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THE chemist regards magnesium as a highly reactive metal for such reasons as the inflammability of its powder or foil in air, its active displacement of hydrogen gas from many aqueous chloride solutions, and its position near the reactive end of the electrode‐potential series. All these suggest that the metal would be unsuitable for constructional engineering. Yet engineers use alloys, rich in magnesium, up to 98 per cent of the metal, for an increasing number of services, although the alloying elements do not, as a rule, greatly cut down, and may even increase, the corrosion rate. Their industrial use is possible because the liability to corrode, reckoned over a reasonably prolonged period, is not a definite property of a metal such as conductivity, which is subject only to relatively small changes with alteration of environment, but is highly specific to metal‐liquid and metal‐gas systems. Moreover, these systems may undergo important changes with time owing to the intervention of films of corrosion products, and the rate of attack may be governed by the physical characteristics of these films, which will vary with the adjacent liquid and gases. Thus, in stagnant caustic alkalies magnesium may be reckoned as almost incorrodible because of the intervention of a film of hydroxide of the self‐healing type which, in these conditions, is highly impervious to magnesiumions; but in the presence of alkali chlorides the corrosion product is physically different and rapid corrosion occurs. Many dilute acids attack magnesium rapidly, but hydrofluoric acid scarcely at all, no doubt owing to the formation of a protective film of fluoride.

We study the spatial diffusion of stock backdating, an instance of corporate misconduct about which public information was virtually absent until 2005. Contrary to the findings of Bizjack, Lemmon, and Whitby (2009), our results reveal that this “invisible” practice did not diffuse through board interlocks. Rather, stock backdating spread through geographic proximity: firms were more likely to backdate stock options to the extent that other firms located geographically close to them had done so. Lending support to the importance of localized interactions among members of the local business elite, the effect of geographical proximity was conditional on high levels of local board interlocks. Our findings regarding the differential impact of geographic proximity and board interlocks on the diffusion of this invisible practice are analogous to the diffusion pattern of controversial practices proposed by Davis and Greve (1997).

The Department of Scientific and Industrial Research has been responsible for investigations on the corrosion of metals since 1924, when a Corrosion Research Committee was set up with the late Dr. G. D. Bengough as its first senior investigator. In 1927 research on atmospheric corrosion directed by Dr. W. H. J. Vernon was taken over by D.S.I.R. and in 1928 the Group was transferred from the Royal School of Mines in London to the then Chemical Research Laboratory at Teddington. This establishment had been inaugurated several years previously as a separate D.S.I.R. station situated in the same grounds as the National Physical Laboratory. Quite recently it has achieved the status of National Chemical Laboratory; but the ‘C.R.L.’ (now the ‘N.C.L.’) has always derived great benefit from its proximity to its much larger and older sister station.

The Swedish agricultural landscape has changed dramatically since 1945. Agricultural land has been abandoned and the general trend has been towards less scenic and biological variety. People express a relatively high willingness to pay for preservation of agricultural landscape in contingent valuation surveys and they tend to prefer high degrees of variability. Landscape is shown to be a multidimensional entity with a complex structure of economic characteristics. The complexity makes it unlikely that simple policy solutions are optimal. It is difficult to analyse policy options in this case but much speaks in favour of some differentiated area subsidy for a large fraction of the agricultural land and individual contracts for the most biologically valuable sites.

This chapter discusses the potential role of geographic information systems (GIS) for infection control within the hospital system. The chapter provides a brief overview of the role of GIS in public health and reviews current work applying these methods to the hospital setting. Finally, it outlines the potential opportunities and challenges for adapting GIS for use in the hospital setting for infection prevention. A targeted literature review is used to illustrate current use of GIS in the hospital setting. The discussion of complexity was compiled using the nonadoption, abandonment, scale-up, spread, and sustainability (NASSS) framework. Challenges and opportunities were then extracted from this exercise by the authors. There are multiple challenges to implementation of a Hospital GIS for infection prevention, mainly involving the domains of technology, organization, and adaptation. Use of a transdisciplinary approach can address many of these challenges. More research, specifically prospective, reproducible clinical trials, needs to be done to better assess the potential impact and effectiveness of a Hospital GIS in real-world settings. This chapter highlights a powerful but rarely used tool for infection prevention within the hospital. Given the importance of reducing hospital-acquired infection rates, it is vital to identify relevant methods from other fields that could be translated into the field of hospital epidemiology.

Corrosion has been defined as the destruction of metal by chemical or electrochemical reaction with its environment. Methods of corrosion control become more and more important as we are increasingly concerned about conserving our natural resources. For effective control of corrosion, we must have a thorough understanding of its nature and methods of measurements. Little correlation exist between laboratory tests and field performance. Atmospheric exposure tests are required to determine the relative aggressiveness of the environment to a variety of materials that might be selected for use. The development of data for this purpose makes possible a suitable selection of materials. Atmospheric small scale tests can often be made the basis of positive statement about the durability of metals, alloys, metal couples and painted metals on large structures and it needs very careful planning and preparation.

The long‐awaited regulations to provide statutory compositional requirements for the ever‐increasing range of meat products have at last arrived; presented in the form of a triology—The Canned Meat Product Regulations, The Meat Pie and Sausage Roll Regulations and The Sausage and Other Meat Product Regulations—all of which apply to England and Wales only; presumably the Scottish counterparts, modified for the geographical variations in commodities, will appear in due course. The Meat Pie and Sausage Roll Regulations come into operation on May 31 1968; the other two on May 31 1969.

The importance of corrosion from an industrial point of view is recognised, in principle at least, by layman and expert alike, but surgical aspects of the same problem, though not less important, have not always received comparable recognition. This is due to a number of causes, including the fact that it is frequently the less obvious cases of corrosion that cause the greatest annoyance to the surgeon.

Two major computerized systems, ECG and Clinical Chemistry, have been meshed on an 1BM‐1800/System/7 tandem combination. The System/7 computer serves as (1) an analog‐to‐digital device acquiring both ECG data from 3‐channel data acquisition carts over telephone lines, and laboratory data from autoanalyzers over direct cabling; and (2) a communications concentrator controlling a network of interactive video display units and printers in both the Clinical Chemistry and the ECG Laboratories via asynchronous and synchronous multiplexers. An operating system has been written for the System/7 which handles all I/O from external devices and communicates to the 1BM‐1800 over a direct memory access channel at the rate of 105 words per second. The meshing of the systems has a synergistic effect which makes the system extremely powerful at an economic price level.