Showing papers by "Keele University published in 1982"
TL;DR: The problem of sequencing jobs on a single machine to minimize total tardiness is considered and an algorithm, which decomposes the problem into subproblems which are then solved by dynamic programming when they are sufficiently small.
306 citations
TL;DR: These findings are consistent with the effects of such current stimulation in patients with tinnitus of peripheral origin and support the hypothesis that the neural correlate of such tinnitis is hyperactivity at the cochlear nerve level.
Abstract: Anaesthetized cats were given 400 mg/kg sodium salicylate i.v. producing blood levels in excess of 300-400 mg/kg. Within 10 min of injection, thresholds of fibers had risen by values ranging from 13 to 21 dB. The elevation in thresholds progressed rapidly over the subsequent 5 or so hours, reaching a plateau in about 10 h. The Q10 dB values for tuning of the cochlear fibres decreased by a factor of 3-4 on average over the same period. Likewise, the dynamic range of response was significantly reduced. These effects on the cochlear fibres were reflected in the elevation of the gross cochlear action potential thresholds. In contrast to the findings with other types of cochlear pathology, the mean discharge rate of the subpopulation of cochlear fibres having discharge rates above 20 sp/s was significantly increased by an average of 10-20 sp/s. There was a tendency for this increase to be more marked for fibres with higher characteristic frequencies and to be inversely related to threshold. In addition, 63% of fibres had anomalous temporal patterns of spontaneous activity. In view of the relevance of these data on the ototoxic effects of salicylates for our understanding of tinnitus, the effects of direct electrical current stimulation via the round window have been studied. Positive currents up to at least 600 microA suppressed the spontaneous and evoked activity of all cochlear fibres studied in the normal cochlea. These findings are consistent with the effects of such current stimulation in patients with tinnitus of peripheral origin and support the hypothesis that the neural correlate of such tinnitus is hyperactivity at the cochlear nerve level.
134 citations
TL;DR: Two or possibly three separate processes are suggested as the basis for detailed shape perception, and high relative efficiencies are obtained for all curved lines with an orientation range of less than 40 deg.
125 citations
TL;DR: N-(2-Hydroxypropyl)methacrylamide copolymers bearing oligopeptide side-chains terminating in p-nitroaniline (NAp) were incubated with rat liver lysosomal enzymes in the presence of the thiol glutathione and degradation was partially or totally inhibited by leupeptin.
Abstract: N-(2-Hydroxypropyl)methacrylamide copolymers bearing oligopeptide side-chains terminating in p-nitroaniline (NAp) were incubated with rat liver lysosomal enzymes in the presence of the thiol glutathione, and the rate of p-nitroaniline release was measured. Twelve of the 16 side-chains investigated were hydrolysed to release p-nitroaniline and in all but one case degradation was partially or totally inhibited by leupeptin. The effect of substrate concentration on the degradation of the most readily cleaved side-chain, -Ala-Gly-Val-Phe-NAp, was measured.
97 citations
TL;DR: Tuning properties and spontaneous discharge rate of single cochlear fibres in the anaesthetized cat were determined during short‐ and long‐term poisoning of the cochlea by locally and systemically applied furosemide.
Abstract: 1. Tuning properties and spontaneous discharge rate of single cochlear fibres in the anaesthetized cat were determined during short- and long-term poisoning of the cochlea by locally and systemically applied furosemide.2. With intra-arterial administration of furosemide, short-term reversible elevation occurred of the low threshold sharply tuned ;tip' segment of the frequency threshold (;tuning') curve (f.t.c.) by up to 40 db, without substantial changes in the threshold of the low frequency ;tail' segment of the f.t.c. These changes could occur in part without changes in the spontaneous activity and entirely without changes in the maximal evoked activity. These effects were observed in all fibres examined, the characteristic frequencies of which ranged from 3.5 to 31 kHz.3. Intracochlear administration of furosemide in 0.9 mM concentrations produced similar changes, but these were not reversible.4. The changes correlated with the depression of the amplitude of the gross cochlear action potential. The cochlear microphonic potential, however, was either unchanged, or only slightly reduced.5. In long-term furosemide poisoning of the cochlea, fibres with anomalous response properties were found alongside fibres having normal tuning. The former exhibited either reduced excitability of the low threshold tip segment, or a tip segment attenuated in both excitability and threshold.6. It is concluded that the selective effects of furosemide on the tip segment of cochlear fibre f.t.c.s offer further evidence for a physiologically vulnerable ;second filter' in the cochlea. The selective influence of the furosemide on the low threshold tip segment provides support for the hypothesis that the normal f.t.c. is generated by two largely independent processes: one vulnerable, low threshold and sharply tuned, and the other less vulnerable, but high threshold and more broadly tuned.7. The findings, obtained with an agent known to produce reversible impairment of hearing in man, provide direct physiological evidence in support of the hypothesis that in sensorineural hearing loss of cochlear origin the frequency selectivity of cochlear nerve fibres is impaired.
94 citations
TL;DR: The reason why "populism" has remained such a confused notion is that two different strategies can be adopted in trying to clarify it, and the more intuitively appealing of the two does not work as discussed by the authors.
Abstract: The reason why ‘populism’ has remained such a confused notion is that two different strategies can be adopted in trying to clarify it, and the more intuitively appealing of the two does not work. A...
82 citations
81 citations
TL;DR: In this paper, a single substance from the venom gland of the ant Myrmica rubra L. was identified as 3-ethyl-2,5-dimethylpyrazine by microchemical methods and by comparison with the synthetic compounds.
73 citations
01 Feb 1982
TL;DR: In this paper, Spectroscopic Analysis of Drug-Nucleic Acid Interaction is presented, where the authors present a set of properties of drug-nucleic acid interactions and their relationships.
Abstract: (1982). Spectroscopic Analysis of Drug-Nucleic Acid Interaction. Critical Reviews in Biochemistry: Vol. 12, No. 2, pp. 103-132.
71 citations
TL;DR: Frigid mutants of Dictyostelium discoideum appear to initiate development when starved, but the process is blocked at an early stage, unlike the former group of mutants.
Abstract: To find mutants of Dictyostelium discoideum that are unable to respond to exogenous cAMP signals (frigid mutants), amoebae of 218 independent aggregation-deficient mutants were treated in suspension with artificial pulses of cAMP and screened for the capacity to form EDTA-resistant cohesion sites. Eleven frigid mutants were identified and further characterized. Using parasexual genetic techniques, these strains were assigned to five complementation groups (fgdA-E) and the fgd loci were mapped in three linkage groups: fgdA and D in group II, fgdC in group III, and fgdB and E in group VII. Biochemical and physiological experiments with these strains indicated that fgd mutants are of two general types. When starved, strains in groups fgdB, D, and E failed to produce detectable levels of membrane-associated cAMP phosphodiesterase, surface cAMP receptors, or extracellular phosphodiesterase inhibitor, and the cells continued to respond chemotactically to folate. Thus, these strains are probably arrested in the vegetative phase or very early in development. In contrast, strains in groups fgdA and C produced low levels of cAMP receptors and secreted phosphodiesterase inhibitor. Moreover, after starvation, some of these mutants elicited a weak chemotactic response to cAMP. Therefore, unlike the former group of mutants, these strains appear to initiate development when starved, but the process is blocked at an early stage.
65 citations
15 Jul 1982
TL;DR: In this paper, an infrared multiple photon dissociation (pulsed CO 2 laser) of CH 3 NH 2, CH 3 CN, and cyclo-C 3 H 6 was observed by laser induced fluorescence.
Abstract: The reaction of CH with N 2 is the initial step in what is thought to be one of the principal mechanisms for the formation of nitrogen oxides in flames, and reactions of CH with these oxides also influence the final composition of the burnt gases. In order to study these reactons, we produced CH radicals by infrared multiple photon dissociation (pulsed CO 2 laser) of CH 3 NH 2 , CH 3 CN, and cyclo-C 3 H 6 . The subsequent removal of CH by reaction with NO, N 2 O, NO 2 and N 2 was observed by laser induced fluorescence. For the first three reactions, the rates at 300 K are fast: k NO = (2.0 ± 0.3) × 10 −10 cm 3 s −1 k N 2 O = (7.8 ± 1.4) × 10 −11 cm 3 3 s −1 , and k NO 2 = (1.67 ± 0.11) × 10 −10 cm 3 s −1 . The reaction with N 2 is endothermic and the observed pressure-dependent rate constants at 300 K are interpreted in terms of a collision-stabilised recombination mechanism, for which we estimate the limiting low press-are rate constant k 3 = (2.6 ± 0.3) × 10 −31 cm 6 s −1 and the high pressure rate constant k 2 = (6.3 ± 1.3) × 10 −13 cm 3 3 −2 .
TL;DR: Experiments are reported in which the perceived motion of an extrafoveal grating slowed down to zero and that of anExtraFoveal sector disc became fragmented upon prolonged fixation.
Abstract: Experiments are reported in which the perceived motion of an extrafoveal grating slowed down to zero and that of an extrafoveal sector disc became fragmented upon prolonged fixation.
TL;DR: The dynamic range over which fine intensity discrimination is possible has been reported to be largely unaffected by limitation of the spread of neuronal activity to neighbouring frequency regions by bandstop noise masking, but this is examined in the presence of a bandstop masking noise designed to be comparable to that employed in the psychophysical experiments.
TL;DR: In this article, the authors investigated the stress response of the upper lithosphere to a power-law stress and temperature dependent viscoelastic properties and found that the rate and extent of stress decay and associated stress amplification is greatly dependent on the lithosphere geotherm.
Abstract: Summary Lithosphere subjected to an externally derived horizontal stress undergoes creep in the lower lithosphere resulting in the decay of lower lithosphere stress and the associated amplification of stress within the upper lithosphere. This stress response of lithosphere has been investigated for a lithosphere model with power-law stress and temperature dependent viscoelastic properties. The rate and extent of stress decay and associated stress amplification is greatly dependent on the lithosphere geotherm.
Oceanic lithosphere subject to an applied stress of ± O.1 kb undergoes upper lithosphere stress amplification of × 1.5, × 1.8 and × 2.0 at 104, 106 and 108 yr respectively. At 106 yr the effective lithosphere thickness is reduced to approximately 40 km. The stress decay and amplification proceeds more rapidly for an applied stress of ± 1.0 kb and in the case of a tensile applied stress results in some upper lithosphere fracture. For continental and Basin and Range type lithosphere the comparable stress amplification at 106 yr, for a stress of ± 0.1 kb, is × 2.0 and × 6.5 with effective lithosphere thicknesses of 60 and 20 km respectively. The large values of stress amplification for the Basin and Range lithosphere result in complete upper lithosphere fracture which gives rise to a cyclic process of upper lithosphere faulting and lower lithosphere creep in which extensive lithosphere deformation can occur.
The stress amplification process also occurs for stresses generated by lateral density contrasts. For an isostatically compensated plateau uplift structure, deviatoric stresses of the order of 1 kb can be generated in the upper lithosphere by this process and are sufficient to cause tensile fracture of the upper lithosphere. The response of viscoelastic lithosphere to constant geometry bending stresses has also been examined and results in substantial but not complete reduction of the bending stresses.
TL;DR: The paper develops the view that the major challenge cybernetics poses conventional organization theory rests in its epistemological implications and these have fundamental consequences for the way the authors view organizations and their mode of operation.
Abstract: Based on the view that theorizing is metaphorical, this paper examines the impact of cybernetic imagery on the study of organizations. Imagery treating organizations as "black boxes," "thermostats," "decision-makers," "morphogenic systems," "learning systems," and the concept of "organizational ecology" is explored. Developing the distinction between "cybernetics as technique" and "cybernetics as epistemology, " it is suggested that organization theory has for the most part used cybernetics in the former sense. The paper develops the view that the major challenge cybernetics poses conventional organization theory rests in its epistemological implications. Systematically developed, these have fundamental consequences for the way we view organizations and their mode of operation.
TL;DR: A good deal of emergency legislation was passed until the 1820s, but thereafter a marked decline in the incidence and severity of violent disturbance, and in the violence of the government's responses, set in this paper.
Abstract: Not the least significant constitutional difference between Britain and many continental states in the nineteenth century lay in the sphere of formal arrangements for the exercise of power during civil emergencies. Britain had no clearly understood concept of notrecht or of 'state of siege’. This omission certainly reflected the absence of foreign invasion as much as the feebleness of domestic revolutionary threats. Internal emergencies occurred, indeed, with a frequency hard to square with the old Whig interpretation; but while they often alarmed the authorities, none of them proved so formidable as not to be amenable to control by the civil power backed up by fairly small numbers of troops. A good deal of emergency legislation was passed until the 1820s, but thereafter a marked decline in the incidence and severity of violent disturbance, and in the violence of the government's responses, set in. The threat of revolution in Britain itself, in so far as it had ever existed, had faded. The terrible uncertainties revealed by the 1831 Bristol riots could be optimistically put aside: magistrates could get by with ‘reading the Riot Act’ and trusting to luck, and perhaps a few dragoons or yeomanry.
TL;DR: Despite the presence of a host cellular response parasites survive apparently unharmed as long as the host lives, and three leucocyte cell types (L1, L2 and L3) have been observed.
Abstract: . Infections of roach, Rutilus rutilusL., with the plerocercoid larva of Ligula intestinalis result in a pronounced host cellular response which consists of a leucocyte and connective tissue component. Using ultrastructural, histochemical and tracer techniques, three leucocyte cell types (L1, L2 and L3) have been observed. L1 cells, the most numerous cell type, pass through a number of characteristic developmental stages. Phagocytosis occurs in stages 1, 2 and 3. Stages 1 and 2 contain predominantly primary lysosomes and secondary lysosomes respectively, and in cells of stage 3 residual bodies are found which may be released following disruption of the cell at stage 4. The lysosomes and residual bodies do not contain acid phosphatase although arylsulphatase activity is present in all secondary lysosomes and residual bodies and in a few primary lysosomes. L1 cells are thought to be macrophages. L2 and L3 cells are relatively rare. The former contain granules resembling those found in mammalian eosinophils but which themselves are not eosinophilic or acid phosphatase and arylsulphatase positive. L2 cells are phagocytic and are thought to be neutrophils. L3 cells are also phagocytic and may represent macrophage precursors. Despite the presence of a host cellular response parasites survive apparently unharmed as long as the host lives. The significance of this is discussed.
TL;DR: In this article, the Crown and Cortes in Castile, 1590-1665, were discussed in the context of the Parliaments, Estates and Representation.
Abstract: (1982). Crown and Cortes in Castile, 1590–1665. Parliaments, Estates and Representation: Vol. 2, No. 1, pp. 29-45.
TL;DR: In this article, the variational methods applied to bound-state and scattering problems are discussed and reviewed in the framework of a unified variational method, and a unified method is proposed.
TL;DR: For both experts and novices, writing is viewed as a primarily assimilative process, the difficulty of which is largely determined by goals the writer imposes on the activity as mentioned in this paper.
Abstract: Writing, for both experts and novices, is viewed as a primarily assimilative process, the difficulty of which is largely determined by goals the writer imposes on the activity. Novices assimilate w...
TL;DR: In this article, it is shown that it is possible to phase the X-ray reflections from a macromolecular crystal which contains one heavy atom per molecule without having recourse to the conventional method of multiple isomorphous replacement, by making use of anomalous dispersion effects alone.
Abstract: In principle, it is possible to phase the X-ray reflections from a macromolecular crystal which contains one heavy atom per molecule, without having recourse to the conventional method of multiple isomorphous replacement, by making use of anomalous dispersion effects alone1. To do this, it is necessary to measure each reflection over a narrow range of wavelengths centred on an absorption edge of the heavy atom, where f′ and f″, the real and imaginary anomalous components of the scattering factor, are varying rapidly. The availability of powerful synchrotron radiation sources with a continuous energy spectrum has stimulated interest in such phasing methods, but previously experiments1 have been limited to making measurements on only one reflection at a time and/or to measuring at only a few discrete wavelengths near the absorption edge. We are developing a method at the Daresbury Synchrotron Radiation Source (SRS) which produces an energy profile along an axis of each and every diffraction spot in a screenless oscillation photograph. We show here that the approach is feasible using a single crystal o heptahydrido bis (diisopropylphenyl)phosphine rhenium using the LIII absorption edge of rhenium at a wavelength of 1.1772 A.
TL;DR: Some superficial-layer, texturesensitive complex cells in cat striate cortex showed a clear preference for either in-phase or antiphase relative motion, irrespective of direction of motion across the receptive field.
Abstract: Responses of superficial-layer, texturesensitive complex cells in cat striate cortex to relative motion between an oriented bar stimulus and its textured background were recorded. Some cells responded best to motion in one particular direction across the receptive field of the cell, irrespective of whether the bar and background moved simultaneously in the same (in-phase) or opposite (antiphase) directions. Others showed a clear preference for either in-phase or antiphase relative motion, irrespective of direction of motion across the receptive field.
TL;DR: Ovariectomy of the adult female Rhodnius results in a reduction of the electrical activity of the corpus cardiacum and injection of 20-hydroxy-ecdysone into ovariectomized animals increases the activity to control values.
TL;DR: The findings show that hypoinsulinism has a differential effect on the enzymatic profile of the different skeletal muscle fiber types, with those of the red gastrocnemius being most severely affected.
TL;DR: The filtering properties of single cochlear fibres have been determined in normal and kanamycin-treated guinea pigs using the reverse correlation technique, and the findings in the normal guinea pig are consistent with those obtained by others in rodents, but are not inconsistent with those from the cat, where normal filtering is more robust to high levels of stimulus noise.
TL;DR: In this article, a model for the deformation of viscoelastic lithosphere, with temperature and stress-dependent rheology, subjected to laterally applied stress for different lithosphere thermal structures is examined.
Abstract: The magnitude levels of intraplate stresses and the strength of intraplate lithosphere are critical for understanding the mechanisms of intraplate deformation. The decay of stress in the ductile lower lithosphere and its resulting amplification in the brittle upper lithosphere constitute an important mechanism for providing stress levels in the upper brittle lithosphere sufficient for fracture. Such stress transfer and the subsequent lithosphere deformation are controlled by lithosphere rheology. A model is examined here for the deformation of viscoelastic lithosphere, with temperature- and stress-dependent rheology, subjected to laterally applied stress for different lithosphere thermal structures. The geotherm is found to be of critical importance in determining the strength of the lithosphere and the extent of the resulting lithosphere deformation. For lithosphere with heat flow ⩾75 mW m−2, 0.25 kbar tensile stress is sufficient to cause geologically significant deformation, while for compressional deformation, either greater stress levels or a hotter lithosphere are necessary.
TL;DR: The results indicate that the insecticide-induced release of hormone may be mediated by the action of insecticides directly on neurosecretory cells.
TL;DR: It was shown that following internalization, the PHEA-tyramine linkage is resistant to intracellular hydrolysis and illustrated the highly efficient concentration of the tyramine derivative by yolk sac endodermal cells.
01 Oct 1982-International Journal of Human-computer Studies \/ International Journal of Man-machine Studies
TL;DR: This paper is concerned with the experience of transforming a set of repertory grid programs developed for research purposes on a large mainframe computer into an integrated system on a low-cost microcomputer.
Abstract: Direct interaction between patients and computers has now been shown to be successful and acceptable in an experimental environment. Automated psychological testing has also been widely validated against experts administering the same test. However, there are problems in making available what are essentially computer-based research tools to a diverse community of users, geographically widespread, with a range of experience of computer systems, test procedures, analytic techniques and information presenta-tion. This paper is concerned with the experience of transforming a set of repertory grid programs developed for research purposes on a large mainframe computer into an integrated system on a low-cost microcomputer. This had to be done in such a way that all aspects of the operation and many aspects of the application of the system would be self-evident to users issued with only a program disk and simple manual. It was also a requirement of some potential users that they be able to re-program the interactive dialogue with their clients to reflect the particular purpose for which a grid was being elicited: for example, personnel selection, career guidance or industrial training. Some users also wished to translate the dialogue from English into their native language. The paper also describes the techniques adopted to allow this without requiring programming knowledge on the part of the users and without undermining the integrity of the program suite.
TL;DR: In this paper, the authors examined the relationship of Type A behaviour to career experiences associated with feelings of personal failure and found that Type A behavior was significantly related to career outcomes reflecting disappointment, alienation and personal failure.
Abstract: SUMMARY This study examines the relationship of Type A behaviour to career experiences associated with feelings of personal failure (Korman and Korman, 1980). Seventy-five managers completed the Jenkins Activity Survey, a widely used paper-and-pencil index of Type A behaviour, and measures of various career experiences. The data provided concurrent validation of the Korman's model and also showed Type A behaviour to be significantly related to career outcomes reflecting disappointment, alienation and personal failure. A case is made for the inclusion of Type A in career research. Implications for careerists and their organizations are offered.