Showing papers by "University College Dublin published in 1970"
TL;DR: In this paper, the Fubini-Furlan-Rossetti theorem is rederived in a simple way by using the PCAC hypothesis extended in a minimal way so as to take into account the electromagnetic interactions up to the first order in e.g.
109 citations
TL;DR: The Braun-Blanquet method is considered to combine several advantages of the other methods and to be most economical in terms of the ratio of time input to information emerging as mentioned in this paper.
Abstract: In three areas of vegetation (dune, mountain heath and salt marsh) the following phytosociological techniques have been tested and compared, using the same data: the Braun-Blanquet method; association and inverse analysis ofWilliams L cluster analysis (agglomerative classification) based on different coefficients of similarity; and ordination (principal components analysis performed on matrices of different coefficients). The Braun-Blanquet method is considered to combine several advantages of the other methods and to be most economical in terms of “efficiency” (ratio of time input to information emerging).
73 citations
TL;DR: The mean lifetime of the 3ΛH hypernucleus has been estimated in nuclear emulsion using the (π−+1H+2H) decays both at rest and in flight as discussed by the authors.
47 citations
TL;DR: Ova containing pronuclei as well as apparently normal cleaved ova were recovered following in vivo fertilization attempts in the ewe, and growth medium proved superior in terms of final maturation.
Abstract: Maturation studies were carried out on 241 cattle oocytes. Media used were bovine follicular fluid and growth medium. Both media supported a resumption of meiosis in ca. 80 % of cases, but growth medium proved superior in terms of final maturation.Fertilization attempts were carried out on 564 oocytes following culture (27–32 h) in growth medium. In vitro fertilization attempts (107 oocytes) and in vivo fertilization attempts (82 oocytes) in the rabbit yielded negative results. Following in vivo fertilization attempts in the ewe, ova containing pronuclei as well as apparently normal cleaved ova were recovered.
42 citations
39 citations
TL;DR: In this paper, a new type of isomerism was reported for a wide variety of transition metal carbonyl complexes of the general type (π-Ring)M(CO)(L)X where L is a tertiary phosphine or phosphite ligand.
32 citations
TL;DR: In this article, it is shown that the particle temperature will usually exceed the gas temperature because of the surface recombination, and equilibrium temperatures are obtained by equating the recombination heat to the surface heat.
Abstract: Observation of small particles in positive columns shows that considerable interaction can occur between them and the plasma. This paper suggests methods for analysing the complex situations which may arise and discusses some simplified cases, illustrated by reference to discharges in argon at about 1 torr. Ordinary positive column theory can be modified to allow for presence of cold particles by treating them as distributed insulated negative surface ionization sinks, additional to the wall sink if their effect is relatively small, and replacing it if their effect is large. Increases in electron temperature and axial field result and the radial electron concentration pattern may be altered, an off-centre maximum developing under some conditions if the particles are concentrated near the axis. Dust-laden discharges may be noisy. The particle temperature will usually exceed the gas temperature because of the surface recombination. Equilibrium temperatures are obtained by equating the recombination heat to ...
32 citations
TL;DR: In this article, a comparison of the kinetics of substitution by phosphite ligands of cyclopentadienyl iron and ruthenium carbonyl halides is reported and in all cases a dissociative mechanism indicated.
30 citations
TL;DR: Preliminary observations have been carried out to look for radio signals associated with gravitational waves, and although inconclusive, the observations suggest the value of pressing on with further experiments.
Abstract: Preliminary observations have been carried out to look for radio signals associated with gravitational waves. Although inconclusive, the observations from five receivers in the British Isles suggest the value of pressing on with further experiments.
29 citations
TL;DR: In this article, the existence of particle-unstable states of the Λ12C and Λ14N hypernuclei produced by the absorption at rest of K− mesons in light emulsion nuclei was shown.
29 citations
01 Apr 1970
TL;DR: In this paper, a theory of cascade synthesis is presented in which the basic zero-producing sections (C, D and Brune) are extracted in a unified manner without recourse to nonreciprocal or nonphysical sections.
Abstract: A theory of cascade synthesis is presented in which the basic zero-producing sections (C, D and Brune) are extracted in a unified manner without recourse to nonreciprocal or nonphysical sections. The element values of the various sections are given explicitly in terms of the extracted zeros of transmission, the value of the impedance function and its derivative at the extracted zero.
TL;DR: The last glacial deposits of the Ballaugh-Kirkmichael area in the north-east of the Isle of Man have been investigated by analysis of pollen and macroscopic fossils and by radiocarbon dating.
Abstract: The last glacial deposits of the Ballaugh-Kirkmichael area in the north-east of the Isle of Man have been investigated by analysis of pollen and macroscopic fossils and by radiocarbon dating. Assemblages totalling over 160 taxa of vascular plants and mosses have been recorded from strata referred to LateWeichselian zones I, II and III. Among the most noteworthy species are 46 not now living on the island; these include Dianthus deltoides, Juncus balticus, Lychnis viscaria, Ranunculus hyperboreus, Sibbaldia procumbens, Meesia tristicha, Helodium blandowii and Polytrichum norvegicum. The vegetation comprised a great diversity of communities of open, largely calcareous grassland, snow beds, mires both base-rich and base-poor, flushes, freshwater, inundated flats and calcareous dunes. Saline conditions are indicated by Glaux maritima and Triglochin maritima . Trees were represented only by Betula and the taller shrubs by Juniperus and Salix .
TL;DR: In this paper, a sample of hypernuclei decaying non-mesonically with the emission of one or two charged particles which were obtained from K− meson captures at rest in nuclear emulsion was reported.
TL;DR: It was concluded that voluntary straw intake was limited, at the lowest level of supplementaryprotein, by a deficiency of absorbed protein, and at the higher levels of supplementary protein, intake was probably limited by the capacity of the alimentary tract.
Abstract: 1. Daily allowances of 1·37 kg of concentrates, containing either 8·9 (treatment A), 13·6 (B), 19·1 (C) or 29·2% crude protein (D) were given to 40 individually-fed steers eating long barley straw to appetite over a 112-day winter feeding period. Voluntary straw intake on treatment B was 25% higher than that on treatment A. There were no signiicant differences in straw intake between treat-ments B, C, and D. Mean daily live-weight gains (kg) for the treatment groups were A, −0·22; B, 0·05; C, 0·04; D, 0·15. When the animals were turned out to pastore, group A showed very rapid compensatory growth, and it was concluded that this was mainly due to differences between the groups in their changes in alimentary tract contents. Vitamin A and D supplementation did not affect straw intake or performance.2. When the above supplements were given to steers in metabolism crates receiving barley straw in restricted or unrestricted quantities, it was found that an increase in the crude-protein content of the supplement significantly increased the digestibility of the organic matter, crude fibre and crude protein of the whole diet when straw intake was restricted, and significantly increased the digestibility of crude fibre and crude protein when straw was unrestricted.3. It was concluded that voluntary straw intake was limited, at the lowest level of supplementary protein, by a deficiency of absorbed protein. At the higher levels of supplementary protein, intake was probably limited by the capacity of the alimentary tract.
TL;DR: In this paper, the complex effects of dust in positive columns, with special reference to plasma parameters, dust temperature, and distribution and movement of the dust, were considered for analysis.
TL;DR: Pseudouridine excretion has been measured in a group of patients with chronic lymphatic leukaemia using a modification of methods so far described, and suggests an increased turnover of t-RNA in these patients, but the reason for this is not known at present.
Abstract: Pseudouridine excretion has been measured in a group of patients with chronic lymphatic leukaemia using a modification of methods so far described. All had elevated levels initially, which returned to normal after treatment, though there was a transient rise in levels as the white cell count reduced. This suggests an increased turnover of t-RNA in these patients, but the reason for this is not known at present.
TL;DR: Evidence of normal development of cattle ova following storage at 10 °C is obtained and of thirty-two treated ova transferred to the oviducts of pseudo-pregnant rabbits, twenty-three were recovered and ten had undergone further cleavage.
Abstract: We have obtained evidence of normal development of cattle ova following storage at 10 °C. Of thirty-two treated ova transferred to the oviducts of pseudo-pregnant rabbits, twenty-three were recovered and ten of these had undergone further cleavage.
TL;DR: Bromination and chlorination of phloroacetophenones in acetic anhydride resulted in deacylation with the formation of halophloroglucinol derivatives.
TL;DR: It is concluded that the metabolic derangements occurring in association with acromegaly result in Schwann cell abnormalities, and repeated episodes of segmental demyelination may then predispose to eventual connective tissue hypertrophy.
Abstract: The pathologic features observed in a sural nerve biopsy from a subject with acromegalic peripheral neuropathy are presented. Examination of individually teased nerve fibers revealed diffuse segmental demyelination. Since each internodal segment represents the territory occupied by a single Schwann cell, the presence of the segmental loss of myelin indicates dysfunction throughout the Schwann cell system. It is concluded that the metabolic derangements occurring in association with acromegaly result in Schwann cell abnormalities. Repeated episodes of segmental demyelination may then predispose to eventual connective tissue hypertrophy.
01 Jan 1970
TL;DR: In deciding on the most suitable method to use in a survey of Irish vegetation, the Braun-Blanquet method was compared with a number of other methods using the same field data.
Abstract: In deciding on the most suitable method to use in a survey of Irish vegetation, the Braun-Blanquet method was compared with a number of other methods using the same field data.1 The Braun-Blanquet method is basically a polythetic, sub-divisive method of classification: a set of releves is divided into two sub-sets depending on the presence or absence of a group of differential species and this process is continued until the eventual sub-sets have an acceptable level of uniformity in their floristic composition. Cluster analysis, developed mainly by numerical taxonomists (Sokal & Sneath 1963) is a polythetic, agglomerative classification, whereby the releves are grouped on the basis of their overall similarity, and each of these groups are in their turn fused until the whole set of releves is accounted for.
TL;DR: Three possible isomeric 3-hydroxy-β-chloroflavindogenide chlorohydrins have been prepared by the action of hydrogen chloride in benzene-ether on flavindogenides epoxides as mentioned in this paper.
01 Feb 1970
TL;DR: In this article, the advantage of combining a current-controlled chopper regulator, using digital techniques, with a laminated-field series motor is outlined, design criteria are suggested, and an experimental system is described.
Abstract: The thyristor controller and the d.c. motor of a battery-electric vehicle are considered as a system. The advantage of combining a current-controlled chopper regulator, using digital techniques, with a laminated-field series motor is outlined, design criteria are suggested, and an experimental system is described. Performance measurements using specially developed wattmeters are presented, which show the division of losses in the system, and the exceptionally high overall efficiencies over the speed range.
TL;DR: In this article, an apparent variation of the mass of the Λ-hyperon with the energy of the decay π−-meson has been observed in emulsion, which is attributed to a systematic error in the range-energy relation for emulsion for particle velocities greater than 0.6c.
Abstract: An apparent variation of the mass of the Λ-hyperon with the energy of the decay π−-meson has been observed in emulsion. This anomaly has been attributed to a systematic error in the range-energy relation for emulsion for particle velocities greater than 0.6c.
TL;DR: Dietary intake was related to living conditions, the subjects living with relatives having the best intake, and those living alone and dependent on Meals on Wheels having the lowest intake.
Abstract: A DIETARY survey was carried out between October and December, 1969, on thirty-one elderly healthy subjects aged 64 to 86 years living in central Dublin. Their living conditions in relation to age, sex and social contacts, and in relation to dietary intake were analysed. Eighty-seven per cent lived alone but contact with church, family and friends provided social contact to varying degrees. Just over half the subjects depended on day clubs or Meals on Wheels for supplementary dietary intake. The average dietary intake of the sample was generally adequate, but was below the recommended British Standards for Calories and Calcium. However 36% of the subjects had an intake of Vitamin C, and 6% had an intake of iron, below the recommended British Standards. The intake of nutrients diminished with increasing age. Dietary intake was related to living conditions, the subjects living with relatives having the best intake, and those living alone and dependent on Meals on Wheels having the lowest intake.
TL;DR: These results, based on balloon-borne spark chamber observations, would, if confirmed, be of great significance not only for the Crab pulsar but also for the field of gamma ray astronomy as a whole, where the evidence for point sources of gamma rays remains marginal.
Abstract: VASSEUR et al.1 have recently presented results which, they suggest, appear to show that the Crab pulsar NP 0531 + 21 emits a flux of ∼ 10−5 photons cm−2 s−1 at a photon energy >50 MeV. Their results, based on balloon-borne spark chamber observations, would, if confirmed, be of great significance not only for the Crab pulsar but also for the field of gamma ray astronomy as a whole, where the evidence for point sources of gamma rays remains marginal2. We feel, however, that the statistical weight of the data in the report is much weaker than the authors suggest.
TL;DR: Untersuchungen der Pigmenteigenschaften des PilzesEpicoccum nigrum ergaben die Anwesenheit einer flavipinartigen Substanz (3, 4, 5-trihydroxy-6-Methylphthal-Aldehyd).
Abstract: Untersuchungen der Pigmenteigenschaften des PilzesEpicoccum nigrum ergaben die Anwesenheit einer flavipinartigen Substanz (3, 4, 5-trihydroxy-6-Methylphthal-Aldehyd).
TL;DR: The normal acid urinary reaction of dogs together with their inability to acetylate sulphonamides may largely contribute to the longer persistence of these compounds in dogs as compared with other species of domestic animals.