Showing papers by "University of St Andrews published in 1986"
TL;DR: This article showed that chronic intraventricular infusion of D,L-AP5 causes a selective impairment of place learning, which is highly sensitive to hippocampal damage, without affecting visual discrimination learning.
Abstract: Recent work has shown that the hippocampus contains a class of receptors for the excitatory amino acid glutamate that are activated by N-methyl-D-aspartate (NMDA) and that exhibit a peculiar dependency on membrane voltage in becoming active only on depolarization. Blockade of these sites with the drug aminophosphonovaleric acid (AP5) does not detectably affect synaptic transmission in the hippocampus, but prevents the induction of hippocampal long-term potentiation (LTP) following brief high-frequency stimulation. We now report that chronic intraventricular infusion of D,L-AP5 causes a selective impairment of place learning, which is highly sensitive to hippocampal damage, without affecting visual discrimination learning, which is not. The L-isomer of AP5 did not produce behavioural effects. AP5 treatment also suppressed LTP in vivo. These results suggest that NMDA receptors are involved in spatial learning, and add support to the hypothesis that LTP is involved in some, but not all, forms of learning.
3,488 citations
TL;DR: In this paper, the notion of qualitative information and the practicalities of extracting it from experimental data were considered, based on ideas from the generalized theory of information known as singular system analysis due to Bertero, Pike and co-workers.
2,158 citations
01 Nov 1986-Quarterly Journal of Experimental Psychology Section B-comparative and Physiological Psychology
TL;DR: It is concluded that hippocampal lesions severely but partially impair spatial but not visual reference memory and give rise to different patterns impairment in different working-mermory tasks.
Abstract: This paper reports a series of three experiments that tested the “spatial-mapping” and “working-memory” theories of hippocampal function. The experimental designs incorporate separate reference- an...
304 citations
TL;DR: In this article, the Navier-Stokes equations are solved with exact solutions for two-and three-dimensional shear flows of unbounded extent, including two-dimensional stagnation point flows and 2-dimensional flows with uniform vorticity.
Abstract: New classes of exact solutions of the incompressible Navier-Stokes equations are presented. The method of solution has its origins in that first used by Kelvin (Phil. Mag. 24 (5), 188-196 (1887)) to solve the linearized equations governing small disturbances in unbounded plane Couette flow. The new solutions found describe arbitrarily large, spatially periodic disturbances within certain two- and three-dimensional 'basic' shear flows of unbounded extent. The admissible classes of basic flow possess spatially uniform strain rates; they include two- and three-dimensional stagnation point flows and two-dimensional flows with uniform vorticity. The disturbances, though spatially periodic, have time-dependent wavenumber and velocity components. It is found that solutions for the disturbance do not always decay to zero; but in some instances grow continuously in spite of viscous dissipation. This behaviour is explained in terms of vorticity dynamics.
280 citations
TL;DR: In this article, the authors applied the NORMIX multivariate clustering algorithm to 168 basins in Scotland and five regions were identified, corresponding to physically reasonable basin types and all but one of which yield homogeneous distributions of flood frequency.
223 citations
TL;DR: In this paper, the photon correlation and other vital performance characteristics of silicon avalanche photodiodes operated in photon counting or the Geiger mode were examined, and their suitability as detectors for photon correlation spectroscopy and laser velocimetry measurements was assessed.
Abstract: We examine the photon correlation and other vital performance characteristics of silicon avalanche photodiodes operated in photon counting or the Geiger mode, and assess their suitability as detectors for photon correlation spectroscopy and laser velocimetry measurements.
198 citations
TL;DR: An algorithm for obtaining the strict consensus supertree of two consistent sample trees is presented, as are procedures for merging two inconsistent sample trees.
Abstract: Given two dendrograms (rooted tree diagrams) which have some but not all of their base points in common, a supertree is a dendrogram from which each of the original trees can be regarded as samples The distinction is made between inconsistent and consistent sample trees, defined by whether or not the samples provide contradictory information about the supertree An algorithm for obtaining the strict consensus supertree of two consistent sample trees is presented, as are procedures for merging two inconsistent sample trees Some suggestions for future work are made
183 citations
163 citations
TL;DR: In this paper, the conductances of LiClO 4 and LiCF 3 SO 3 solutions in a low mol. wt polyether have been measured as a function of salt concentration.
150 citations
TL;DR: In this paper, the authors link together kings, war, and the economy of Hellenistic kings and argue that the economy was dependent purely on the fruits of military success and not on social and economic success.
Abstract: My title links together kings, war, and the economy, and the linkage is deliberate I do not of course wish to suggest that Hellenistic kings did nothing but fight wars, that they were responsible for all the wars in the period, that royal wars were nothing but a form of economic activity, or that the economy of the kings was dependent purely on the fruits of military success, though there would be an element of truth in all these propositions But I wish to react against the frequent tendency to separate topics that are related, the tendency to treat notions relating to what kings were or should be as something distinct from what they actually did, and the tendency to treat political and military history on the one hand as something separate from economic and social history on the otherA number of provisos should be made at the outset The title promises more than the paper can deliver; in particular, more will be said about kings and war than about kings and the economy The subject is handled at a probably excessive level of generalization and abstraction I talk about Hellenistic kings in general, but in practice it would obviously be necessary to draw distinctions between different dynasties, different times and places, and individual rulers, and some of those distinctions I shall indicate Conclusions are provisional and subject to modification and considerable expansion in detail Finally, two points of terminology I use the word ‘Hellenistic’ for no better reason than out of the force of acquired habit, but of course the word and the concept are modern inventions that were unknown to the ancient world
143 citations
TL;DR: Three experiments that adopt an interference technique to investigate the involvement of movement in the production of a spatial code confirm the interference effects of incompatible movement on the generation of the spatial code and show that movement per se rather than attention to the movement can cause a performance decrement.
Abstract: Three experiments that adopt an interference technique to investigate the involvement of movement in the production of a spatial code are described. Arm movements rather than the more commonly empl...
TL;DR: Songbirds learn the songs that they sing from other individuals, but the learning is not always accurate, which leads to dialects and to changes with time in the songs found in one place.
Abstract: Songbirds learn the songs that they sing from other individuals, but the learning is not always accurate. This leads to dialects and to changes with time in the songs found in one place. Are these phenomena functional or are they simply byproducts of vocal learning which has evolved for quite different reasons?
TL;DR: In this paper, the authors examined some of the mechanisms contributing to aggregation behavior by experimentally manipulating sea urchins, purported predators and food during autumn 1983 and spring 1984 both in the laboratory and field.
Abstract: Defensive aggregation by Strongylocentrotus droebachiensis has been invoked as the fulcrum for the transformation of macroalgal beds into coralline barrens in the northwest Atlantic. We critically examined some of the mechanisms contributing to aggregation behavior by experimentally manipulating sea urchins, purported predators and food during autumn 1983 and spring 1984 both in the laboratory and field. We utilized several approaches to examine a range of sea urchin responses to the presence of food, tethered predators, caged predators, crushed con-specifics in the field and predators in laboratory tanks. Some of the field cages had the property of allowing free passage to sea urchins while retaining lobsters; this allowed distinctions to be made between artifacts caused by cage walls or topographic barriers and unrestricted behavioral responses of sea urchins. The results falsified the hypothesis that aggregations of S. droebachiensis are elicited by predators. Except in the presence of algae, sea urchins always avoided decapod predators (but not sea stars) and fled from the vicinity of injured conspecifics. However, avoidance behavior was subordinate to feeding responses, demonstrated by mass migrations of sea urchins into cages (with lobsters) to feed on algae. We reaffirmed by observation and manipulation previous studies which showed that sea urchins aggregate only in the presence of food. Two types of sea urchin groupings were delineated: (1) surficial two dimensional associations, often caused by topographic or other features which inhibited dispersal and (2) cohesive three-dimensional aggregations induced by food.
TL;DR: Among 48 U.K. companies surveyed in this article, those with more vulnerable core technologies employ more specialist planners, more forecasting and evaluative techniques, in proposal generation and evaluation, irrespective of size.
Abstract: Among 48 U.K. companies those with more vulnerable core technologies employ more specialist planners, more forecasting and evaluative techniques, in proposal generation and evaluation, irrespective of size. Allowing for size, hostility of market conditions is associated with greater scope, status and involvement of planners, and diversification and divisionalization with formality and scope of planning.
TL;DR: The results are consistent with the increase in amino acid gluconeogenesis as a result of cortisol administration implied in previous studies, but failed to show a definitive cortisol effect on this pathway in the eel liver.
Abstract: Plasma and liver composition, liver enzyme activities, and metabolite flux in isolated hepatocytes have been studied in immature American eels,Anguilla rostrata, injected daily IP with saline or cortisol (035 mg/kg eel) Plasma cortisol values were significantly increased above saline controls in those eels receiving cortisol at 3h and 6h following the final (tenth) injection On day 6 and 10 of injection plasma cortisol levels were significantly below saline controls 24h following cortisol injection Plasma glucose values were significantly depressed in the cortisol-injected eels at both 6 and 24h following the final (tenth) injection At the 24h sampling time, plasma protein had significantly increased, but there was no change in either plasma amino acid or fatty acid levels An increased hepatosomatic index was attributed to a major increase in total lipids, as both protein and glycogen contents were decreased Of the liver enzymes assayed, significant activity changes occurred only for lactate dehydrogenase (decreased), mitochondrial citrate synthase (increased) and phosphoenolpyruvate carboxykinase (increased) 24h following the final (tenth) cortisol injection Although enzyme activity changes implied increased liver gluconeogenesis, the absolute rate of lactate, alanine, and aspartate incorporation into glucose declined in viable hepatocytes isolated from cortisol-injected eels compared to the saline controls Relative changes in metabolite flux did support a preferential increase in gluconeogenesis from amino acids These results are consistent with the increase in amino acid gluconeogenesis as a result of cortisol administration implied in previous studies, but failed to show a definitive cortisol effect on this pathway in the eel liver It is suggested that other hormones (eg thyroxine, catecholamines, glucagon) may interact in a complex way with cortisolin vivo to bring about the biochemical changes observed in this study The rapid clearance of exogenously injected cortisol noted in this study makes causal relationships between the injected hormone and any observed metabolic effect in the intact animal difficult
TL;DR: High-energy phosphate stores in the liver were greatly depleted, although there was no measurable decline in liver glycogen content and Glycolytic activation in the white muscle is argued to have a major impact on the hypoxia tolerance of trout.
Abstract: Rainbow trout were subjected to 1 and 3h of environmental hypoxia (20Torr, 4°C), after which samples of blood, heart, brain, liver, and red and white muscle were removed for metabolite determination. The heart, brain and white muscle all showed signs of glycolytic activation. High-energy phosphate stores in the liver were greatly depleted, although there was no measurable decline in liver glycogen content. Glycolytic activation in the white muscle is argued to have a major impact on the hypoxia tolerance of trout, as this tissue produces the bulk of the lactate. These responses of the trout are contrasted with those of the African lungfish, a fish which is relatively tolerant of hypoxia.
TL;DR: Nowhere is structure as a manifestation of dynamic processes so clearly demonstrated as in the cyclical formation of nucleoli as in this study of ribosomes in eukaryotic cells.
TL;DR: A review is provided of the various facets of each of the three main self-incompatibility systems, including a detailed summary of the current knowledge of the rejection mechanism, to demonstrate that the implicit assumption that these systems have a common S locus, and also evolutionary theories linking the systems, need to be treated with considerable caution.
Abstract: The view put forward by some authors that flowering plant self-incompatibility mechanisms of the homomorphic sporophytic and heteromorphic sporophytic types have a close evolutionary relationship, with one form being evolved from the other, or both forms directly evolved from ancestors with homomorphic gametophytic incompatibility, is challenged. A review is provided of the various facets of each of the three main self-incompatibility systems, including a detailed summary of our current knowledge of the rejection mechanism, to demonstrate that the implicit assumption that these systems have a common S locus, and also evolutionary theories linking the systems, need to be treated with considerable caution.
TL;DR: In this article, it was shown that if P(z) is a non-constant, real, even polynomial with positive leading coefficient, then every non-trivial solution of the equation f^{\prime\prime}+{e}^P{f} = 0 satisfies λ(f) = ∞.
Abstract: We consider the equation \(\rm f^{\prime\prime}+{A}(z){f}=0\) with linearly independent solutions f1,2, where A(z) is a transcendental entire function of finite order. Conditions are given on A(z) which ensure that max{λ(f1),λ(f2)} = ∞, where λ(g) denotes the exponent of convergence of the zeros of g. We show as a special case of a further result that if P(z) is a non-constant, real, even polynomial with positive leading coefficient then every non-trivial solution of \(\rm f^{\prime\prime}+{e}^P{f}=0\) satisfies λ(f) = ∞. Finally we consider the particular equation \(\rm f^{\prime\prime}+({e}^Z-K){f}=0\) where K is a constant, which is of interest in that, depending on K, either every solution has λ(f) = ∞ or there exist two independent solutions f1, f2 each with λ(fi) ≤ 1.
TL;DR: In this article, an analysis of the morphology of nine ramparts suggests that these may have formed at the foot of slowly thickening snowbeds, with rockfall debris accumulating against their distal slopes, and that snowbed melting at the end of the stadial was uninterrupted by prolonged periods of stability or renewed growth.
Abstract: Arcuate and linear protalus ramparts of inferred Loch Lomond Stadial age are widespread in upland Britain outside the limits of contemporaneous glaciers. Survey and analysis of the morphology of nine ramparts suggests that these may have formed at the foot of slowly thickening snowbeds, with rockfall debris accumulating against their distal slopes, and that snowbed melting at the end of the stadial was uninterrupted by prolonged periods of stability or renewed growth. Rampart sediments consist of poorly-sorted assemblages of clasts with a variable infill of fines. Clast size and shape are strongly influenced by lithology, but rampart clasts are characteristically more angular and ‘slabbier’ than those of similar lithology in ice-marginal moraines. Ramparts may also be distinguished from moraines by their location, morphology, lack of a true matrix of fines and absence of erratics, and from talus-foot rock glaciers in terms of their width and the absence of flow structures. The mapped distribution of rampart altitudes across the Scottish Highlands displays a marked regional trend, with the lowest features in the west and south and highest in the Cairngorms. This pattern mirrors that of reconstructed firn line altitudes of Loch Lomond Stadial glaciers, and is inferred to reflect a pronounced eastwards and northwards decline in snowfall during the stadial.
TL;DR: The major circulating antioxidant protein, caeruloplasmin (CP), was significantly increased by 25-30% in DMD patients compared with both adult and young male controls suggesting that increased LPX may be a trigger for CP synthesis.
TL;DR: In this paper, the authors classify landslide failures in Scotland into four categories: non-rotational rock slope failures (major rockfalls, translational slides, topples or sags, often in some combination), rotational slope failures; debris flows; and translational slide in drift or regolith.
Abstract: Almost all documented landslides in Scotland belong to one of four categories: non‐rotational rock slope failures (major rockfalls, translational slides, topples or sags, often in some combination); rotational rock slope failures; debris flows; and translational slides in drift or regolith. Non‐rotational rock slope failures are particularly common on Highland metamorphic rocks, especially schists, and on igneous scarps in the Hebrides and Midland Valley; rotational rock slope failures almost invariably occur in weak sedimentary rocks overlain by resistant igneous rocks; and debris flows are most common on sandy drift or regolith. Former glacial activity has also been of importance in determining landslide distribution. The great majority of rock slope failures are ancient features, but debris flows and small translational slides in drift (both triggered mainly by intensive rainstorms) are much more frequent at present and cause much greater damage, particularly to communications.
TL;DR: A detailed examination of the boundary between Peach and Home's (1899) Northern and Central Belts, in the Lower Palaeozoic rocks of the Southern Uplands of Scotland and their Irish continuation in Longford-Down, demonstrates it to be a major Caledonian sinistral wrench fault as discussed by the authors.
Abstract: A detailed examination of the boundary between Peach and Home's (1899) Northern and Central Belts, in the Lower Palaeozoic rocks of the Southern Uplands of Scotland and their Irish continuation in Longford–Down, demonstrates it to be a major Caledonian sinistral wrench fault. Maps and descriptions of outcrops of the fault at Slieve Glah in County Cavan, at Orlock Bridge on the NE coast of Down, at Cairngarroch on the Rhinns of Galloway and at Garvald, 11 km SW of Dunbar, are presented. A distinctive fault fabric, clearly the result of repeated sinistral slip at the first three localities, characterises these outcrops along the 400 km trace. The fabric elements include: (1) lenticular shearing of arenites in the fault protolith, (2) a fault-associated phyllonitic fabric, with abundant pressure-solution seams, overprinting the regional S1, (3) numerous foliation-parallel quartz segregations, (4) refolding of the regional S1 cleavage, segregation veins and the phyllonitic fabric in at least two generations of steeply plunging, sinistrally-verging folds, (5) a non-penetrative crenulation cleavage, (6) a locally developed sinistral S–C fabric, and (7) typical protomylonite, mylonite and ultramylonite textures in thin sections of the fault rocks. The zone of fault-associated deformation varies from a few metres across at Garvald to over 1 km at Slieve Glah. The fault thus differs from other tract-defining faults in the Southern Uplands, particularly in its clear evidence of ductile, quasi-plastic, deformation at depth, in its lack of associated imbrication, in its significant refolding and overprinting of the regional S1 cleavage and in its uniquely large stratigraphic effects.The main fabric-generating movement postdates the regional, accretion-related, S1 cleavage but predates minor Caledonian (c. 400 Ma) intrusions. For its entire length the fault separates the Northern Belt, with proof only of Upper Ordovician turbidites, and the Central Belt, where turbidite deposition began in the Silurian. The age of the base of the turbidites decreases southward by some six graptolite zones at the fault trace. The fault thus either (a) excises the equivalent of four tracts from a single accretionary-prism terrane, or (b) juxtaposes two distinct terranes, one of late Ordovician and the other of Silurian age. In either event the sinistral slip is probably in excess of 400 km.
TL;DR: In this article, poly(ethylene oxide), polystyrene and LicF 3 SO 3 have been used to improve the physical strength of electrolytes without seriously impairing the conductivity at temperatures above 60 °C.
TL;DR: Observations and analyses of larval settlement of under-stone cryptic epifaunal assemblages on the west coast of Scotland found the qualitative similarity of intertidal to sublittoral settlement was particularly striking, but this was overwhelmed by quantitative contrasts.
TL;DR: Temperature-dependent, seasonal deep-shallow migration can explain both the local returns and the long distance migrations of mature lobsters in the Bay of Fundy and the Gulf of Maine and the adjoining Continental Shelf and slopes.
Abstract: Of the 18 359 American lobsters (Homarus americanus) tagged and released at three locations in the Bay of Fundy during 1977–1980, 5 375 lobsters (29.3%) were recaptured within 6 yr of release. Mature lobsters (≧95-mm carapace length, CL) on average moved significantly greater distances than immature lobsters ( 92.6 km (50 nautical miles) from the release sites; the farthest distance moved was 798 km for a male at liberty for 3.5 yr. Examination of the direction of movements indicates some intermixing of lobsters within the Bay of Fundy, and throughout the Gulf of Maine and the adjoining Continental Shelf and slopes. Mature lobsters were recaptured in deeper waters during winter than during summer. The seasonal shallow-deep migration of mature lobsters in the Bay of Fundy is possibly associated with maximizing degree-days for molting, growth, gonadal development, and egg development. In some areas, mature females on average moved farther and seasonally earlier into deeper waters than mature males. Although the seasonal migration resulted in many lobsters returning to the original release area year after year, some lobsters made extensive long-distance movements away from the Bay of Fundy. Temperature-dependent, seasonal deep-shallow migration can explain both the local returns and the long distance migrations of mature lobsters in the Bay of Fundy and the Gulf of Maine. To achieve appropriate seasonal temperature regimes, mature lobsters have to move different distances and directions, depending on local topography.
TL;DR: It is confirmed that Littorella uniflora is faster growing and has a greater response to increasing nutrients than Lobelia dortmanna L., and this is used to explain its greater tolerance of mesotrophic environments.
TL;DR: Various methods are available for investigating temporal characteristics of behaviour and neural processing, and some theoretical and practical problems are discussed.
TL;DR: The potential for ATP generation via creatine-phosphate hydrolysis is enhanced in N. neglecta, while glycolytic capacity is relatively reduced and this is an unusual pattern of ATP production and places severe constraints upon the behavior of the fish.
Abstract: Immediate-energy-supply pathways were analysed during burst-swimming in white muscle of the Antarctic fish Notothenia neglecta, (collected during Austral summer 1984 near Signy Island, South Orkneys). Selected enzyme activities were determined, and tissue metabolites were measured, before and after 3 min of burst-work. The activity of glycolytic enzymes is very low compared to that in other fish, while the activities of creatine phosphokinase, adenylate kinase and AMPdeaminase are relatively high. Concentrations of metabolites associated with cellular energy status declined with exercise. At the same time, there was no change in the concentrations of most of the glycolytic metabolites measured (including glycogen, glucose and lactate), while [creatine phosphate] declined and [inosine monophosphate] increased. These observations were used to propose that the potential for ATP generation via creatine-phosphate hydrolysis is enhanced in N. neglecta, while glycolytic capacity is relatively reduced. This is an unusual pattern of ATP production and places severe constraints upon the behavior of the fish. While the capacity for very short-term, high-power-output swimming is increased, the capacity for medium-duration swimming is reduced. Ecological repercussions are discussed.
TL;DR: Estradiol treatment at 10 degrees stimulated the growth of liver as determined by the increase in liver somatic index and amounts of total hepatic protein, RNA, and nuclear count, and only RNA increased above the level of the untreated control fish.