Showing papers by "University College Cork published in 1977"

Upper and lower Fredholm spectra II

Abstract: Joint upper and lower Fredholm spectra are defined for «-tuples of bounded linear operators, and the upper Fredholm spectrum is represen- ted both as the simultaneous eigenvalues and as the simultaneous approxi- mate eigenvalues of an /i-tuple of operators obtained by a Berberian-Quigley construction. Introduction. A bounded linear operator T: X -> Y between Banach spaces is said to be upper Fredholm if it has finite dimensional null space (T~x0) and closed range T(X), and is said to be lower Fredholm if its range T(X) is closed and has finite codimension. / is Fredholm iff it is upper and lower Fredholm. In this note we show that T is upper Fredholm iff a related operator P(T): <$(Y) is bounded below, where 9(X) is obtained as a certain quotient of the space lx(X) of all bounded A'-valued sequences. It is then shown that T is Fredholm iff P(T) is invertible. This construction is obtained in §1, the basic two theorems are established in §2, some immediate consequences in §3, and some consequences for joint upper and lower Fredholm spectra are obtained in §4. I. If X is a complex Banach space then let lx(X) denote the Banach space obtained from the space of all bounded sequences x = (xn) in X by imposing term-by-term linear combination and the supremum norm \\x\\ = supn||.xB||.

Effect of four herbicides and two oils on leaf-cell membrane permeability*†

Abstract: Summary: Leakage of electrolytes from leaf discs of treated Phaseolus Vulgaris L. plants was the main criterion used to study the effect of several chemicals on the permeability of leaf-cell membranes. Paraquat, diquat, dinoseb and oxyfluorfen (2-chloro-1-(3-ethoxy-4-nitrophenoxy)-4-(Trifluoromethyl) benzene) increased leaf-cell membrane permeability after exposure for 12 h or less. An‘aromatic’oil caused a large increase in permeability at 2–5 min after treatment. Increases in electrolyte release were also correlated with release of soluble amino acids from the leaf discs but the former method was the more sensitive. Increase in cell membrane permeability was always associated with injury symptoms such as appearance of necrotic areas in leaves. Chlorpropham, linuron, sodium azide, glyphosate and 2,4-D at 10−3M, as well as 1% X-77 surfactant and a non-phytotoxic isoparaffinic oil did not alter leaf-cell permeability at 12 h after treatment. Light was necessary for paraquat and oxyfluorfen to alter leaf cell permeability. Paraquat and oxyfluorfen caused a greater increase in leaf-cell permeability of a soybean mutant with yellow leaves as compared with the normal green leaves. With oxyfluorfen this difference in permeability was greater than with paraquat, and was associated with the appearance of severe necrotic injury symptoms in the yellow mutant; paraquat caused no injury symptoms. Resume: Effet de quatre herbicides et de deux huiles sur la permeabilite des membranes des cellutes foliaires La perte d'electrolytes a partir de disques foliaires de Phaseolus vulgaris L. ete le critere principal utilise pour etudier l'effet de plusieurs produits sur la permeabilite des membranes des cellules foliaires. Le paraquat, le diquat, le dinosebe et l'oxyfluorfne [2-chloro-1-(3-ethoxy-4- nitrophenoxy)-4-(trifluoromethyle) benzene] ont accru la permeabilite de la membrane des cellules foliaires, apres une exposition pendant 12 heures ou moins. Une huile‘aromatique’a provoque une augmentation importante de la permeabilite 2,5 minutes apres le traitement. l'augmentation de la liberation d'eelectrolytes a ete en relation avec la liberation d'acides amines solubles a partir de disques foliaires mais la premiere methode sest revelee plus sensible. l'augmentation de la permeabilite de la membrane cellulaire a ete aussi associee avec des symptomes de degâts, tels que l'apparition de zones necrotiques sur les feuilles. Le chlorprophame, le linuron, l'azide de sodium, le glyphosate et le 2,4-D a 10−3M, de meme que l'agent de surface X-77 a 1 % et une huile isoparaffinique, ňont pas altere la permeabilite des cellules foliaires, 12 heures apres le traitement. La lumiere sest revelee necessaire pour quele paraquat et l'oxyfluorfene alterent la permeabilite des cellules foliaires. Le paraquat et l'oxyfluorfene ont provoque un accroissement important de la permeabilite des cellules foliaires dans un mutant de soja a feuilles jaunes, par rapport aux feuilles vertes normales. Avec l'oxyftuorfene, cette difference dans la permeability a ete plus grande qu'avec le paraquat et elle a ete A associee e des symptomes necrotiques dans le mutant jaune; le paraquat ňa pas provoque de symptomes de degâts. Zusammenfassung Die WirKung von vier Herbiziden und zwei Olen auf die Permeabilitat der Btattzellmembran Fur Untersuchungen zur Wirkung verschiedener Substanzen auf die Permeabilitat von BlattZeilmembranen wurde als Hauptkriterium die Abgabe von Elektrolyten aus Blattscheiben behandelter Phaseolus vulgaris L. - Pflanzen benutzt. Paraquat, Deiquat, Dinoseb und Oxyfluoren [2-Chlor-1-(3-athoxy-4-nitro-phenoxy)-4-(trifluormethyl)benzol] erhohten nach 12-stundiger oder kurzerer Expositionsdauer die Permeabilitat der Blattzellmembran. Ein‘aromatisches’Ol bewirkte 2,5 Minuten nach der Behandlung eine verstarkte Permeabilitat. Zunahmen in der Abgabe von Elektrolyten waren auch mit einer Abgabe loslicher Aminosauren aus den Blattscheiben verbunden; die Messung der abgegebenen Elektrolyten war aber die empfindlichere Methode. Eine gesteigerte Zellmembranpermeabilitat war in allen Fallen miteiner Zunahme von Schadsymptomen, wie Blattnekrosen, verbunden. Chlorpropham, Linuron, Natriumazid, Glyphosat und 2,4-D bei 10−3 M, genauso wie X-77 (Netzmittel) bei 1% und ein nicht phytotoxisches Isoparaffinol, bewirkten 12 Stunden nach der Behandlung keine Veranderung in der Permeabilitat der Blattzellmembranen. Fur die Wirkung von Paraquat und Oxyfluoren auf die Zellpermeabilitat war Licht notwendig. Bei Verwendung einer Sojabohnenmutante mit gelben Blattern, verursachten Paraquat und Oxyfluoren eine erhohte Blattzellpermeabilitat, als es bei normal griinen Blattern der Fall war. Dieser Unterschied war mit Oxyfluoren grosser als mit Paraquat und ging bei der gelben Mutante mit starken Nekrosen einher, wogegen Paraquat keine Schadsymptome hervorrief.

Denaturation of porcine pepsin during Cheddar cheese manufacture

Abstract: Porcine pepsin was rapidly denatured in phosphate buffers, pH 6·4–6·7, in the temperature range 31–39 °C and was only slightly more stable in milk under similar conditions. However, the enzyme was considerably more stable in Cheddar cheese curd in which the extent of denaturation was very markedly influenced by the pH of the milk at setting. Under normal cheese-making conditions, porcine pepsin was about equally stable with chymosin. Two modifications of the cheesemanufacturing procedure were developed which permit the manufacture of cheese almost free of coagulant and suitable for the assessment of the contribution of starter proteinases to proteolysis during cheese ripening.

Cholestrol in muscle membranes

Abstract: The composition of skeletal muscle microsomes is reviewed. Evidence for the involvement of cholesterol in the transport of calcium by vesicles derived from the sarcoplasmic reticulum is considered. Results obtained by non aqueous extractions of skeletal muscle microsomes, and by use of the cholesterol analogue 20, 25 diazacholesterol indicate that cholesterol is not involved in calcium transport by vesicles of sarcoplasmic reticulum origin. Use of density perturbation procedures indicating that cholesterol is present in muscle membranes other than those of the sarcoplasmic reticulum involved in calcium transport is discussed. The distribution of membranal cholesterol is muscle is compared to that in other tissues.

The evolution of nonlinear standing waves in bounded media

Abstract: The evolution of small amplitude disturbances in a bounded medium, under fixed and nearly fixed end conditions, is considered. The various physical effects accounted for are amplitude dispersion, frequency dispersion and dissipation due to both radiation of energy out of the medium and rate-dependence of the medium. In a nonlinear geometrical acoustics theory the transport equations which determine the signal carried by a component wave have the form of a simple wave equation, Korteweg-de Vries equation, damped simple wave equation and Burgers' equation.

The Canadian rebellion losses bill of 1849 in British politics

Abstract: (1977). The Canadian rebellion losses bill of 1849 in British politics. The Journal of Imperial and Commonwealth History: Vol. 6, No. 1, pp. 3-22.

Factors associated with undergraduate marijuana use in Cork.

Abstract: The purpose of this study was to estimate the prevalence of cigarette, alcohol and drug use among undergraduates in University College, Cork. A precoded questionnaire was sent to systematically chosen group of students (n=458). The response rate was 97%. 23% of males and 13% of females have taken marijuana at least once. Student use of marijuana was significantly related to leisure, money available, belief in God, frequency of attendance at religious services, attitudes to marriage partner drinking and to misdemeanour considered most serious. It appears that peer group pressures as illustrated by friends' drug taking, siblings' drug taking, encouragement by friends to take drugs and faculty, had a greater influence on student marijuana use than family related factors. Current cigarette use, pattern of drinking behaviours, use of other drugs and attitudes to future marijuana use also had significant associations with marijuana-related behaviour.

Uptake patterns of soil‐applied 45Ca and 32P in some legume species as influenced by differential trifluralin placement

Abstract: Summary: The effect of localized placement of trifluralin on uptake patterns of soil-applied 45Ca in vetch (Vicia sativa L.), pea (Pisum sativum L.) and soybean (Glycine max) and 32P in vetch and pea was investigated in two soil zones in the roots and in the shoot zone before and after plant emergence. When trifluralin was in the upper root zone severe inhibition of lateral roots occurred as well as a marked decrease in uptake of 45Ca and 32P from this zone. Root growth in the lower zone was unaffected, but uptake of 45Ca and 32P was slightly reduced. Compensatory adventitious root growth as well as a marked increase in uptake of 45Ca and 32P occurred in the shoot zone. Neither root growth nor uptake of 45Ca or 32P in the upper root zone were affected by the presence of trifluralin in the lower root region. When trifluralin was placed in the shoot zone after plant emergence, adven-titious roots on the shoots were inhibited and uptake of 45Ca and 32P was reduced. Resume: Modifications des modalites d'absorption du 45Ca et du 32P appliques sur le sol dans quelques especes de legumi-neuses, sous l'influence de differents sites de placement de la trifluraline L'effet du placement localise de la trifluraline sur les modalites d'absorption du 45Ca applique sur le sol dans une culture de vesce (Vicia sativa L.) de pois (Pisum sativum L.) et de soja (Glycyne max), ainsi que du 32P sur des cultures de vesce et de pois, a eteetudie dans deux zones du sol, celles des racines et celles des jeunes pousses, avant et apres la levee de la plante. Lorsque la trifluraline a ete placee dans la zone superieure des racines, une inhibition severe des racines laterales s'est produite ainsi qu'une diminution marquee de l'absorption de 45Ca et 32P a partir de cette zone. La croissance des racines dans la zone inferieure ňa pas ete affectee mais l'absorption de 45Ca et 32P a ete legeerement reduite. Une croissance compensatrice des racines adventives ainsi qu'un accroissement marque de l'absorption de 45Ca et 32P sest manifeste dans la zone des jeunes pousses. Ni la croissance des racines ni l'absorption de 45Ca ou de 32P dans la zone superieure des racines ňont ete affectees par la presence de tri-fluraline dans la zone inferieure des racines. Lorsque la trifluraline a ete placee dans la zone des jeunes pousses, apres la levee de la plante, les adventices sur les pousses ont ete inhibees et l'absorption de 45Ca et de 32P a ete reduite. Zusammenfassung Der Einfluss von unterschiedlich lokalisiertem Trifiuralin auf die Aufnahme von bodenappliziertem 45Ca und 32P bei einigen Leguminosenarten Es wurde die Wirkung von in die Wurzel und in die Sprosszone appliziertem Trifluralin auf die Aufnahme von bodenappliziertem 45Ca bei Wicken (Vicia sativa L.), Erbsen (Pisum sativum L.) und Sojabohnen (Glycine max), sowie von 32P bei Wicken und Erbsen vor und nach dem Auflaufen der Pflanzen untersucht. Trifluralin in der oberen Wurzelzone bewirkte eine starke Hemmung der Seitenwurzeln und furte zu einer verminderten 45Ca und 32P-Aufnahme. Das Wurzelwachstum in der unteren Zone wurde nicht beeintrachtigt, die 45Ca und 32P-Aufnahme ging aber leicht zuruck. In der Sprosszone wurde eine verstarkte Adventivwurzelbildung, sowie eine deutlich erhohte 45Ca- und 32P-Aufnahme festgestellt. Bei Anwesenheit von Trifluralin in der unteren Wurzelzone wurde weder das Wurzelwachstum noch die 45Ca- oder die 32P-Aufnahme in der oberen Wurzelzone beeinflusst. Nach dem Auflaufen hemmte in die Sprosszone appliziertes Trifluralin die Ausbildung von Adventivwurzeln der Sprosseund verminderte die 45Ca-und 32P- Aufnahme.

A theoretical model of the effect of wind-gusting on rain-induced cross-polarization

Abstract: It is now generally accepted that a correlation exists between crosspolarization and mean wind speed. In a recent paper by Brussaard, an explanation was offered for preferred canting angle of raindrops based on the wind profile effect. Using this method a different effective mean canting angle may be obtained for each drop size from a knowledge of the mean wind speed and the type of terrain. However, the canting angles of all the drops are in the same quadrant. In this paper a theoretical model for wind gusting, based on detailed observations of storms, is presented. This model is used to provide an explanation for raindrop canting angle distribution other than the wind profile effect. The validity of the model was tested, firstly against the photographic measurements of Saunders and secondly predicted values of crosspolarization are compared with measurements made by Semplak.

A Spectral Mapping Theorem for Holomorphic Functions

Abstract: 1. Suppose A is a complex Banach algebra, with identity 1+0. Recall the left spectrum o-left(a) of an n-tuple aEA", defined ([2] Definition 1.1) as the set of scalar n-tuples s ~ C" for which {a j s j} generates a proper left ideal of A. The right spectrum is exactly similar, and their union a A (a) is called the joint spectrum. If a e A " is a commuting n-tuple, and if B~_A is a closed commutative subalgebra containing 1 and the aj, then the functional calculus for B operates on a: whenever g: U ~ C is holomorphic on an open set U ~ C" containing the spectrum a~(a) of a with respect to B we get ([1] Theorem 4.1) a well-defined element g (a) E B ~ A, together with natural properties of the mapping g ~ g (a) ([1] Theorems 4.2-4.6). We would like to observe here that the element g(a)EA is independent of the particular commutative subalgebra B, and subject to a "remainder theorem":

Prospects of cure in lymphocyte-predominant Hodgkin's disease.

Abstract: This report concerns a particular benign histologic variant of Hodgkin’s disease, the lymphocyte-predominant category of the Rye classification. The group of 24 cases, all involving localized disease, was first reported in 1960, and is now reappraised, incorporating subsequent data. The interpretations of the original findings are confirmed and elaborated. A characteristic feature had been the long relapse-free and symptom-free survival period, which gave a false impression of security but was followed in some instances by disseminated disease, usually after 5–15 years. The proportion of such cases is now shown to be greater, and the possible quiescent period extended. Cure was suspected in some instances, and can now be considered likely in about half of the cases. The present results include a substantial number of patients who have survived for very long periods and who must be regarded as cured, though careful confirmatory autopsies are still unavailable.

The degrees of MD and ChM in British and Irish universities, 1953-70

Abstract: Summary About 80% of MBs who proceed to MD or ChM do so within 15 years of obtaining their primary medical qualification. Using this measurement as a yardstick, an attempt is made to draw a valid reflection of the award of these postgraduate degrees in the twenty university medical schools during the period 1953-70. London produced half as many MDs and ChMs as expected, Oxbridge considerably more and Scotland about half the expected ChMs.

Variation of canting-angle distribution as a function of wind velocity

Abstract: A theoretical model for wind gusting, based on detalled observation of stroms, is presented as a basis for predicting rain-induced crosspolarisation. This model is used to provide an explanation for raindrop canting-angle distribution other than the wind-profile effect.

Distribution of the calcium-ion-transport system in subcellular fractions from rabbit brain [proceedings].

Abstract: shown that the broad-specificity peptide hydrolases of intestinal mucosa and of brain in the guinea pig are closely related (O’Cuinn et al., 1975; O’Cuinn, 1976). Previous work has indicated that the degradation of biologically active peptides takes place in the soluble fraction of brain (Benuck & Marks, 1975; Marks et al., 1973; Griffiths et al., 1975). It is not surprising therefore that the degradative enzymes for the aminoacyl amides should also be present in the cytoplasm.

Thyroid teratoma in infancy

Abstract: A case of thyroid teratoma in a neonate is described. Present at birth, it was removed surgically at 12 weeks with no evidence of recurrence three years later.