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These principles of shoulder function have application in the treatment of instability and frozen shoulder syndrome, and provide an in vitro model to better understand static restraint function in the throwing mechanism.

In the present work, we have explored numerous ways of reducing the mean particle size of zeolite A, keeping the economic imperatives in mind. Efforts were directed toward reducing the crystallization time and having a narrower particle size distribution. In addition to the study of more conventional parameters, such as temperature, alkalinity, and water content, the effect of using microwaves, centrifuging, and ultrasonication was also explored. Highly localized temperatures of thousands of Kelvin and pressures of hundreds of atmospheres produced by ultrasonication were expected to disrupt the nucleation process in a manner that led to smaller crystals. Surprisingly, it was found that the application of ultrasonication did not lead to any decrease in particle size. The crystal morphologies obtained in the case of ultrasonication and stirring were completely different, which was rather unexpected. Subjecting the zeolite batch to short periods of microwave radiation led to a narrow particle size distribution with small crystal size. A direct correlation between the nominal SiO 2 /Al 2 O 3 ratio and the particle size was observed. Decreasing SiO 2 /Al 2 O 3 ratios led to a narrower particle size distribution. The yield dropped dramatically when the SiO 2 /Al 2 O 3 ratio dropped below 1. The use of some of these parameters has a synergistic effect and can be coupled to finally obtain a mean crystal size of about 0.5 µm within a very reasonable time frame of 5-6 h, which we believe can be easily tailored for the commercial synthesis of zeolite A. X-ray diffraction (XRD), laser scattering particle size analysis, scanning electron microscopy (SEM), EDAX, and energy-dispersive XRF have been used to characterize the zeolites synthesized.

We are delighted to offer a collection of papers that expose the reader to BT's thinking about network evolution, and some of its key service domains as we move to meet the demands of the 21st century. BT, like all other major telecommunications operators, is on the cusp of a major transformation. This has been true for a few years now and the industry has been positioning itself for the next wave of network-related investment. Within BT we are moving forward with growing confidence and we are working across the industry with suppliers and other operators to define the architectures and services that we want to support in the future.We hope you enjoy the contents and would encourage you to watch out for further editions of the Journal that will expand and develop the ideas presented here.