Showing papers by "University of Exeter published in 1975"
TL;DR: Consideration of the tissue reaction to this material, theoretical calculation of the heat output from polymerising acrylic and interface temperature profiles, experimental observations of interface temperatures and maximal temperatures at polymerisation, together with clinical observations, all lead to the view that the bone necrosis is not a consequence of thermal damage, which is unlikely to be a cuase of failure of prosthetic fixation.
Abstract: Bone necrosis adjacent to self-curing polymethylmethacrylate is a matter of accepted fact. Among the possible causes are mechanical and vascular damage from the preparation of the bone cavity, chemical damage from the monomer and free radicals in the cement dough, and thermal damage from the heat of polymerisation, occurring in this order. Consideration of the tissue reaction to this material, theoretical calculation of the heat output from polymerising acrylic and interface temperature profiles, experimental observations of interface temperatures and maximal temperatures at polymerisation, together with clinical observations, all lead to the view that the bone necrosis is not a consequence of thermal damage, which is unlikely to be a cuase of failure of prosthetic fixation. Temperatures recorded from within polymerising acrylic masses are related primarily to the amount of monomer polymerising and are of no clinical significance in the fixation of prostheses. Interface temperatures are related primarily to the surface area of the interface and the thermal characteristics of the cooler material.
181 citations
TL;DR: In this article, the authors briefly present results from several Devon catchments which demonstrate the complexity of variations in the chemical concentration of river water during flood flows, showing that some solutes may exhibit variable response, evidencing increased and decreased concentrations during different events.
148 citations
87 citations
TL;DR: It can be concluded that the newborn baby possesses the ability to fixate binocularly an appropriately presented stimulus, and has the basic requirements for binocular vision.
79 citations
TL;DR: An analysis of response latency in the vicinity of errors supports a conclusion that error detection is very rapid and the (inferred) incidence of detection suggests that it is based upon a comparison process rather than an estimate of response likelihood.
Abstract: Recent studies have used errors in speech and typing as a source of evidence for the hypothesis put forward by Lashley (1951) that response is hierarchically organized. The present study continues this line of inquiry on typing, using both the form of the error and its latency as data. Earlier models to account for the latency of typing have postulated two stages of output processing and with a slight modification to the notion of a stage it is shown that they can also account for the error data. Suggestions are made on the nature of codes represented in each stage and on the aetiology of errors. An analysis of response latency in the vicinity of errors supports a conclusion that error detection is very rapid and the (inferred) incidence of detection suggests that it is based upon a comparison process rather than an estimate of response likelihood.
76 citations
TL;DR: In this article, a wide range of allylic derivatives of both silicon and tin were required, and the preparation of these in greatly improved yield by a low temperature modification of the hydrolysis stage of the Grignard procedure.
74 citations
TL;DR: Copper(I) complexes of approximate composition (CuCN) 4 ·(DMF) 2 ·RR′C(OH)CCBr have been isolated from copper cyanide and 1-bromopropyn-3-ols in dry dimethylformamide (DMF), which gives 4-hydroxybutynenitriles in about 60% yield.
67 citations
TL;DR: The study shows that the obstruction if functional in nature and is due to the tightening of the bladder neck as the detrusor contracts, and is perhaps most often thought to result from fibrosis but a number of studies--for example Baadenoch (1949)--have shown no associated increase in fibrous tissue.
Abstract: There is no dispute that there exists, in men, a condition of obstruction at the bladder neck in the absence of fibrous stricture or prostatic enlargement. The condition was clearly described by Guthrie (1836) and Young (1913) reported the results ff punch resection operation in over 50 cases. The large measure of success now achieved following resection of the bladder neck in these patients has perhaps been allowed to mask our ignorance of the nature of the abnormality and thus discourage studies of its cause. It is perhaps most often thought to result from fibrosis but a number of studies--for example Baadenoch (1949)--have shown no associated increase in fibrous tissue. Certainly the condition is in no way similar to the hard fibrous stricture seen more often in the distal urethra, or at the bladder neck as an occasional complication of prostatectomy. Our study shows that the obstruction if functional in nature and is due to the tightening of the bladder neck as the detrusor contracts.
66 citations
01 Jan 1975
TL;DR: In the field of trace fossils, many different kinds of classification are possible as mentioned in this paper, including preservational (stratinomic), behavioral (ethological), and phylogenetic (taxonomic).
Abstract: Classification is one of the tools of scientific discovery, no less so in the study of trace fossils than in any other science. Many different kinds of classification are possible. Simple descriptive classifications, although better than nothing, are of very limited value. Trace fossils have three distinct and significant aspects, to each of which a unique classification attaches: (1) the preservational (stratinomic), which treats of the origin of the fossil in the rocks, (2) the behavioral (ethological), which treats of the biological function represented in the fossil, and (3) the phylogenetic (taxonomic), which is concerned with the identity of the organism that produced the fossil.
64 citations
TL;DR: In this article, the authors used a sparker as a source of seismic signals and an 80 kHz hydrophone as a receiver for well-to-well seismic measurements, which were adapted to civil engineering problems.
Abstract: Well–to-well seismic measurements are adapted to civil engineering problems by use of a sparker as a source of seismic signals and an 80 kHz hydrophone as a receiver. For display a Tektronix 549 oscilloscope is used. Field application shows that the delineation of interfaces between homogeneous strata and the detection and delineation of localized and irregular features is possible from inter-well travel times. In-situ measurement of the compressional wave velocity in a medium is often complicated by refraction and wave guide effects. The degree of fracturing cannot be estimated from travel time measurements alone in a tightly jointed, saturated, rock mass, but it may be possible to correlate variations in pulse shape and length with this parameter.
50 citations
TL;DR: The natural diet of a population of Cepaea nemoralis living in a sand dune system in southwest England was investigated by field observations and examination of crop and faeces contents, with high variability in the results linked to the live weight and activity cycles of the snails.
Abstract: The natural diet of a population of Cepaea nemoralis living in a sand dune system in southwest England was investigated by field observations and examination of crop and faeces contents. The food consisted of dead material from the commoner plants on the site. Very little green matter was eaten and there was little evidence for seasonal variation in the diet.
TL;DR: In this paper, the onset of free convection at upward facing horizontal surfaces adjacent to a free fluid environment has been studied using the electrochemical system involving the electrodeposition of Cu 2+ ions.
TL;DR: In this paper, two experiments were conducted in which first-year students were asked to read a passage of prose under different conditions, chosen to represent realistic study strategies, and the results of the second experiment indicated that the requirement to undertake recording activities has a negative effect upon learning only in circumstances whereby such a requirement imposes constraints upon learners' strategies.
Abstract: Summary. TWO experiments were conducted in which first-year students were asked to read a passage of prose under different conditions, chosen to represent realistic study strategies. In the first experiment 86 students were allocated to three main conditions of reading, copying and summarising. The summarising activity, contrary to expectations, did not lead to greater recall than reading alone. The results of the second experiment, in which some of the 96 students read the material and others listened to it, indicated that the requirement to undertake recording activities has a negative effect upon learning only in circumstances whereby such a requirement imposes constraints upon learners' strategies.
TL;DR: It is described here an effect which does not seem to have been reported previously, even though it must be familiar to certain craftsmen, and which is claimed that eminences no higher than 0.001 mm etched on to smooth glass can be detected.
Abstract: DRAWING the finger tips across a smooth surface usually induces sensations of pressure, warmth or cold, and roughness or smoothness. Any abrupt discontinuity is easily felt: it has been claimed that eminences no higher than 0.001 mm etched on to smooth glass can be detected, provided some movement of the finger tips is permitted1. We describe here an effect which does not seem to have been reported previously, even though we think that it must be familiar to certain craftsmen.
TL;DR: The effect of forced aeration in stimulating sporulation in aquatic Hyphomycetes is interpreted as due to two phenomena: the time taken for spore development and detachment is several hours shorter at high aeration rates and the number of conidiophores per unit area of culture surface is significantly greater at highaeration rates.
Abstract: The effect of forced aeration in stimulating sporulation in aquatic Hyphomycetes is interpreted as due to two phenomena. The time taken for spore development and detachment is several hours shorter at high aeration rates than at low aeration rates. The number of conidiophores per unit area of culture surface is significantly greater at high aeration rates. This is probably due to increased hyphal branching induced by turbulence. Cultures which have been induced to form higher numbers of conidia by rapid aeration continue to do so when the aeration rate is decreased.
TL;DR: It can be shown that theoretical calculations of these sources of error, calculations based both on the anatomy of the eye, and on the optics involved, produce good agreement with their empirically derived magnitudes.
TL;DR: All graminaceous isolates were pathogenic on wheat seedlings and significant differences in pathogenicity were recorded, particularly within barley and tall fescue cultivars.
Abstract: SUMMARY
Graminaceous species and cultivars were screened under glasshouse conditions for reaction to inoculum of Septoria tritici. An agar plate test was used to record positive infections and successful isolations were subcultured on to Czapek Dox V-8 agar under continuous near-ultraviolet irradiation to induce spore production for pathogenicity tests on the wheat cv. Maris Ranger. Koch's postulates were followed for each graminaceous isolate. S. tritici was recorded on 11 species, but pycnidial development was restricted to eight species. Differences in reaction to S. tritici were observed within barley and tall fescue cultivars. All graminaceous isolates were pathogenic on wheat seedlings and significant differences in pathogenicity were recorded. The ro1e of graminaceous species as alternative hosts in the epidemiology of S. tritici on wheat is discussed.
TL;DR: In this paper, a new indenter was designed to eliminate the anisotropy normally observed in hardness measurements on single crystals when the Vickers, Berkovich and Knoop indenters are used.
Abstract: A new indenter has been designed to eliminate the anisotropy normally observed in hardness measurements on single crystals when the Vickers, Berkovich and Knoop indenters are used. It has the form of a regular pentagon based pyramid with an angle of 65 degrees between each facet face and its geometric axis. Preliminary measurements show that this indenter gives reproducible results on crystalline materials of widely differing hardness from lead (0.05 GN m-2) to diamond ( approximately 100 GN m-2), which are directly comparable with those of the conventional pyramidal indenters. Moreover, these results are independent of the orientation between indenter facets and the crystallographic characteristics of the indented surface.
01 Jan 1975
TL;DR: In the last two chapters we have considered critically how religion appeared to Wittgenstein in the light firstly of the Tractatus, which was published in 1921, and secondly of the empiricist verificationism with which he seems to have sympathised during the late 1920s and early 1930s as discussed by the authors.
Abstract: In the last two chapters we have considered critically how religion appeared to Wittgenstein in the light firstly of the Tractatus, which was published in 1921, and secondly of the empiricist verificationism with which he seems to have sympathised during the late 1920s and early 1930s. Now we must turn to such evidence as we have concerning the views on religion which he held in the light of his late philosophy. This evidence consists mainly of notes taken by students who attended lectures on religious belief which he gave in Cambridge during 1938. Cyril Barrett, who compiled and published them in a volume entitled Lectures and Conversations on Aesthetics, Psychology and Religious Belief Oxford, 1966), is careful to emphasise in his preface that they are not Wittgenstein’s own lecture notes, that he neither now nor checked them, and that he might not have approved of their publication in the present form. However, those who book them down were amongst Wittgenstein’s most ardent disciples and we may safely assume that they have provided a faithful record of his teaching.
TL;DR: The possibility of conventional negative resistance is demonstrated, and experimental observations of relaxation oscillations are presented and interpreted in terms of a negative-resistance region.
Abstract: Observations of flow through a collapsible tube with two elastic constrictions in series show that it exhibits a type of negative-resistance behaviour, where increasing the resistance of the downstream constriction decreases the overall resistance to flow. This behaviour occurs because the resistance to flow of an elastic constriction is greater in the transonic configuration than in the sonic, and it cannot be accounted for by the 1-dimensional theory of flow through such tubes. The possibility of conventional negative resistance is demonstrated, and experimental observations of relaxation oscillations are presented and interpreted in terms of a negative-resistance region.
TL;DR: Energy flux in a population of Cepaea nemoralis L. living on a sand dune system was estimated in 1970 and 1971 and mortality rates of the small animals was high and density of the next size class was much lower.
Abstract: Energy flux in a population of Cepaea nemoralis L. living on a sand dune system was estimated in 1970 and 1971. Numbers and dynamics of the adults were studied by a capture-mark-recapture method, juveniles by quadrat sampling. Adult numbers were around a mean of 2.14 m-2 (mean annual biomass 14.7 kJ m-2 1970; 13.4 kJ m-2 1971). Eggs were laid in June, July and August and peak numbers of small juveniles (<6 mm) were present in October (20.7 m-2 1970; 7.8 m-2 1971). Mortality rates of the small animals was high and in the following season (1971) density of the next size class (6–11 mm) was much lower (4.9 m-2). Mean annual biomass of the whole population was 17.0 kJ m-2 in 1970 and 16.4 kJ m-2 in 1971. Growth rates were slow and variable. Adult production was calculated as the yield to carnivores and scavengers plus the continuous mucus production which was almost half the total. Juvenile production was calculated from quadrat sampling data. Total population production was 34.3 kJ m-2 in 1970 and 25.9 kJ m-2 in 1971. Adult respiration was measured in an open flow respirometer with gas analysis by gas chromatograph. Measurements were made in 1971 on field acclimated animals. Juvenile respiration measurements were made in Warburg respirometers. Population respiratory losses were 62.8 kJ m-2 and 41.8 kJ m-2 in the 2 years. In the calculation of population respiration, allowance was made for low metabolic rates during periods of aestivation and hibernation. Population activity was reduced by 90% after 5 days without rain. Population consumption, was estimated at 316.6 kJ m-2 and 239.0 kJ m-2 and assimilation efficiencies were from 30–40% on natural foods. Annual energy budgets were constructed and energy flux (P+R) was 97.0 kJ m-2 in 1970 and 77.6 kJ m-2 in 1971. The plot of log respiration against log production fell lower than that for most long-lived poikilotherms due to the inflation of the production estimate by mucus production.
TL;DR: Rates of relevant physiological processes were found for both sexes, both uninfected and bearing various worm burdens, and body weight, change in weight during an experiment, and temperature were the most closely linked variables to these rates.
TL;DR: A double-isotope technique for simultaneously measuring the per cent incorporation of two precursors into a metabolite is described and has been used to show that ornithine is a more efficient precursor than arginine for the biosynthesis of retronecine.
TL;DR: A range of aminomethyl substituted trioganotins have been prepared by four basic routes: direct action (iodmethyl)trimethyltin or (iodomethemyl)triphenyltin on primary and secondary amines in ether solution (method A), on primary amines on the presence of triethylamine (method B), on the potassium salts of amines and on the amine in ether solutions (method C), and finally by the reaction of N,S-acetals with variou trialkyltinlithium
TL;DR: In outdoor enclosures it is shown that weather and time of the year both modify the activity pattern and the nature of the activity in an indoor residential maze is described and the effects of a food shortage noted.
Abstract: The activity of Wood mice, Apodemus sylvaticus, was monitored by light beams and photoelectric cells placed in runways. In outdoor enclosures it is shown that weather and time of the year both modify the activity pattern. The nature of the activity in an indoor residential maze is described and the effects of a food shortage noted.
TL;DR: In the past, the superficial similarity of the ethnomethodologists' interest in small scale interaction has led to comparisons with the work of Goffman and the symbolic interactionists as discussed by the authors.
Abstract: Ethnomethodology should not be mistaken for just one more variety of microsociology It is much more: it represents a comprehensive challenge to some of sociology's most general assumptions In the past, the superficial similarity of the ethnomethodologists' interest in small scale interaction has led to comparisons with the work of Goffman and the symbolic interactionists (Gouldner 1971, Denzin 1971, Gidlow 1972), but ethnomethodologists have vehemently rejected such parallels (Douglas 1971:21, Zimmerman and Wieder, 1971) The emergence of ethnomethodology, as both Bauman (1973b:31) and Goldthorpe (1973) recognize, represents a renewal of the Methodenstreit which flared in German sociology around the turn of the century The ethnomethodologists reject deductive explanation of the "covering law" kind in social science, emphasize the necessity of grasping the "meanings" which social interaction has for those participating in it, and are preoccupied with the uniqueness of every social situation' Though recast in subtle forms, the old arguments for a rigid distinction between the natural and social sciences are easily recognizable The philosophical roots of ethnomethodology are two-fold Ethnomethodologists themselves most prominently claim intellectual ancestry from the social phenomenology of Alfred Schutz2 Yet Schutz has other sociological followers most notably Berger and Luckmann (1967) whose work represents a much less drastic break with the interests of "conventional" sociology, and from whom ethnomethodologists are at pains to emphasize their differences What is really more distinctive of ethnomethodology is its debt to Wittgensteinian "ordinary language" philosophy The nature of these twin debts will be examined below Of ethnomethodology as a school of thought within sociology, Harold Garfinkel is usually acknowledged to be the founder Although ethnomethodology did not attract very wide attention among sociologists generally until a spate of publications by Garfinkel and his fol-
TL;DR: In this article, the authors analyse the scoring assumptions made by Linton for various land use/landforms combinations and the possibility of extending the model outside Scotland by means of a slide experiment and show that the method is extendable and that it is land use rather than landform which is in need of major modification.
Abstract: Gilg A. W. (1975) The objectivity of Linton type methods of assessing scenery as a natural resource, Reg. Studies, 9, 181–191. Previous studies have shown that Linton's method has potential for development. The purpose of this paper is to analyse (a) the scoring assumptions made by Linton for various land use/landforms combinations and (b) the possibility of extending the model outside Scotland. This is achieved by means of a slide experiment. The results show that the method is extendable and that it is land use rather than landform which is in need of major modification, a conclusion also reached by a study in Lanarkshire. Using this evidence a revised method is proposed which should be applicable to the staff of the new local planning authorities engaged in landscape evaluation exercises as part of the preparation of structure plans.