Showing papers by "Queen's University Belfast published in 1975"
TL;DR: In this article, the work functions of the bulk crystals and of silver films formed upon them by auto-epitaxy were determined photoelectrically, and the results support the Smoluchowski correlation of work function with surface atom density.
Abstract: (100) and (110) single crystals of silver were cleaned by electron and argon-ion bombardment in ultra-high vacuum. The work functions of the bulk crystals, and of silver films formed upon them by autoepitaxy, were determined photoelectrically. The bulk crystals had work functions of (4.64 ± 0.02) eV and (4.52 ± 0.02) eV respectively. The effect of the deposition of silver films was to reduce the work function, but continued cycles of deposition and annealing at 500 to 600 K caused the work function to return to a value very close to that of the bulk crystal. An annealed film of silver deposited in stages on a mica substrate at 425 K had a work function of (4.72 ± 0.02) eV, corresponding to that of the (111) silver surface. If the mica remained at room temperature during deposition, the work function was about 4.5 eV. The work function of a thick polycrystalline film of silver on quartz was (4.26 ± 0.02) eV. The results support the Smoluchowski correlation of work function with surface atom density.
223 citations
211 citations
TL;DR: In this article, the authors compared solvent-extracted chicken muscle, bovine plasma albumin (BPA) and other proteins, all severely heated in the absence of carbohydrates so as to cause a large decrease in their fluorodinitrobenzene (FDNB)-reactive lysine contents.
Abstract: 1. Studies have been made with solvent-extracted chicken muscle, bovine plasma albumin (BPA) and other proteins, all severely heated in the absence of carbohydrates so as to cause a large decrease in their fluorodinitrobenzene (FDNB)-reactive lysine contents.2. ɛ-N-(β-L-aspartyl)-L-lysine and ɛ-N-(γ-L-glutamyl)-L-lysine isopeptides were determined after enzymic digestion of heated chicken muscle, and their content was found to increase as the material was subjected to more heat treatment. Heated chicken muscle was not found to contain lanthionine. Heated BPA, on the other hand, was found to contain lanthionine but not the isopeptides. Both lanthionine and isopeptide cross-linkages were detected in most of the other heated proteins. There was some difficulty in quantifying the amounts of isopeptides formed on heat treatment, because the enzymic digestion procedure used in their isolation appeared to be incomplete. Neither lysinoalanine nor ornithinoalanine was detected in any of the test materials.3. The severely heated chicken muscle was fed to rats, and ileal and faecal digestibilities were studied. Protein digestibility was found to be greatly reduced after heat treatment, although the isopeptides themselves appeared to be at least as digestible as the total N component, total lysine, or FDNB-reactive lysine. However, the reduction in ileal N digestibility only partly accounted for the much larger reduction in nutritive value, as measured by net protein ratio ((weight loss of N-free animals + weight gain of test animals) ÷ weight of crude protein (N × 6.25) consumed by test animals). Possible reasons for this are discussed.
196 citations
TL;DR: A pleasing notation by which treelike data structures can be declared and processed is suggested; it gives the axioms which specify their properties, and an efficient implementation method is suggested.
Abstract: The power and convenience of a programming language may be enhanced for certain applications by permitting treelike data structures to be defined by recursion. This paper suggests a pleasing notation by which such structures can be declared and processed; it gives the axioms which specify their properties, and suggests an efficient implementation method. It shows how a recursive data structure may be used to represent another data type, for example, a set. It then discusses two ways in which significant gains in efficiency can be made by selective updating of structures, and gives the relevant proof rules and hints for implementation. The examples show that a certain range of applications in symbol manipulation can be efficiently programmed without introducing the low-level concept of a reference into a high-level programming language.
172 citations
TL;DR: A treatment of electron correlation has been the aim of most of the recent work in this field, and the methods which have been proposed are reviewed in this paper, where the accuracy to which energies (or at least energy differences) can be evaluated, and calculations of electron affinities and term ratios are considered.
Abstract: The general availability of electronic computers has resulted in a variety of developments in calculations of the electronic structure of atoms. The starting point is generally the Hartree-Fock approximation, which inadequately accounts for the motion of the electrons. A treatment of electron correlation has been the aim of most of the recent work in this field, and the methods which have been proposed are reviewed. The accuracy to which energies (or at least energy differences) can be evaluated, and calculations of electron affinities and term ratios are considered. The evaluation of oscillator strengths (transition probabilities) and hyperfine structure are also covered. Available atomic structure programs based on the correlation methods are discussed.
147 citations
TL;DR: In the pre-reformation period, the emphasis of the sacrament of penance lay in its providing part of a machinery for the regulation and resolution of offences and conflicts otherwise likely to disturb the peace of a community.
Abstract: When I offered to read a paper on this subject, I had a particular hypothesis in mind. I thought—perhaps it would be more honest to say, I hoped—it would be possible to show that, during a period roughly contemporaneous with the Reformation, the practice of the sacrament of penance in the traditional church had undergone a change which was important in itself and of general historical interest. The change, I thought, could roughly be described as a shift from the social to the personal. To be more precise, I thought it possible that, for the average layman, and notably for the average rural layman in the pre-reformation church, the emphasis of the sacrament lay in its providing part of a machinery for the regulation and resolution of offences and conflicts otherwise likely to disturb the peace of a community. The effect of the Counter-Reformation (or whatever one calls it) was, I suspected, to shift the emphasis away from the field of objective social relations and into a field of interiorized discipline for the individual. The hypothesis may be thought an arbitrary one: we can but see. I think it will be admitted that, supposing it turned out to be correct, we should have learnt something worth knowing about the difference between the medieval and the counter-reformation church, and something about the difference between pre- and post-reformation European society. If if did not turn out to be correct, we might nevertheless expect to pick up some useful knowledge about something which is scarcely a staple of current historical discourse, though it threatens to become so.
109 citations
TL;DR: In this paper, the development of the microbial flora on meat stored in vacuum-bags at 0-2° for up to 9 weeks was studied, and it was found that the initial contamination of the meat before vacuum-packaging was important; meat with a very low initial number had lower numbers of bacteria throughout storage for upto 9 weeks and steaks cut from such meat which had been stored always had 1-2 days' additional aerobic shelf life at 4°.
Abstract: The development of the microbial flora on meat stored in vacuum-bags at 0–2° for up to 9 weeks was studied. Although the proportion of lactic acid bacteria increased relative to the aerobic spoilage organisms, the numbers of the latter continued to increase throughout storage. The initial contamination of the meat before vacuum-packaging was important; meat with a very low initial number had lower numbers of bacteria throughout storage for up to 9 weeks and steaks cut from such meat which had been stored always had 1–2 days’ additional aerobic shelf life at 4°. Spoilage of these steaks was due either to slime formation and off-odour associated with high counts of presumptive Pseudomonas spp., or by discoloration and souring (lactic acid bacteria). Extract release volume and pH measurements performed on the vacuum-packaged primal joints were only of value in determining the onset of aerobic spoilage when large numbers of Gram negative organisms were present, whereas the titrimetric method of spoilage evaluation of the vacuum-packaged meat showed a correlation with spoilage due to lactic organisms.
106 citations
TL;DR: The discussion correlates the development of the tegument with the changes in environment and a mechanism of spine growth is proposed.
101 citations
TL;DR: Plasma diazepam levels were estimated by gas-liquid chromatography following a single 10 mg dose administered to a health adult female population by the oral and intramuscular routes, and were found to be closely correlated with the weight of the patient.
Abstract: Plasma diazepam levels were estimated by gas-liquid chromatography following a single 10 mg dose administered to a health adult female population by the oral and intramuscular routes. The highest levels were achieved following oral administration, reaching a peak at 60 minutes, although injection into the thigh resulted in a more rapid rise initially. Injection into this site produced higher levels than when the buttock was used. Injection by nurses into the latter site produced particularly low plasma levels over the 90-minute period of study. The plasma levels found at 90 minutes following the oral and thigh routes were found to be closely correlated with the weight of the patient.
97 citations
TL;DR: In this paper, absolute differential elastic cross sections have been measured for the scattering of electrons from atomic hydrogen over the electron energy range from 20 to 680 eV and over the angular range from 10 to 140 degrees.
Abstract: For pt.II see ibid., vol.8, no.10, p.1683 (1975). Absolute differential elastic cross sections have been measured for the scattering of electrons from atomic hydrogen over the electron energy range from 20 to 680 eV and over the angular range from 10 to 140 degrees. The experimental techniques and method are those associated with crossed electron and modulated atom beams with momentum analysis of the incident and scattered electrons. The measured relative angular distributions were made absolute within 11% by means of the following sequence of measurements, (i) a phaseshift analysis around the (1s2s2)2S resonance elastic scattering in helium, (ii) relative beam densities of helium and hydrogen beams and (iii) absolute calibration of all apparatus functions.
87 citations
TL;DR: In this article, the authors measured the shear stress distributions around the periphery of a channel of complex cross section using Preston tube and found that the presence of the interaction between a channel and its flood plain has significantly altered the values and distributions of boundary shear.
Abstract: Shear stress distributions were measured around the periphery of a channel of complex cross section using Preston tube. The complex section consists of a deep channel and a flood plain. The measurements were carried out in the laboratory for flow in the full cross section and when the flow was confined to the deep section. In this way it was possible to compare shear stress distributions under both isolated and interacting conditions. This has revealed that the presence of the interaction between a channel and its flood plain has significantly altered the values and distributions of boundary shear.
TL;DR: In this paper, the absolute differential cross sections for electrons losing 10.2 eV in exciting the n=2 states of atomic hydrogen have been measured over the angular range 20 to 140 degrees for incident electron energies of 54 to 680 eV.
Abstract: Absolute differential cross sections for electrons losing 10.2 eV in exciting the n=2 states of atomic hydrogen have been measured over the angular range 20 to 140 degrees for incident electron energies of 54 to 680 eV. The experimental apparatus, method and techniques are based upon those normally used in crossed electron and modulated atom beams experiments which study electron energy-loss spectra with good angular (2 degrees ) and energy (0.03 eV) resolution of the incident and scattered beams. Absolute cross section values have been determined by a method based on (i) a phase shift analysis of the elastic differential scattering of electrons from resonant states the (1s2s2)2S state in helium and the (3s23p54s2)2P3/2 and 2P1/2 states in argon and (ii) measurement of beam source pressures.
TL;DR: Analysis of association coefficients for the commonest species suggested that there are two distinct species groupings within the community of Fucus serratus L.'s serrated wrack.
TL;DR: A number of ways of using parallelism are distinguished, including disjoint processes, competition, cooperation, and communication, in each case an axiomatic proof rule is given.
TL;DR: In this article, uniaxial and rotating bending fatigue tests were carried out on polypropylene, polycarbonate, poly(methyl methacrylate) (PMMA), poly(tetramethylene terephthalate) (PTMT) and glass filled PTMT to establish the general regimes of thermal softening and fatigue types of failure observed in earlier tests on acetal copolymer.
TL;DR: The results indicate that phytochrome is not the photoreceptor pigment for this response, in spite of the similarity of the response in all other respects to the photoperiodic responses of flowering plants and other algae.
Abstract: The crustose phase of Scytosiphon lomentaria (Lyngb.) J. Ag. persists indefinitely in 16 h of white light per day, but produces erect, cylindrical thalli vegetatively in 8-h days. The critical daylength for this short-day (SD) response is sharply defined, and, between 12 and 13 h, differences in daylength of only 15 min produce substantial differences in response. A significant response to SD can be induced by as few as 4 SD cycles, but 10–12 cycles are required to saturate the response and induce more than 90% of the plants to form thalli. The response to SD is completely inhibited by a 1-min light-break with a low irradiance of blue light, given in the middle of a 16-h dark period, but is unaffected by longer periods and higher irradiances of red or far-red light. There is good reciprocity between the irradiance and the length of a light-break with blue light, and 50% inhibition of the response to SD is induced by about 2 nE cm-2 at 449 nm. All attempts to reverse the inhibitory effects of blue light by subsequent irradiation with another wavelength have so far failed. These results indicate that phytochrome is not the photoreceptor pigment for this response, in spite of the similarity of the response in all other respects to the photoperiodic responses of flowering plants and other algae.
TL;DR: This form of treatment, during operation, of intercostal nerve blocks with lignocaine and bupivacaine had no beneficial effects on lung function and is not recommended for the relief of pain following surgery.
Abstract: SUMMARY The use, during operation, of intercostal nerve blocks with lignocaine and bupivacaine for the relief of pain following thoracotomy was assessed in 138 patients. Irrespective of the method used to evaluate efficacy, it was not possible to demonstrate a lasting effect of clinical significance favouring either local anaesthetic agent. This form of treatment, although free from serious side effects, had no beneficial effects on lung function and is not recommended for the relief of pain following surgery.
TL;DR: The clinical, virological and pathological findings in 5 patients with neurological complications associated with rubella virus infection are described, including one patient who died and two who recovered completely from encephalitis and bilateral optic neuritis.
Abstract: The clinical, virological and pathological findings in 5 patients with neurological complications associated with rubella virus infection are described. The neurological illnesses began four to ten days after the rubella illnesses. The patients were all males aged between 6 and 17 years and were diagnosed during one non-epidemic year in a population of 1-5 million people. All the patients had rubella specific IgM in their sera. Two patients had no rash. In one of the patients who died, left internal carotid artery thrombosis and cerebral infarction were found at post-mortem. Rubella virus antigen and particles resembling rubella virus were found in the brain together with IgG and IgM in the same areas. This patient also had extensive liver necrosis. The other patient had a severe meningomyelitis and radiculitis and he recovered completely after two years. His serum rubella antibody rose significantly and was shown to leak into CSF during the acute stage of his illness. Three patients had a rash. Two of these patients had encephalitis: one recovered completely and the other had residual disability. The third patient had bilateral optic neuritis from which he recovered completely. Rubella specific IgM was, however, present in his serum for the abnormally long time of twenty-eight weeks indicating possible persistence of rubella virus.
TL;DR: It is suggested that the prefrontal cortex acts to limit the response to painful stimulation, and that this anti-nociceptive function is localised in or near the sulcal region.
Abstract: REPORTS indicate that responses to pain may be modified by damage to the frontal lobes (see refs 1 and 2). Nevertheless, neither the nature of the change nor the degree to which any effect of damage is localised anatomically has been firmly established. I have systematically examined the function of the prefrontal cortex in response to an aversive stimulus in the rat. Small quantities of a short-acting anaesthetic, procaine hydrochloride, were injected to block directly the neural function of specific areas within the prefrontal cortex. The prefrontal cortex in the rat occupies both a lateral region, the dorsal bank of the rhinal sulcus, and a medial region, the pregenual medial wall of the hemisphere3. In the rat, the prefrontal cortex is involved in brain-stimulation reward4. I suggest that, in addition, the prefrontal cortex acts to limit the response to painful stimulation, and that this anti-nociceptive function is localised in or near the sulcal region.
TL;DR: The main caeca, lined by Group III cells, appear to be more concerned with the movement of material back and forth within the lumen of the gut system, although they must also both secrete and absorb.
TL;DR: An in vitro preparation of gill segments of Mya arenaria was used to examine the kinetics of L - and D -alanine absorption and at least two pathways were concerned in the absorption of the L form only one of which is shared with the D form.
TL;DR: In this paper, absolute angular differential cross sections for the elastic scattering of electrons from atomic hydrogen have been measured for incident energies from 0.5 to 8.7 eV and for scattering angles between 10 and 150 degrees.
Abstract: For pt.I see ibid., vol.8, no.10, p.1641 (1975). Absolute angular differential cross sections for the elastic scattering of electrons from atomic hydrogen have been measured for incident energies from 0.5 to 8.7 eV and for scattering angles between 10 and 150 degrees. The experimental techniques and method were those normally used with crossed electron and modulated atom beams. The angular behaviour of the cross section is consistent with a partial-wave explanation; that is at the lowest energy of 0.5 eV, the angular distribution is peaked in the backward direction because of dominant p-wave exchange scattering; at 3.4 eV there is an angular minimum around 70 degrees because of interference between s, p and increasing d waves and at 8.7 eV the distribution is peaked in the forward direction because of the increasing effect of higher partial waves.
TL;DR: The antifungal metabolites produced by B. subtilis were found to be as inhibitory to many of the fungi commonly isolated from apple leaf scar tissue as they were to Nectria galligena.
Abstract: Apple rootstocks were sprayed after leaf fall with two antibiotic-yielding isolates of Bacillus subtilis Both could be recovered from the leaf scar tissue throughout the dormant season and spring, but with time an increasing number of strains of B subtilis were isolated, all of which possessed both antifungal and antibacterial activity similar to that of the original strains used B subtilis did not persist on the rootstock bark The antifungal metabolites produced by B subtilis were shown to be relatively stable compounds in vitro but the antibacterial metabolites were rapidly inactivated The antifungal metabolites were found to be as inhibitory to many of the fungi commonly isolated from apple leaf scar tissue as they were to Nectria galligena
TL;DR: In this paper, an X-ray/VUV streak camera with a time resolution of ≈20 psec was described, where the X-rays were obtained from a laser plasma, down to 22 psec half width separated by 42 psec.
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TL;DR: Some of the conceptual and methodological tools which are available for the solution of the problems of achieving data reliability, including the concept of type, direct product, union, sequence, recursion and mapping are outlined.
Abstract: This paper surveys the problems of achieving data reliability, and finds them more severe than those of program reliability. It then outlines some of the conceptual and methodological tools which are available for the solution of these problems, including the concept of type, direct product, union, sequence, recursion and mapping. It touches on the topdown design of data and programs, and argues that references or pointers are to be avoided. It concludes with an annotated bibliography for further reading.
TL;DR: An in vitro preparation of the gill of the common cockle was used to examine the absorption of neutral and basic amino acids from concentrations approximating to those in sea water, and l-Alanine was absorbed against the gradient by a carrier-mediated process, which was susceptible to metabolic inhibition, and competitive inhibition by l-methionine.
TL;DR: In this paper, a dynamic mathematical model for simulation of sedimentation in meandering streams is briefly described, which is composed of component mathematical models which are formulated to predict the following aspects of the system for a given physical situation and a single time increment.
Abstract: A dynamic mathematical model for simulation of sedimentation in meandering streams is briefly described. This is composed of component mathematical models which are formulated to predict the following aspects of the system for a given physical situation and a single time increment. (1) The characteristics of the plan form of the meander; (2) the movement of the meander in plan, and definition of cross-sections across the meander in which erosion and deposition are considered in detail; (3) the hydraulic properties of the channel in the bend and the erosional and depositional activity within the channel as defined in specific cross-sections; (4) the nature and occurrence of cut-off; (5) a relative measure of the discharge during a seasonal high water period, which is used in (3) and (4); (6) aggradation.
The model, in the form of a FORTRAN IV computer program, has been used to simulate various aspects of sedimentation in meandering streams by performing a set of experiments with the program under different input conditions.
The geometry of simulated point bar sediments, as controlled by channel migration over floodplains with variable sediment type, agrees broadly with the natural situation, however extensive sheets of point bar sediment cannot be simulated because large scale meander-belt movements are not accounted for.
In the simulated sediments, successive surfaces of the point bar before falling stage deposition (lateral and vertical) may be picked out, and these delineate the epsilon cross-stratification of Allen (1963b). The epsilon unit thickness is that measured from bankfull stage down to the lowest channel position existing prior to deposition.
The model records the characteristic fining upwards of grain sizes in the point bar, and the systematic distribution of sedimentary structures. Channel migration combined with seasonal scouring and filling across the channel section produces a characteristic relief in the basal scoured surfaces and facies boundaries (as defined by variation in grain size and sedimentary structure). A related lensing and inter-fingering of the facies may also be present. The model also records large-scale lateral changes in grain size and sedimentary structure associated with changes in the shape of developing meanders.
When channel migration is combined with a constant aggradation rate the model predicts a general slope (relative to the land surface) of facies boundaries and scoured basal surfaces upward in the direction of channel movement. If aggradation sufficiently increases the thickness of fine-grained overbank material, there is a channel stabilization effect. It is shown that a complete sequence of point bar sediments capped by overbank sediments would rarely be preserved in the moving-phase situation. Such preservation only becomes likely when an aggrading section lies out of range of an eroding channel for a considerably longer time span than it takes a meander to move one half-wavelength downvalley. Deep channel scours have a higher preservation potential than contemporary shallower ones.
Where appropriate field data exist the model can be used in the more accurate recognition of ancient fluviatile sediments. Inferences may be made about the erosion-deposition processes operating in the ancient channel system, and the geometry and hydraulics of the system can be alluded to. A representative application of the model to the quantitative interpretation of an ancient point bar deposit is illustrated. There is reasonable agreement between the natural and the simulated deposits, and a broad quantitative picture of the palaeoenvironment of sedimentation is obtained.
TL;DR: In this paper, the late-pleistocastic period in North-Easter Ireland is discussed. But the focus is not on the economic aspects of the region, but on the social aspects.
Abstract: (1975). THE LATE-PLEISTOCENE PERIOD IN NORTH-EASTERN IRELAND: AN ASSESSMENT 1975. Irish Geography: Vol. 8, No. 1, pp. 1-23.
TL;DR: The contracture normally induced in isolated bovine tracheal smooth muscle by potassium‐rich solution was abolished by removal of the extracellular calcium and returned when calcium was added to the solution in a concentration greater than 0·05 mmol/l.
Abstract: 1. The contracture normally induced in isolated bovine tracheal smooth muscle by potassium-rich solution was abolished by removal of the extracellular calcium. The contraction returned when calcium was added to the solution in a concentration greater than 0.05 mmol/l. 2. The amplitudes of the potassium-contracture, and of the contractile responses to histamine and acetylcholine in normal physiological solutions, declined at low temperatures (15-25 degrees C). If drugs were added during the plateau phase of the potassium contracture, the extra tension developed above the contracture did not change with temperature. 3. Calcium-depletion reduced the responses to drugs, and repeated application of the drugs in calcium-free solution produced progressively smaller contractions, suggesting that an intracellular store of calcium was being used up. 4. Depolarization of calcium-depleted tracheal muscle by high-K+ solution without calcium produced responses to drugs which were larger than those in sodium-based calcium-free solutions. There was no potentiation in a solution in which sodium was replaced by sucrose, suggesting that potassium was not acting simply by replacing the sodium. 5. It is suggested that depolarization of the membrane by potassium makes available a fraction of bound calcium which was not available in calcium-free sodium-based solution.
TL;DR: The antral pH dominates over duodenal pH as a factor in controlling gastrin release and atropine in doses which blocked acid release and produced marked cardiac effects failed to inhibit the release of gastrin from the antrum on vagal stimulation, suggesting that, using this model, vagal release of Gastrin, if cholinergic, is highly resistant toAtropine.
Abstract: The release of gastrin by direct electrical stimulation of the vagus was studied together with the relative effects on the response of antral and duodenal acidification. As expected, gastrin levels increased to three times the normal simulated response following antral neutralization. In contrast, duodenal acidification failed to influence the vagal release of gastrin when the antrum was neutralized although it had a minor effect when the antrum was acidified. Thus the antral pH dominates over duodenal pH as a factor in controlling gastrin release. Surprisingly, atropine in doses which blocked acid release and produced marked cardiac effects failed to inhibit the release of gastrin from the antrum on vagal stimulation. This suggests that, using this model, vagal release of gastrin, if cholinergic, is highly resistant to atropine.