Showing papers by "University College Dublin published in 1981"
TL;DR: In this paper, the self-thinning rule is reformulated and an alternative allometric derivation is presented, based on the traditional power equation w = Kρ−a, where a is 3 2.
314 citations
TL;DR: The literature on corticosteroid binding globulin (transcortin) in the human is reviewed under the following headings: physicochemical properties, biosynthesis, measurement, and physiological, pharmacological and pathological variations with particular emphasis of the effects of pregnancy and oral contraceptives.
Abstract: The literature on corticosteroid binding globulin (transcortin) in the human is reviewed under the following headings: physicochemical properties, biosynthesis, measurement, and physiological, pharmacological and pathological variations with particular emphasis of the effects of pregnancy and oral contraceptives. Finally, the physiological implications of corticosteroid binding globulin are discussed.
197 citations
TL;DR: This paper tackles the problem of how one might select further search terms, using relevance feedback, given the search terms in the query, by generating a number of different spanning trees from a variety of association measures.
Abstract: This paper tackles the problem of how one might select further search terms, using relevance feedback, given the search terms in the query. These search terms are extracted from a maximum spanning tree connecting all the terms in the index term vocabulary. A number of different spanning trees are generated from a variety of association measures. The retrieval effectiveness for the different spanning trees is shown to be approximately the same. Effectiveness is measured in terms of precision and recall, and the retrieval tests are done on three different test collections.
143 citations
TL;DR: In this paper, the authors studied the spectra of laser-produced plasmas in the grazing-incidence region from 40 to 200 A. The spectra are characterized by strong regions of resonancelike emission extending typically over 9 −18 eV.
Abstract: Using targets containing compounds of the elements cesium through lutetium, we studied the spectra of laser-produced plasmas in the grazing-incidence region from 40 to 200 A. The spectra are characterized by strong regions of resonancelike emission extending typically over 9–18 eV. With increasing Z, the spectra show certain systematic variations in character and move monotonically toward shorter wavelengths. From a collisional-radiative plasma model, the ion stages responsible for the emission are identified as viii through xvi. The resonances are attributed to 4d–4f transitions that, because Δn = 0, tend to overlap for different ion stages of the same element.
134 citations
TL;DR: Ro 15-1788 has been shown by psychometric evaluation to antagonise the central benzodiazepine effects of Ro 11-3128 (3-methylclonazepam) in healthy male volunteers when both compounds were given orally as single doses.
114 citations
TL;DR: In this article, the authors present an overview of the essential features of the laser systems used to generate such plasmas followed by a summary of some concepts in plasma physics necessary for their proper interpretation, and the theory of the evolution of the plasma is presented in terms of a hydrodynamic model and the relationship between laser irradiance and plasma temperature is discussed.
Abstract: When the output of a typical Q-switched laser is focused onto a solid target, a short-lived, localized plasma, characterized by very high ion and electron densities and by very high temperatures, is formed. The present article begins with an outline of the essential features of the laser systems used to generate such plasmas followed by a summary of some concepts in plasma physics necessary for their proper interpretation. The theory of the evolution of the plasma is presented in terms of a hydrodynamic model and the relationship between laser irradiance and plasma temperature is discussed. Several of the more important methods used for studying plasma properties, including inter-ferometry, mass-spectrometry and optical and X-ray spectroscopy, are described and the results for some typical plasmas are presented.
76 citations
TL;DR: The fatty acids did not alter the duration or type of the induced arrhythmia and antagonized the potentiating effect of the long‐chained saturated and mono‐unsaturated acids on the hypoxia in lowering the VAT.
Abstract: 1 The ventricular arrhythmia threshold (VAT) was measured in the isolated Ringer-perfused rabbit heart (Langendorff preparation) by applying a single 10 ms square-wave pulse of current to the left ventricle during the vulnerable period of the late systole under normoxic and hypoxic conditions. 2 The sodium salt of the fatty acid was bound to albumen and incorporated in the Krebs-Henseleit solution which was maintained at 37 degrees C and gassed with 95% O2 and 5% CO2 (normoxia) or 5% CO2 in air (hypoxia). 3 Saturated fatty acids failed to alter the VAT under normoxia. 4 Naturally occurring long-chained saturated and mono-unsaturated fatty acids with chain lengths varying from 14 to 20 carbons, but not the 12 carbon lauric acid, potentiated the effect of the hypoxia in lowering the VAT. 5 Short-chained 8 and 10 carbon saturated and long-chained polyunsaturated fatty acids antagonized the effect of hypoxia on the VAT. 6 In addition the polyunsaturated acids antagonized the potentiating effect of the long-chained saturated and mono-unsaturated acids on the hypoxia in lowering the VAT. 7 The fatty acids did not alter the duration or type of the induced arrhythmia.
72 citations
TL;DR: The main conclusion is that serious injury to the forecoming head at birth is almost invariably a direct effect of forceps.
72 citations
31 May 1981
62 citations
TL;DR: In this paper, the authors discussed the implications for determining the photon contribution to the highest-energy cosmic rays, and proposed a method to calculate the contribution of a photon to a cosmic ray.
Abstract: Cosmic-ray photons of energy g5 \ifmmode\times\else\texttimes\fi{} ${10}^{19}$ eV will pair produce in the Earth's magnetic field. The electrons radiate by quantum synchrotron radiation; the produced photons may in turn pair produce and continue the cascade. This electromagnetic cascade interacts with the Earth's atmosphere and produces an extensive air shower. Some implications for determining the photon contribution to the highest-energy cosmic rays are discussed.
58 citations
TL;DR: The response of the adenylate cyclase to stimulation by Ca2+ within the membrane is a transient increase in activity followed by a period of 'down regulation', which occurs by a Ca2-dependent mechanism.
Abstract: 1. The adenylate cyclase of bloodstream forms of Trypanosoma brucei is regulated by Ca2+. 2. The Ca2+-stimulated activity is not inhibited by trifluperazine, tentatively suggesting that the stimulation may not be mediated by calmodulin. 3. The Ca2+-binding site of the receptor regulating the adenylate cyclase is buried within the hydrophobic region of the plasma membrane and is not exposed to either the inner or the outer aqueous-phase bounding the membrane in unstimulated cells. 4. The response of the adenylate cyclase to stimulation by Ca2+ within the membrane is a transient increase in activity followed by a period of 'down regulation'. 5. The 'down regulation' of the adenylate cyclase also occurs by a Ca2+-dependent mechanism.
TL;DR: In this paper, it was shown that if k is a finite field of even characteristic, each element of the symplectic group or of the two nonisomorphic orthogonal groups is conjugate to its inverse, and thus the complex characters of these three families of finite groups are all real-valued.
TL;DR: In this article, the authors report results from a nationwide study, based on a representative sample in the Republic of Ireland, which is part of a harmonised study of subjective social indicators which has been carried out in eight member countries of the European Community.
Abstract: The present paper reports results from a nationwide study, based on a representative sample in the Republic of Ireland It is part of a harmonised study of subjective social indicators which has been carried out in eight member countries of the European Community The data, which were obtained by survey techniques, are largely subjective or perceptual in nature However, objective data were also obtained, thus permitting direct comparisons, in many cases, between objective conditions and subjective measures related to housing and neighbourhood to determine which characteristics were most highly predictive of overall satisfaction with housing and overall satisfaction with neighbourhood In addition, the relationships between housing and neighbourhood variables and more global attitudinal variables (ie, life satisfaction and anomia) were explored
TL;DR: In this article, the amplitude equations that govern the motion of wavetrains near the critical point of unstable dispersive, weakly nonlinear physical systems are considered on slow time and space scales.
Abstract: The amplitude equations that govern the motion of wavetrains near the critical point of unstable dispersive, weakly nonlinear physical systems are considered on slow time and space scales T m ═ e m t ; X m ═ e m x ( m ═ 1, 2,...). Such systems arise when the dispersion relation for the harmonic wavetrain is purely real and complex conjugate roots appear when a control parameter ( μ ) is varied. At the critical point, when the critical wavevector k c is non-zero, a general result for this general class of unstable systems is that the typical amplitude equations are either of the form ( ∂/∂ T 1 + c 1 ∂/∂ X 1 ) (∂/∂ T 1 + c 2 ∂/∂ X 1 ) A ═ ±α A ─ β AB , ( ∂/∂ T 1 + c 2 ∂/∂ X 1 ) B ═ (∂/∂ T 1 + c 1 ∂/∂ X 1 ) | A | 2 , or of the form ( ∂/∂ T 1 + c 1 ∂/∂ X 1 ) (∂/∂ T 1 + c 2 ∂/∂ X 1 ) A ═ ±α A - β A | A | 2 . The equations with the AB -nonlinearity govern for example the two-layer model for baroclinic instability and self-induced transparency (s. i. t.) in ultra-short optical pulse propagation in laser physics. The second equation occurs for the two-layer Kelvin-Helmholtz instability and a problem in the buckling of elastic shells. This second type of equation has been considered in detail by Weissman. The AB -equations are particularly important in that they are integrable by the inverse scattering transform and have a variety of multi-soliton solutions. They are also reducible to the sine-Gordon equation ϕ ξƬ ═ ± sin ϕ when A is real. We prove some general results for this type of instability and discuss briefly their applications to various other examples such as the two-stream instability. Examples in which dissipation is the dominant mechanism of the instability are also briefly considered. In contrast to the dispersive type which operates on the T 1 -time scale, this type operates on the T 2 -scale.
TL;DR: It was seen that it will be necessary to ensure a pure water supply, a good road system, educational and economic development, as well as more comprehensive health care coverage, if the general health status of rural dwellers in this region is to be raised.
TL;DR: The number of SCE per cell does not differ significantly between sexes, but differs with age, and people in the age bracket 30–40 years have a higher number than others, while age seems to affect both sexes equally.
Abstract: After analysing the distribution of the numbers of sister chromatid exchanges (SCE) in 200 cells from one individual, we found no evidence to reject the hypothesis of a normal distribution (P>0.50). We then compared the mean numbers of SCE per cell in 18 individuals, three males and three females of each of three age groups (0–10, 30–40, and 60–70 years of age) by means of a one-way analysis of variance, and found that there was no significant difference among them at the level of 5%. When these data were analysed by means of a two-way analysis of variance to test separately the effect of sex and age, we found that the number of SCE per cell does not differ significantly between sexes, but differs with age (P>0.05). People in the age bracket 30–40 years have a higher number of SCE per cell. Age seems to affect both sexes equally.
TL;DR: In this paper, the authors used the atmospheric Cerenkov technique to detect γ rays from the direction of the X-ray source Cyg X-3, and observed rays of energy 1012eV.
Abstract: The Crimean Observatory group have detected γ rays from the direction of the X-ray source Cyg X-3 (refs 1–5): rays of energy 1012eV were observed using the atmospheric Cerenkov technique. Measurements with satellite-borne instruments in the 108eV region have shown effects from Cyg X-3 in one case6, but not in another7. Similarly, γ rays have been seen in some balloon flights8, but not in those of McKechnie et al.9 nor of White et al.10. A study using the atmospheric Cerenkov technique at 1011eV showed no effect11, though it has been shown to be compatible with the Crimean result4. We report here observations taken at Mount Hopkins Observatory, Arizona (altitude 2.3 km) in April, May and June 1980 using a similar system to that of Stepanian et al.3, which seem to confirm, at least qualitatively, the Crimean results.
TL;DR: In this article, the authors provide an anthology of results on the subject of models (chance mechanisms) that give rise to the Univariate Generalized Waring Distribution (UGD).
Abstract: The intent of this paper is to provide an anthology of results on the subject of models (chance mechanisms) that give rise to the Univariate Generalized Waring Distribution. These include results that have appeared in the statistical literature before as well as some new ones that appear for the first time in this paper. Some characterization problems relating to certain genesis schemes are also considered.
TL;DR: In this article, a general analysis of the statistics of a random network of threefold vertices is presented and it is demonstrated that Aboav's empirical formula for the number of sides mn on the neighbors of n-sided cells in a polycrystal is consistent with the conjecture that the cells are arranged randomly.
TL;DR: Cyperus longus L., which has a widespread but disjunct distribution throughout Europe and extends northwards into Britain, was found to be a C4 species based upon its Kranz leaf anatomy, low CO2 compensation point and the labelling of malate as an early product of 14CO2 fixation.
Abstract: .Cyperus longus L., which has a widespread but disjunct distribution throughout Europe and extends northwards into Britain, was found to be a C4 species based upon its Kranz leaf anatomy, low CO2 compensation point and the labelling of malate as an early product of 14CO2 fixation. The photosynthetic characteristics of C. longus are similar to many other C4 species with a high maximum rate of photosynthesis (> 1.5 mg CO2 m −2 s −1) and a relatively high temperature optimum (30–35°C), but unlike many C4 species the rate of photosynthesis does not decline rapidly below the optimum temperature and a substantial rate (0.6 mgCO2 m−2s−1)occursat 15°C. Leaf extension is very slow at 15°C and shows a curvilinear response to temperatures between 15 and 25°C. Leaves extend at a rate of almost 4 cm d−1 at 25°C.
Journal Article•
TL;DR: In this paper, the control and induction of ovulation in cattle are discussed with particular reference to use of progesterone-impregnated coils in heifers and beef cows.
Abstract: The control and induction of ovulation in cattle are discussed with particular reference to use of progesterone-impregnated coils in heifers and beef cows. Progesterone treatment for 14 days was required to obtain precise onset of oestrus. With 7, 9 or 12 days of progesterone treatment a luteolytic agent in the form of a prostaglandin (PG) or oestradiol benzoate had to be used. Fertility was normal after treatment durations of 7, 9 or 12 days, but fertility after 14-day treatment requires further testing. The progesterone coil was not effective in maintaining luteal-phase levels of progesterone throughout a 12-day treatment and increasing the concentration of progesterone in the coil from 4 to 20% was not effective in elevating the progesterone concentrations in blood. When progesterone concentrations dropped below approximately 1.5 ng/ml the basal level of LH began to rise before removal of the coil. A 2-fold rise in the basal level of LH was observed following the removal of the progesterone coil. This early rise in LH was absent in cows which did not ovulate after they were given a 12-day progesterone treatment and GnRH 24-36 h after removal of coils to induce the main LH peak. Absence of this early rise suggests that frequency and amplitude of episodic LH release were inadequate in the post-partum anovulatory period. Ovariectomy in the early post-partum period was not followed by an abrupt LH release.
TL;DR: A theoretical study of aggregrate structures involving alkaline-earth ions and cation vacancies has been carried out using computer simulation and techniques based on generalized Mott-Littleton methods as mentioned in this paper.
Abstract: A theoretical study of aggregrate structures involving alkaline-earth ions and cation vacancies has been carried out using computer simulation and techniques based on generalized Mott-Littleton methods. Accurate two-body interionic potentials, based on a simple shell model, have been used in the defect calculations. Mechanisms for the clustering of both nearest neighbour and next-nearest neighbour impurity-vacancy dipoles are considered and the relative importance of alternative pathways is deduced from the results. An investigation of the energetics of dopant ion precipitation in these systems is carried out by calculating the lattice energy of the metastable Suzuki phase. Our study shows that there are two aggregation pathways-one leading to the precipitation of the Suzuki phase, and the second resulting in the formation of a stable dopant trimer. The nature of the pathway adopted depends strongly on the radius of the dopant ion. Our results suggest simple interpretations of the kinetics of dip...
TL;DR: It is hoped that the models presented will clarify the importance or otherwise of climate to tick development and explore the potential of formulating a successful prediction system for tick activity, which should aid control of tick-transmitted diseases.
TL;DR: In this article, it is suggested that the soil smectite is a weathering product of the trio-ctahedral smectites inherited from the weathered basalt.
Abstract: The sand and silt fractions of soils derived from Tertiary basalt in northeastern Ireland exhibit unusually high cation-exchange capacities. Smectite was identified by X-ray powder diffraction in all size fractions and was selectively dissolved by treatment with 1 N HCl and 0.5 N NaOH. Structural formulae, based on chemical analysis of the dissolved material, suggest that the smectite is intermediate in composition between a di- and a trioctahedral mineral and that the octahedral cation occupancy, together with the numbers of Mg and Fe atoms per unit cell, decreases with decrease in particle size of the soil fraction examined. The mean formula for the smectite in the clay separates is: M+0.40(Si3.33Al0.67)(Al1.07Fe2+0.09 Fe3+0.41Mg0.82)O10(OH)2. Similar analysis of smectite present in clay-size material separated from weathered basalt rock taken from the bases of the soil profiles showed that it had close to the full trioctahedral occupancy. It is suggested that the soil smectite is a weathering product of the trioctahedral smectite inherited from the weathered basalt.
TL;DR: The potassium‐sparing diuretics, triamterene and amiloride, reduced urinary magnesium excretion in conscious saline‐loaded rats and urinary magnesium‐conservation was also detected when amILoride was used in combination with the potent ‘loop‐blocking' diuretic, frusemide.
Abstract: 1 The potassium-sparing diuretics, triamterene and amiloride, reduced urinary magnesium excretion in conscious saline-loaded rats. 2 Urinary magnesium-conservation was also detected when amiloride was used in combination with the potent 'loop-blocking' diuretic, frusemide.
TL;DR: In this article, a mire of some 23 ha, harbours plant communities representative of the more important stages in hydroseral succession, which are described, classified and mapped according to Ziurich-Montpellier methodology.
Abstract: Scragh Bog, a mire of some 23 ha, harbours plant communities representative of the more important stages in hydroseral succession. These communities are described, classified and mapped according to Ziurich-Montpellier methodology. Fen communities constitute the major part of the vegetation cover and that dominated by Schoenus nigricans forms the basis of a new subassociation within the Cirsio-Schoenetum nigricantis Br.-Bl. et Tx. 1952. Other new syntaxa proposed are the Erico-Sphagnetum plumulosi, the Carici limosae-Sphagnetum contorti and the Salici-Betuletum pubescentis pyroletosum. Environmental conditions, as assessed by water table, pH and Kcorr measurements and mineral analyses of surface waters, are considered in relation to the vegetation cover. Mineral analyses were performed on Sphagnum plumulosum and other bryophyte species which are important as initiators of the climax raised bog community. Growth measurements were also performed on S. plumulosum. The significance of the vegetation cover as well as the factors influencing the future rate of succession are discussed.
TL;DR: In this article, it was shown that a noncommutative simple algebra generated over a field F by two idempotents is necessarily the ring of 2×2 matrices over a simple extension of F.
TL;DR: Horseradish peroxidase has been conjugated with human immunoglobulin containing antibody to hepatitis B e antigen (anti-HBe) and this was used in a solid-phase 'sandwich' enzyme-linked immunosorbent assay designed for reading by eye, to test sera for HBeAg and anti-H be.
TL;DR: A compact versatile light source for producing VUV radiation from laser produced plasmas is described and a comparison is made with analogous results obtained using a ruby laser.
Abstract: A compact versatile light source for producing VUV radiation from laser produced plasmas is described Measurements of the spectral irradiance from CO(2) laser-produced plasmas on targets of gadolinium and ytterbium in the 115-220-nm range are given, and a comparison is made with analogous results obtained using a ruby laser