Field demonstration of 565 Mbit/s DPSK coherent transmission systemover 176 km of installed fibre

Reports the results of a 565 Mbit/s coherent system field trial over 176 km of installed SM fibre. Fully automated endless polarisation control was employed using a novel method and error free operation was achieved with BER readings of better than 10^-13     

Texturized protein products

Texture is changed in oilseed protein fractions by mechanical and chemical means in specialized equipment. Processing conditions are closely controlled to ensure end product forms wanted. The arrangement of equipment used in the production of textured proteins is discussed as it relates to a commercial plant design. The nature of feed materials and details of processing conditions required to produce texture in soy protein are presented. Other forms of textured oilseed protein are discussed.     

Craniometaphyseal and craniodiaphyseal dysplasia, head and neck manifestations and management

Mechanical allodynia (MA) following hand injury is a well-documented clinical problem. The purpose of this pilot study was to examine the relationship between hand MA and the upper limb tension test (ULTT). The ULTT mechanically stresses the neural structures from the C5/6/7 neural foramina to the median nerve distally. This study examined 29 subjects with unilateral hand MA before and after a 2-week neural self-mobilization programme. There was a significant difference between the subjects' affected and unaffected sides when tested using the ULTT, both in reproduction of symptoms and in reduced range of motion of the ULTT. Following the self-mobilization program, there was an improvement in the range of the ULTT, and subjects reported a reduction in their symptoms. Complete recovery was not obtained in all cases. The results of this study suggest that the ULTT is a useful tool both in assessment and treatment of subjects with hand MA.     

Optical receivers for lightwave communication systems

As long-wavelength optical telecommunications systems are now being installed in countries throughout the world, this is an opportune time to review the successful developments in detectors and receivers for this application. We given prominence to receivers using p-i-n and avalanche photodiodes, describing in some detail the principles of their operation as well as the details of their development. However, we also consider bipolar phototransistors, photoconductive detectors, and the receiver requirements for coherent optical systems, concluding with a broad comparison of the various receiver designs.     

A comparison of surfactants derived from alcohols based on petrochemical and oleochemical sources

Samples of lauryl-range alcohols derived from palm kernel oil, coconut oil and ethylene (Ziegler) were derivatized into alcohol sulfates and alcohol ether sulfates (2 moles of ethylene oxide adduct). Physical properties and performance characteristics for earch surfactant were evaluated both individually and in light-duty liquid (LDL) dish-washing formulations. The slight differences observed in the physical and performance properties of the surfactants and their formulations were assignable to slight differences the individual alcohol, alcohol sulfate and alcohol ether sulfate samples employed in this study. The magnitude and type of variation found in the samples resulted from normal production variation and not from any properties inherent to the nature of the alcohol source. We therefore conclude that alcohol sulfates, alcohol ether sulfates and LDLs formulated from them exhibit identical physical property and performance characteristics, regardless of whether the original alcohol was manufactured from petrochemical or eleochemical sources.     

Development of a spring loaded micro-pivot bearing

Ratchet and pawl mechanisms have been used for centuries in timing escapements and many other devices. As these devices are driven to ever-smaller dimensions, friction and other micro-forces become highly influential on device operation and reliability. This paper describes the design and assembly of a zero-friction, spring-loaded pivot bearing for possible replacement of the standard spring and rotational bearing in ratchet and pawl mechanisms. Three issues are discussed: development of a closed-form solution that relates bearing geometry and material properties to rotational spring rate, a macro-scale pivot bearing prototype to validate the closed-form solution, and the use of a micro-assembly workstation to assemble an ultra-miniature bearing comprised of micro-scale components.     

How to Physically Build and Maintain PoPs Around the World

A key contributor to Concert's success as a global IP network provider is its ability to install and maintain points of presence across the world. This paper describes the principles of physically building global networks and covers the practical details learnt by Concert.     

Neurogenic oedema and vasodilatation: effect of a selective neuronal NO inhibitor

The effects of a neuronal nitric oxide synthase (nNOS) inhibitor, 1-(2-trifluoromethylphenyl)imidazole (TRIM) on rat sensory saphenous nerve-induced neurogenic inflammation were investigated. TRIM (50 mg kg-1, i.p.), but not 2-trifluoromethylphenol (TRIMPOH) which lacks nNOS inhibitory activity, inhibited neurogenic oedema by 55.8 +/- 6.5% (n = 6, p < 0.05). The effect of TRIM was partially reversed by L-arginine (100 mg kg-1, i.v., p < 0.01). TRIM also caused a reduction (p < 0.05) in neurogenic vasodilatation but had no effect on neuropeptide responses induced by substance P + CGRP. Topically applied TRIM (100 microliters of 150-250 mg ml-1) inhibited neurogenic oedema (p < 0.01). Thus, use of this recently described nNOS inhibitor has provided new evidence to further the hypothesis that nNOS plays a role in modulating sensory nerve-mediated neurogenic inflammation.