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An idea hatched in the days of horse‐drawn travel is now a front‐runner in the race to find a pollution‐free car engine.

The history of an early Scottish library, founded on the collection of Bishop Robert Leighton, is outlined. Its decline and the subsequent efforts to restore it are explained; the cataloguing of the stock, conservation of books and restoration of the building are discussed and the work of the Appeal Fund described.

The purpose of the analysis is to estimate price elasticities of demand for individual FTSE‐100 stocks between 1 August 1994 and 31 July 1995.

This paper measures excess demand in order to measure the slope of the demand curve for individual stocks. An econometric approach is adopted that models the slope of the excess demand curve within an econometric framework using signed market maker transactions data between 1 August 1994 and 31 July 1995.

The findings confirm that the demand curves for individual stocks do slope downwards. For example, the mean estimated percentage fall in stock price caused by a new share issue that is 1 per cent of the existing number of outstanding shares is −5.6.

Downward sloping demand curves pose difficulties for theories in finance that rely on the law of one price and price‐takers in competitive markets. For example, the dividend policy and capital structure irrelevance theorems of corporate finance, and the efficient markets hypothesis assumption that the price of a stock is determined only by information about future cash flows and the discount rate are not consistent with a downward sloping demand curve.

The slope of the demand curve is estimated using an econometric model and market makers' transactions data for specific stocks. This approach identifies observable unexpected shifts in the demand for a stock as unexpected changes in market makers' inventories. This approach is superior to event studies because it provides multiple observations that enable the slope of the demand curve to be quantified with sufficient confidence to calculate the price elasticity of demand for the stock.

The delivery of assistance to SMEs, provided by enterprise councils at the local level, can vary between those bodies which are innovative and those which are pedestrian in their approach. Although it is generally accepted that most small firms in the UK sell to local markets, SMEs based within the Aberdeen area of Scotland play an important role in exporting and employment. The potential for birth and growth of firms exists in a number of targeted key sectors which aid the economic development of the Aberdeen area. However, assistance is required to bring people together in order to encourage networking, and this paper seeks to explore the process of facilitating an enterprise culture by examining the collaboration and partnership roles played by a LEC and a university in initiatives which foster enterprise. The relationship of the researchers and practitioners is similar to the model outlined by Oakey and Mukhtar where research and practice are used to inform each other, over time, to identify policy needs. The initiatives examined in this paper are the Entrepreneurs’ Club where established entrepreneurs mix with others at the new venture stage, and the Chrysalis Elite programme which links graduates with existing owner managers, creating a work‐based project involving groups of students. These links extend to the wider business community and organisations, including local entrepreneurs (who provide prizes and guidance), 3i and the Local Investors Network Company (LINC), who offer advice and opportunities. The main outcomes for policy in this paper are that collaboration between a LEC and a university can be very effective in assisting individuals or groups to meet the challenge of building entrepreneurial networks and that effective support can be provided for students to gain experience from the business community.

The purpose of this paper is to analyse structure and measure hardness of Co-Cr dental alloy samples made with two different technologies, conventional casting method (CCM samples) and additive direct metal laser sintering technology (DMLS samples), and to compare the results.

CCM samples were made in a conventional casting machine, using remanium 800+ Co-Cr dental alloy (Dentaurum, Ispringen, Germany). DMLS samples were fabricated out of EOS CC SP2 Co-Cr alloy (EOS, GmbH, Munich, Germany) using DMLS technology. Samples for structural analysis were plate-shaped (10 × 10 × 1.5 mm3) and for the hardness test were prismatic-shaped (55 × 10.2 × 11.2 mm3). Structure was analysed via an inverting microscope and colour metallography method.

CCM samples have a dense, irregular dendritic mesh, which is typical for the metallic phase of the Co-Cr dental alloy. DMLS alloy has a more homogenous and more compact structure, compared to CCM. Metals, the alloy basis consists of, form semilunar stratified layers, which are characteristic for the additive manufacturing (AM) technique. Hardness values of DMLS (mean value was 439.84 HV10) were found to be higher than those of CCM (mean value was 373.76 HV10).

There are several reports about possible use of AM technologies for manufacturing dental devices, and investigation of mechanical properties and biocompatibility behaviour of AM-produced dental alloys. Microstructure of Co-Cr alloy made with DMLS technology has been introduced for the first time in the present paper.

The purpose of this research paper is to compare corrosion data obtained from additive-manufactured heat-treated (HRx) and non-heat-treated (NHRx) cobalt-chromium (Co–Cr) alloys. Heat treatments are indicated as necessary in complex intra-oral framework production by additive manufacturing to remove accumulated thermal stresses. However, heat treatments have been linked to corrosion in cast dental alloys. Currently, there are few publications on this subject for laser-sintered dental alloys required for academic review.

Five rectangular specimens (n = 5), each with a total surface area of 10.27 cm2, were fabricated for the two groups. Specimens were immersed in an artificial saliva solution suspended by a nylon thread for 42 days at 37°C. Readings for Co, Cr and molybdenum ions released into the solution were obtained using an atomic absorption spectrometer at 1-, 4-, 7-, 14-, 21-, 28-, 35- and 42-day intervals at a detection limit of one part per million. Test methods are in accordance with ISO 10271.

Results showed a higher ion release in the HRx sample, statistically significant at 99 per cent confidence level (p < 0.01). A two-way ANOVA test conducted showed that there was a main effect of day and a main effect of finish, and there was also a significant interaction between these factors.

The study concludes that, although ion release in both samples was within the safe level recommended by ISO for the three major alloying elements, heat treatment, indeed, contributed extensively to the reduced corrosion resistance in the laser-sintered Co–Cr alloy. Further biocompatibility tests are recommended.

Gives reports and surveys of selected current research and developments in systems and cybernetics. They include: Scientific research and warfare; Cybernetics and psychology; Combating computer rage; Communication systems; Cybernetics and automation; Management cybernetics – human resources development; Innovative systems.