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The Function of Scapular Muscle

In shoulder rehabilitation, it is important to evaluate scapular stability. However, it is not revealed how the mechanism runs for scapular stability. Additionally, the contribution of scapular muscles for scapular stability remains a matter of debate. Wherefore, I suggest some studies in this section to understand the function of scapulothoracic joint and the mechanism of scapular stability in detail. In the results of these studies, it was revealed that each scapular muscle activation is different for shoulder isometric contraction, and the exercise for a scapular muscle increases only the shoulder muscle strength of specific movement direction. If we can consider each scapular muscle individually by utilizing these results, we can provide more effective rehabilitation program

Nanolevel Surface Processing of Fine Particles by Waterjet Cavitation and Multifunction Cavitation to Improve the Photocatalytic Properties of Titanium Oxide

Titanium oxide particles were treated by water jet cavitation (WJC) generated and multifunction cavitation (MFC) using an ejector nozzle. Generation, growth, and collapse of cavitation are repeated with the particles of titanium oxide and platinum. Because the cavitation has an extremely high collapse pressure, the surface of the titanium oxide particles is processed by the microjets of cavitation in a reactor comprising the ejector nozzle. In the multifunction cavitation, ultrasonic irradiation of a waterjet during floating cavitation was used to generate microjets with hot spots. Hot working can be performed at the nanoscale on a material surface using this MFC process, resulting in morphological changes and variations in the surface electrochemical characteristics. The fundamental characteristics of multifunction cavitation were investigated theoretically and experimentally. Furthermore, the additional nozzle was put on the ejector nozzle in order to increase the temperature and pressure of bubble and the mechanism was clarified. The quantities of hydrogen and oxygen generated from titanium dioxide particles treated by multifunction cavitation in response to UV and visible light irradiation were remarkably increased compared to the amounts produced by particles treated by WJC processing. In this chapter, the methods and their results of processing particles by cavitation are introduced

Zipf Law in Firms Bankruptcy

Using an exhaustive list of Japanese bankruptcy in 1997, we discover a Zipf law for the distribution of total liabilities of bankrupted firms in high debt range. The life-time of these bankrupted firms has exponential distribution in correlation with entry rate of new firms. We also show that the debt and size are highly correlated, so the Zipf law holds consistently with that for size distribution. In attempt to understand ``physics'' of bankruptcy, we show that a model of debtor-creditor dynamics of firms and a bank, recently proposed by economists, can reproduce these phenomenological findings