that the real contact angle between liquid Si and SiO₂ is about 80° or less at 1723 K though the apparent contact angle of 95° was observed for a long time during the experiment. The difference in the contact angle can be explained with a model of a composite material. Although the real contact angle is more important in a physical point of view, the apparent contact angle should be adopted in some cases such as simulation works.     

SAKURA-viewer: intelligent order history viewer based on two-viewpoint architecture.

We propose a new intelligent order history viewer applied to consolidating and visualizing data. SAKURA-viewer is a highly effective tool, as: 1) it visualizes both the semantic viewpoint and the temporal viewpoint of patient records simultaneously; 2) it promotes awareness of contextual information among the daily data; and 3) it implements patient-centric data entry methods. This viewer contributes to decrease the user's workload in an order entry system. This viewer is now incorporated into an order entry system being run on an experimental basis. We describe the evaluation of this system using results of a user satisfaction survey, analysis of information consolidation within the database, and analysis of the frequency of use of data entry methods.     

An off‐line design method of compensation law for constrained linear systems

This paper deals with a design method of compensation law for linear constrained systems. By employing singular value decomposition of linear systems, we provide a design method of compensation law which fulfils system constraints. The feature of resulting compensation law is illustrated with numerical examples. Copyright © 2007 John Wiley & Sons, Ltd.     

Hydrogen recovery from cyclohexane as a chemical hydrogen carrier using a palladium membrane reactor

A palladium membrane reactor was applied to recover the hydrogen from cyclohexane as one of the promising chemical hydrogen carriers. The operation conditions of the palladium membrane reactor to obtain a higher hydrogen recovery were predicted by computer simulation. As a result, it was shown that the hydrogen recovery rate becomes higher as the pressure on the hydrogen permeation side is lowered below atmospheric pressure or as the reaction pressure increases. This was confirmed experimentally. As the perm-side pressure was lowered, the conversion as well as the hydrogen recovery rate at 573 K was found to increase. About 80% of the hydrogen contained in cyclohexane, depending on the operation condition was successfully recovered.     

Performance of calcium deficient hydroxyapatite–polyglycolic acid composites: an in vitro study

The strategic incorporation of bioresorbable polymeric additives to calcium-deficient hydroxyapatite cement may provide short-term structural reinforcement and modify the modulus to closer match bone. The longer-term resorption properties may also be improved, creating pathways for bone in-growth. The aim of this study was to investigate the resorption process of a calcium phosphate cement system containing either in polyglycolic acid tri-methylene carbonate particles or polyglycolic acid fibres. This was achieved by in vitro aging in physiological conditions (phosphate buffered solution at 37°C) over 12 weeks. The unreinforced CPC exhibited an increase in compressive strength at 12 weeks, however catastrophic failure was observed above a critical loading. The fracture behaviour of cement was improved by the incorporation of PGA fibres; the cement retained its cohesive structure after critical loading. Gravimetric analysis and scanning electron microscopy showed a large proportion of the fibres had resorbed after 12 weeks allowing for the increased cement porosity, which could facilitate cell infiltration and faster integration of natural bone. Incorporating the particulate additives in the cement did not provide any mechanism for mechanical property augmentation or did not demonstrate any appreciable level of resorption after 12 weeks.     

A rolled sheet of collagen gel with cultured Schwann cells: Model of nerve conduit to enhance neurite growth

We prepared a rolled sheet of collagen gel with cultured mouse Schwann cells (SCs) as a nerve conduit (a medical device for neurosurgeons to repair an injured peripheral nerve). PC12 cells and dorsal root ganglion (DRG) cells were used as neuronal cells for evaluating the neurite growth-promoting activity of the device. As a control, we compared the rolled device with a rod device. Those neuronal cells inoculated at the terminal part of the rolled device migrated into the central part along the inter-layer space of the collagen gel layer, and then differentiated into neurons, extending many neurites for 3–12 days in culture. Significantly, this migration of neuronal cells into the device and their subsequent neurite growth was not observed in the absence of the SCs. We conclude that our rolled sheet of collagen gel with SCs was well designed and very effective to promote neurite growth, and is a promising candidate for the nerve conduit.     

Corrosion of Al-Sn-Bi alloys in alcohol at high temperatures. Part I: Effects of the metallurgical structure of the alloys and the metal salt additions to alcohol

Corrosion of free machining Al alloys that contain Sn and Bi was investigated at 391-415 K in 2-(2-(2-methoxyethoxy)ethoxy)ethanol (MEEE) and 2-(2-(2-butoxyethoxy)ethoxy)ethanol (BEEE) with/without SnCl₂, Sn(OC₂H₅)₄, FeCl₃, and CuCl₂. The Al-Sn-Bi alloy displayed severe pitting corrosion in MEEE similar to the Al-Sn alloy in BEEE at 415 K, and Sn and Sn/Bi were enriched on the surface of pits. Immersion tests of pure Al in MEEE containing Sn/Cu-salts at 415 K also showed severe corrosion and the deposition of metallic Sn and Cu on the surface. The corrosion mechanisms are discussed in terms of the electro-catalytic activity of the Sn enriched on the surface.     

Development of long range optical fiber sensors for compositesubmarine power cable maintenance

Long range optical fiber sensors for power cable maintenance have been incorporated into a newly developed 500 kV DC submarine power cable. Optical fibers are used for a distributed temperature sensor and a mechanical damage sensor. The distributed temperature sensor provides data on temperature at distances up to 30 km, and the mechanical damage sensor locates external damage points on the submarine cable. After each characteristic was investigated, optical fiber sensors were incorporated on the submarine power cable. This composite cable was evaluated by various mechanical tests. The results were satisfactory and showed the composite cable to be of practical use. This new approach of incorporating optical fiber sensors in the cable structure brings a new sophistication and reliability to cable maintenance     

Jijo-2: an office robot that communicates and learns

Describes how the authors have combined speech recognition, dialogue management, and statistical learning procedures to develop Jijo-2; an office robot that can communicate with humans and learn about its environment.     

Gene transfer of human prostacyclin synthase prevents neointimal formation after carotid balloon injury in rats

BACKGROUND AND PURPOSE: A disordered proliferative process in the vascular wall is thought to underlie the pathogenesis of restenosis after percutaneous transluminal angioplasty and carotid endarterectomy. A growth inhibitory property of overexpressed prostacyclin (PGI2) synthase (PGIS) was recently implicated in the pathological proliferation of vascular smooth muscle cells (VSMC) in vitro. Here, we investigated the effects of increased PGI2 synthesis on the pathological proliferation of VSMCs. METHODS: The cDNA encoding human PGIS was transfected into endothelium-denuded rat carotid arteries after arterial balloon injury with the use of hemagglutinating virus Japan (HVJ). HVJ liposome vector complex without PGIS cDNA was used for vehicle control. The level of 6-keto PGF1alpha, a stable hydrolyzed metabolite of PGI2, the histological distribution of the immunoreactivity for human PGIS and the ratio of neointimal/medial area were analyzed. RESULTS: In the analyses of 6-keto PGF1alpha, the level in the carotid arteries was significantly elevated 3 days after PGIS expression-vector transfection compared with that in the arteries after vehicle transfection. Seven days after human PGIS expression-vector transfection, the PGIS cDNA-transfected neointimal cells were strongly positive for human PGIS immunoreactivity in 81% sections examined. Fourteen days after the injury, the ratio of neointimal/medial area was 1.2+/-0.4 in the PGIS expression-vector transfected group, which was significantly smaller than that of the vehicle control group, 1.7+/-0.5; P<0.01. CONCLUSIONS: It was thus demonstrated that the gene transfer of human PGIS expression-vector into rat carotid arteries resulted in the increased production of human PGI2 in the vascular wall, the expression of human PGIS in the developing neointima and significantly inhibited the neointimal formation generated after balloon injury.