Showing papers by "University of Stirling published in 1970"

Evolution in closely adjacent plant populations VIII. Clinal patterns at a mine boundary

Abstract: SEVERAL previous papers in this series have been concerned with the evolution of differences between tolerant and non-tolerant populations of grasses growing over the boundaries of mine tip and pasture soils (Jam and Bradshaw, 1966, McNeilly and Antonovics, 1968, Antonovics, 1968a). Metal tolerant plants differ both physiologically and morphologically from normal plants in several features other than tolerance. Differences in calcium and phosphate response are recorded by Jowett (1959) and McNeilly (1966); Turner (1967) has shown differences in sulphur response; and Schwanitz and Hahn (1 954a, 1 954b) showed from a study of a range of plant species grown under standard conditions that in general tolerant plants had smaller flowers, smaller leaves and thinner stems. This was confirmed for Silene inflata by Broker (1963) who concluded from segregating progenies that dwarfness was not linked to tolerance and had probably been selected independently. Similarly, morphological differences have been recorded in the grass Agrostis tenuis on lead mines (Bradshaw, 1959; Jowett, 1964) and copper mines (McNeiIly, 1966). The morphological characters of plants of the grass Anthoxant hum odoratum L. taken from sites along a transect across a mine/pasture boundary were investigated with three main points in view.

Secondary Compositions and the Adams Spectral Sequence

Abstract: In each term of the Adams spectral sequence [1, 2] Massey products [10] can be formed and in the E2-term it has been found convenient to describe specific elements by means of these products. In Theorem (1.1) of this paper a description is given of the action of the differential d r on the Massey product in E r. In homotopy an analogous construction to the Massey product is the Toda bracket [15] and Theorem (1.2) discusses the convergence of Massey products in the Adams spectral sequence to Toda brackets in homotopy. It states that, under favorable conditions, a Massey product that is formed from permanent cycles will itself contain a permanent cycle that is realized in homotopy by an element of the appropriate Toda bracket. The statement of both Theorems (1.1) and (1.2) will be found in w 1 and the proofs are given in w167 5, 6. The intervening sections contain various geometric and algebraic preliminaries. A previous account of Theorem (1.2) was given in [12] and I am grateful to Professor J.F.Adams for suggesting the problem to which this theorem provides a partial solution. In 1966, Ivanovskil announced, at the Moscow congress, various results concerning the Adams spectral sequence and there appears to be some overlap between these results and Theorem (1.2). More recently, in Chicago, Lawrence has developed an account of the higher Massey product behaviour in the Adams spectral sequence and his results generalize the main theorems of this paper.

Salinity Preference in Corophium Volutator

Abstract: It has been suggested (McLusky, 1968 a) that migrations of Corophium volutator (Pallas) may occur in response to salinity. This suggestion was based on distributional evidence from the estuary of the River Ythan, Aberdeenshire, and assumed that the animals are able to detect salinity and exhibit a behavioural response to it. The presence and nature of such a response has been investigated by means of choice experiments. Burrowing, swimming and feeding behaviour of C. volutator have been studied by Meadows & Reid (1966) and Morgan (1965).

Kinetic hydrogen isotope effects in the ionization of some carbon acids

Abstract: Rate constants in aqueous solutions are reported for proton and deuteron abstraction by a variety of bases from tricarbomethoxymethane, the propan-2-one-1-sulphonate ion, 2-acetylcyclohexanone and ethyl nitroacetate. The rates of ionization were measured by using bromine or iodine as scavengers to remove the anions, and, for ethyl nitroacetate by direct observation of the rate of appearance of the anion. The kinetic isotope effects vary from k H / k D = 2.5 to k H / k D = 10.3, and confirm the regularities previously found (Bell & Crooks 1965; Bell & Goodall 1966). In particular, the results for the reaction of ethyl nitro-acetate with nine bases show clearly that with increasing basic strength the isotope effect passes through a well-marked maximum. Sterically hindered pyridine bases give rise to abnormally high isotope effects, probably attributable to increased tunnel corrections.

Size-distance invariance in perceptual adaptation

Abstract: Objects viewed through a facemask under water appear larger and closer than when viewed in air. Divers’ adaptation to this distortion was measured by obtaining estimates of the size and distance of an array of targets before and after a 20-min underwater dive. A negative correlation between size- and distance-adaptation scores indicated that most divers adapted to one dimension by counteradapting to the other. For example, some Ss adapted to size by increasing the distortion of apparent distance and some the other way around. The results were discussed in relation to the size-distance invariance hypothesis.

Light compensation points and photorespiration.

Abstract: SOME results of an investigation into light compensation points of photosynthesizing leaves are relevant to arguments about the occurrence or absence of photorespiration in illuminated leaves of species which do not release carbon dioxide into carbon dioxide-free air, and which have a carbon dioxide compensation point (Γ) close to zero1–3.

Bases and α -dimensions of countable vector spaces with recursive operations

Abstract: This paper is based on the notions originally described by Dekker [2], [3], and the reader is referred to these for explanation of notation etc. Briefly, we are concerned with a countably infinite dimensional countable vector space Ū with recursive operations, regarded as being coded as a set of natural numbers. Necessarily, then, Ū must be a vector space over a field which itself is in some sense recursively enumerable and has recursive operations.

Method and apparatus for erecting modular high-rise building

Abstract: A method and apparatus for erecting a high-rise building comprising a plurality of stacked modules. A wheeled delivery platform transports each module from a truck or the like on rails which extend parallel to a wall of the building and at right angles to the ultimate direction of module insertion in the building. The module is supported on a plurality of wheeled dollies each supported on rails carried by the platform, and these rails extend across the platform at right angles to the direction of movement of the platform. The platform, when properly positioned, has its rails aligned with corresponding rails carried by supporting means in the building structure so that the module can be rolled on said dollies off the delivery platform and into its predetermined position in the building. Alternate vertical columns of modules are provided with jacking means to permit the raising of the entire building by the height of one module plus suitable clearance space to permit the insertion of additional modules which will then comprise the next-lower floor of the building. Auxiliary jacking means provides for the raising of each module once it has been placed in its desired position by the amount of the predetermined clearance space to permit it to be secured to the module above it in the stack, and wedges maintain each such module in the elevated position after the auxiliary jacks are removed, thereby eliminating the necessity of at any time lowering the building structure to take up the clearance space.

Method of erection of high-rise building structure formed of modular units

Abstract: A method of erection of a high-rise building structure formed of modular units. A row of building support structures is positioned on the foundation, preferably below grade level, one such supporting structure being provided for each modular unit. Alternate ones of the supporting structures are permanently fixed in place, but the remaining supporting structures have associated therewith a jacking means capable of raising a modular unit supported thereon by an amount at least equal to the height of such modular unit. In assembling the building, a plurality of modules is placed on the supporting structures and secured together, after which the interconnected modules are raised by the jacking means. After having been raised by an amount substantially equal to the height of a modular unit, an additional module is placed in each open space, i.e., on each of the alternately spaced supporting structures not having an associated jacking means. Thereafter, each jacking means can be lowered, with the row of interconnected modules now supported on the supporting structures not having the associated jacking means through the intervening alternately spaced modules. Additional modular units can then be placed in the alternate spaces now provided atop each structural support having the jacking means. The lowest level of modular units are now all interconnected and the above-described operation can be repeated for each additional story in the building.

Student experiences of a problem-based learning nursing curriculum

Abstract: Describes the process of Problem-based learning (PBL) as it is used within the nursing programmes delivered by the School of Nursing and Midwifery, University of Dundee, Scotland and outlines the experience of the curriculum from students’ perspective. An outline of the particular approach adopted by the School and some of the issues associated with the integration and integrity of subjects across the curriculum is presented. The study is based upon a questionnaire given to all students undertaking the programme with a response rate of 74% (n=145). This is followed by interviews with a randomly sampled group of 5% (N=8). Evidence from these interviews is presented to highlight some of the strengths and weaknesses of this approach and to highlight some areas that require further research. The various curricula, which were developed in Scotland in response to Project 2000, highlighted the importance of producing nurses who were critical thinkers and able to engage in self-directed learning. The notion that students would develop to be reflective practitioners with skills for lifelong learning was also expressed as a fundamental principle underpinning the delivery of these programmes. The programmes that were developed tended to be subject orientated as opposed to demonstrating integration of themes.

On regular semigroups whose idempotents form a semigroup: Addenda

Abstract: The results in the first parts of Theorems 2 and 3 of the paper in the title (see [2]) have been previously obtained by B.M. Schein in Theorem 1.12, page 299 [4], and in Proposition 1.13 (combined with the last paragraph of page 300) [4], respectively. To deduce the first part of Theorem 2 [2] from Theorem 1.12 [4] one merely uses the fact that a binary relation R on a set X satisfies RR−1R ⊆ R if if and only if it satisfies: R{x) ∩ R(y) ≠ □ implies R(x) = R(y), for any x, y ∈ X (see Proposition 9, page 132 [3]).

Means for raising building of modular construction

Abstract: Apparatus for raising a building formed of a plurality of modular units. Each module raising unit comprises a rigid, stationary framework supporting a plurality of movable trusses which are raised and lowered relative to the stationary framework by means of a plurality of jacks. The jacks act on the upper portions of the movable trusses, and a principal function of the stationary framework is to provide support for the movable trusses to guard against side forces resulting from wind thrust imposed upon the building during its erection. Preferably, a plurality of hydraulic jacks is employed, but an auxiliary system of mechanical, screw-type jacks is also provided together with an associated followup system to provide support in the event of any failure in the hydraulic system. A supporting structure which includes a plurality of rails is also provided and may be mechanically coupled to each module raising apparatus. Each module may then be equipped with a plurality of flanged wheels which are adapted to ride on the aforementioned rails so that each module may be placed on the supporting structure with the wheels thereof resting upon the rails and with the module then being rolled into place upon the jacking apparatus.