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Musculoskeletal conditions are a major health concern in the USA because of a large aging population and increased occurrence of sport‐related injuries. Bone tissue engineering may offer a less painful alternative to traditional bone grafts with lower risk of infection. The purpose of this paper is to present a novel porogen‐based fabrication system for tissue engineering scaffolds using sucrose (C₁₂H₂₂O₁₁) as the porogen building material.

A new solid freeform fabrication system has been developed and tested, which uses pressurized extrusion to print highly biocompatible and water soluble sucrose bone scaffold porogens (or negtives). Polycaprolactone (PCL) scaffolds are manufactured by injecting molten polymer into the porogens, and the porogens are subsequently dissolved with water. The resultant scaffolds demonstrate the defined porous structure designed into the sucrose porogen manufacturing computer‐aided design model.

To optimize the porogen manufacturing process, the viscosity of sucrose mixtures is measured. Design of experiments is used to plan and analyze the relationships between the porogen characteristics and the process parameters. Reservoir pressure and print head speed are identified as the dominant factors affecting sucrose flow rate and porogen strut diameter, respectively. The biocompatibility of the new system is assessed by in vitro cell culture testing. Endothelial hybridoma cells (EAhy 926) and osteoblasts (7F2) seeded on the fabricated PCL scaffolds adhered to the scaffold and proliferated over four to six days. Epifluorescence and scanning electron microscopy images reveal cell spreading and multiple layers of cells on the scaffold surface. The results demonstrated the potential of the structured sucrose porogen‐based fabrication method in manufacturing bone tissue scaffolds.

This paper describes the first time use of biomaterials‐sucrose to make scaffold porogens and how an injection molded biopolymer scaffold can then be received.

Sages and seers in ancient India specified dharma, artha, kama and moksha as the four ends of a moral and productive life and emphasised the attainment of a proper balance between the spiritual health and the material health. However, most of their intellectual energy was directed towards the attainment of moksha, the salvation from birth‐death‐rebirth cycle. Kautilya, on the other hand considered poverty as a living death and concentrated on devising economic policies to achieve salvation from poverty but without compromising with ethical values unless survival of the state was threatened. Kautilya's Arthashastra is unique in emphasising the imperative of economic growth and welfare of all. According to him, if there is no dharma, there is no society. He believed that ethical values pave the way to heaven as well as to prosperity on the earth, that is, have an intrinsic value as well as an instrumental value. He referred the reader to the Vedas and Philosophy for learning moral theory, which sheds light on the distinction between good and bad and moral and immoral actions. He extended the conceptual framework to deal with conflict of interest situations arising from the emerging capitalism. He dedicated his work to Om (symbol of spirituality, God) and Brihaspati and Sukra (political thinkers) implying, perhaps, that his goal was to integrate ethics and economics. It is argued that the level of integration between economics and ethics is significantly higher in Kautilya's Arthashastra than that in Adam Smith's Wealth of Nations or for that matter in the writings of Plato and Aristotle.

Quality assured at Impalloy. A Bloxwich company has become the first UK supplier of cathodic protection products to be awarded BS5750 standard by Lloyds Register of Quality Assurance (LRQA) for its quality management systems.

Thyssen welding seeks new distributors and agents. Thyssen Welding, a product group within the Special Products Division of Thyssen Fine Steels Ltd is looking for distributors and agents.

Pyrene processes on display at Metals Engineering '86. Pyrene Chemical Services Ltd, a member of the Brent Chemicals International Group, will be displaying a selection of processes from its range of metal pre‐treatment chemicals on its stand at Metals Engineering '86 (1st–5th September) at the N.E.C., Birmingham.

Capital Trading presentation to GEC. Coated‐steel stockholder Capital Trading Ltd has, in conjunction with British Steel Corporation, recently made a presentation to companies within the GEC group on the benefits and applications of coated steels.

British Steel opt for Prodorite protection. More than £100,000 worth of orders has been secured by Wednesbury based Prodorite Ltd at British Steel Corporation plants in South Wales.

Speculations on the possibility of computers displaying intelligence are usually traced to Turing's 1950 paper, ‘Computing machinery and intelligence’. Claims for the literal intelligence of an appropriately programmed computer were publicly refuted by Searle in 1980. Optimism about the adequate simulation of intelligence is now further diminished. Analogies between the computer and the brain or mind have persisted. A contrasting perspective which links computers with documents through writing and through the faculty for constructing socially shared systems of signs has also been developed. From this perspective it can be shown that (i) claims for the literal intelligence of a computer rest on a similar basis to claims for the intelligence of a document, the production of depersonalised linguistic output, and (ii) that such claims are subject to an identical objection, that linguistic output is made available without a prior act of comprehension by the artefact. This paper places the Turing test in its intellectual and historical context. A claim that written words can give the appearance of intelligence, without the human capacity for dialectic response, is found in Plato's Phaedrus. This, too, must be placed in its historical context of a transition from predominantly oral to oral and written communication. Demonstrating that there are extensive similarities between the claims of computers and documents to literal intelligence is part of a progressive demystification of the computer.

In 1938 Barbara Wootton published Lament For Economics, an indictment of the state of contemporary economic theory. She complained that economics was of no use to anyone, and unintelligible to all except a small minority of specialists. Economists were unable to agree; they ignored reality, and often served as apologists for capitalism. Thus, economics was not a science, and could contribute little or nothing either to the understanding of capitalism or to the organisation of a future socialist society. Wootton’s criticism made no impact at the time, and she soon abandoned economics and became an eminent criminologist and social theorist. However, many of her arguments were repeated, 62 years later, in the French students’ manifesto that led to the formation of the Post Austistic Economics movement.

Business is increasingly coming under attack by pressure groups. Many managers, and particularly those in marketing functions, are having to respond to these challenges. Others are at least having to take cognisance of pressure groups. The nature of pressure groups, their role, the different types that may be found and how they operate are considered. Pressure group actions involving business are also discussed, but activity is emphasised. Managers are urged to seek an understanding of pressure groups, especially those groups likely to take an interest in their business.