Showing papers by "University of Stirling published in 1971"

The urban mosaic : towards a theory of residential differentiation

Abstract: Preface 1. The city as a mosaic of social worlds 2. Ecological structure and factor structure 3. The bases of residential differentiation 4. Residential differentiation and social change 5. The spatial patterning of residential differentiation Summary and conclusion Bibliography Index.

Some Effects of Salinity on the Mysid Praunus Flexuosus

Abstract: The population dynamics of the mysid crustacean Praunus flexuosus have been studied at Ardmaddy Bay, Loch Etive. A salinity tolerance range of 2–33‰ has been demonstrated, over which the body tissues experience the range 11–28‰. Comparison is made between the osmoregulatory capacity of Praunus flexuosus and the closely related Neomysis integer.

The degree of mimetic protection gained by new partial mimics

Abstract: THE study of Batesian Mimicry has contributed considerably to our understanding of natural selection and the nature of the predator-prey relationship. Since the theory of Batesian Mimicry was proposed (Bates, 1862) numerous workers have inferred its existence from the presence of palatable species resembling distasteful and usually conspicuous species with which they occur. There have also been numerous experimental studies on mimicry, but because of the difficulty of observing this phenomenon in nature they have usually been carried out under unnatural conditions (Muhlmann, 1934; Brower, 1958a, b, c, 1960; Schmidt, 1958, 1960; Brower et al., 1960; Sexton, 1960; Brower and Brower, 1962; Reiskind, 1965; Brower et al., 1967; Cook et al., 1969; Morrell and Turner, 1970). Nearly all these experiments have successfully demonstrated the efficacy of the mimetic pattern in protecting the mimic. However, far fewer experiments have investigated the processes that have led to the evolution of a near perfect resemblance between the mimic and the model. The evolution of the mimetic pattern from the originally nonmimetic form is best explained by the occurrence of a single mutation, giving some resemblance to the model, followed by the selection and fixation of modifying genes gradually perfecting the resemblance (Sheppard, 1959; Clarke and Sheppard, l960a, b). The experiments of Schmidt, Sexton and Muhlmann (bc. cit.) in the laboratory all show that more protection is obtained by better mimics, though significant protection may also be received by poorer mimics. Studies of this type on wild predators have been few. Morrell and Turner using artificial prey and wild birds also show that poorer mimics, though less frequently eaten than non-mimetic prey, are more frequently eaten than better mimics. Brower et al. (1967) and Cook et al. (1969) found that there is sometimes underpredation of artificial mimics (painted moths) compared with non-mimetic moths. The experiments described in this paper were aimed to study further the action of mimicry using uncaged predators with artificial prey and to investigate the effectiveness of mimics showing incomplete resemblance to the model.

Reaction Orders and Isotope Effects in the Reversible Addition of Water to 1,3-Dichloroacetone in Aqueous Dioxan

Abstract: (hydrogen chloride, perchloric acid, four carboxylic acids and 2,6-dichlorophenol). Reaction orders with respect to water were determined, and also kinetic isotope effects in systems containing 50 and 100 atom % of deuterium. It is concluded that the uncatalysed reaction involves a cyclic transition state containing two extra water molecules, one of which may be replaced by a molecule of catalyst. The dependence of the kinetic orders and isotope effects upon the nature of the catalyst is attributed mainly to differences in the hydration or other properties of the catalyst in the initial state. It is believed that proton movement is partly synchronous with the making or breaking of the carbon-oxygen bonds, but there is no evidence that more than one proton moves simultaneously. The equilibria and kinetics of the reversible addition of water to carbonyl compounds, R1R2CO + H20 ? R1R2C(OH)2, have been studied by a number of workers (for a summary see Bell I966). Recent work (Bell, Millington & Pink I968: subsequently referred to as B.M.P.) on the hydration of 1,3-dichloroacetone in dioxan and acetonitrile solution showed that the kinetic orders with respect to water were consistent with a cyclic transition state containing water molecules in excess of the one which reacts, as originally suggested by Eigen ( 965). Similar conclusions were reached by Dahn & Aubort (I968) for the hydration of halo-p-benzoquinones in aqueous tetrahydrofuran, and by Haldna, Erriline & Kuura (I968), who investigated the dependence of the rate of hydration of monochloroacetone on the water activity in aqueous sulphuric acid. The purpose of the present study was to obtain more evidence about the structure of the transition state by investigating reaction orders in the presence of a variety of catalysts and by measuring hydrogen isotope effects. EXPERIMENTAL It is essential that the dioxan employed should be completely free from acetal, which in the presence of water and acid catalysts is hydrolysed to acetaldehyde thus causing u.v. absorption in the region used for kinetic measurements. Both g.l.c. analysis and measurement of u.v. absorption at 285 nm after treatment with an equal volume of 2 moll-1 hydrochloric acid showed that AnalaR dioxan contained about 0.5 % of acetal. Our measurements were carried out with solvent

A Comparative Study of Preferential Adsorption in Bromoform (1), Benzene (2), and Polymer (3) Systems by Light Scattering and Density Gradient Ultracentrifugation

Abstract: Preferential adsorption in bromoform (1), benzene (2), and polymer (3) systems has been studied by two different methods: sedimentation equilibrium in a density gradient and light scattering. The preferential adsorption parameters were estimated for mixtures containing polystyrene and poly(α-methylstyrene) as the polymer component. In both systems, inverse adsorption was observed, in which the poor solvent bromoform is selectively adsorbed by the polymer. This occurred at low bromoform concentrations in the mixture but as the amount of bromoform increased there was a reversion to preferential adsorption of the benzene. An attempt to analyse the data in terms of the thermodynamic interactions indicated that agreement between theory and experimental data could only be obtained if it was assumed that inclusion of a ternary interaction parameter was necessary in the theoretical treatment.

Mechanical handling of goods

Abstract: This invention provides an apparatus for the mechanical handling of goods in which the goods are stacked upon a flat flexible pallet, in the form of an envelope with a mouth at one end, which takes up very little space and which will not support the goods when the goods are to be moved. To lift the goods the pallet is partially inflated through the mouth by blowing air into the envelope and a rigid supporting member is introduced into the envelope through the mouth so that the goods can be lifted, moved and put down again whereupon the supporting member can be removed and the air supply turned off so that the pallet lies flat again.

The Urban Mosaic: The city as a mosaic of social worlds

Abstract: RESIDENTIAL DIFFERENTIATION The urban community is neither an undifferentiated mass nor a haphazard collection of buildings and people. In the residential differentiation of the city the urban fabric comes to resemble a ‘mosaic of social worlds’. Similar populations cluster together and come to characterize their areas. As Park put it: In the course of time every sector and quarter of the city takes on something of the character and qualities of its inhabitants. Each separate part of the city is inevitably stained with the peculiar sentiments of its population. The effect of this is to convert what was at first a mere geographical expression into a neighbourhood, that is to say, a locality with sentiments, traditions, and a history of its own. The residential differentiation of the urban population takes place in terms of many attributes and in many ways. Almost any criterion which can be used for differentiating between individuals and groups may become the basis for their physical separation. The process of separation may be accomplished through force, through a variety of sanctions, through a voluntary aggregation designed as a defence against unfamiliar ideas or customs or as an escape from persecution and discrimination, and through a selection of market forces. In much early town planning residential differentiation and segregation appear as prime characteristics.

Guild Socialism and the Labour Research Department

Abstract: The title of this chapter describes its purpose: it is to chronicle, and to some extent to evaluate, two diminutive movements which during part of the first quarter of the present century exercised an influence out of all proportion to the number of their direct adherents. The amount of this influence may seem the more surprising because there was so much duplication in membership. The staff, paid and unpaid, of the Labour Research Department, at least until 1921, were Guild Socialists almost to a man, as were most of the general secretaries of the trade unions, trades and labour councils, and trade-union branches which sustained the L.R.D. with modest affiliation fees. Not all of them, by any means, were enrolled in the tiny paid-up membership (never reaching a thousand) of the National Guilds League; but it was assumed that any N.G.L. member would support the work of the L.R.D., and if he or she lived in London, would join actively in it. For some years, in fact, the two movements were in effect two sides of the same coin — that coin which the war correspondent Henry Nevinson, using a different metaphor, characterised once and for all as The Stage Army of the Good — the Guild movement providing the theory and the propaganda, while the L.R.D. worked at getting out the facts which were to be the sinews of the propagandists’ war.