An understanding of the age-related changes in the volume of the normal maxillary sinus will help to identify sinus abnormalities. Normal maxillary sinus volume was measured on axial CT scans in 115 cases, and analysed in relation to age, the presence of premolar and molar teeth, size of the midfacial skeleton and body height and weight. The volume ranged from 4.56-35.21 cm3 (mean: 14.71 +/- s.d. 6.33 cm3) in patients aged over 20 years. There was no significant sex difference and a close correlation between the two sides was found. The volume increased up to the age of 20 years, but then decreased. There was no significant difference in patients with and without maxillary premolars and molars between the ages of 50 and 79 years. The difference in right and left dentitions had no influence on the maxillary sinus volume over the age of 20 years. Adult maxillary sinus volume correlated with the interzygomatic buttress distance. In adult females, there was a significant correlation between the volume and the zygomatic-occipital distance. In adult males, the volume correlated with body height and weight. It appears that volume changes with age might be related to skeletal size and physique.

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Micro-air-vehicles (MAVs) and micro-flight robots that mimic the flight mechanisms of insects have attracted significant attention in recent years. A number of MAVs and micro-flight robots that use various devices have been reported. However, these robots were not practical. One of the reasons for this is that the flying mechanism of insects has not yet been clarified sufficiently. In particular, the dynamic behavior of the vortex formed on the insect wing and its growth process have not been clarified. The purpose of the present study is to clarify the dynamic behavior and the detailed structure of the vortices of the flapping butterfly wing. The authors conducted a particle image velocimetry measurement around the flapping butterfly wing of Cynthia cardui and Idea leuconoe and investigated the vortex structure of the wing and its dynamic behavior. A vortex ring is formed over the butterfly wings when the wings flap downward to the bottom dead position. The vortex ring then passes over the butterfly completely and grows until reaching the wake at the bottom dead position. The vortex ring is formed over the wings regardless of the type of butterfly, although the scale of the vortex ring varies with the butterfly type.

In Japan, integrated steelworks have greatly lowered their energy use over the past few decades through investment in energy-efficient processes and facilities, maintaining the highest energy efficiency in the world. However, in view of energy security, the steelmaking industry is strongly required to develop new technologies for further energy saving. Waste heat recovery can be one of the key technologies to meet this requirement. To recover waste heat, particularly radiant heat from steel products which has not been used efficiently yet, thermoelectric generation (TEG) is one of the most effective technologies, being able to convert heat directly into electric power. JFE Steel Corporation (JFE) implemented a 10-kW-class grid-connected TEG system for JFE's continuous casting line with KELK Ltd. (KELK), and started verification tests to generate electric power using radiant heat from continuous casting slab at the end of fiscal year 2012. The TEG system has 56 TEG units, each containing 16 TEG modules. This paper describes the performance and durability of the TEG system, which has been investigated under various operating conditions at the continuous casting line.

Eighteen patients with maxillofacial infections, who had trismus and swelling of the masseteric region, were investigated by CT. Spread of infection was evaluated with particular reference to the fascial spaces. The masticator space was divided into four parts and the changes in each were assessed together with the surrounding fascial spaces. There were changes in the masseter muscle and infection had spread into the upper parts of the masticator space in more than half of the patients. There was a fall in the CT value in the affected muscles, whereas it was raised in the parotid gland and adipose tissue. The clinical importance of CT is shown to have a significant role in the diagnosis and follow-up of maxillofacial infections.