Showing papers by "University of Manitoba published in 1974"
TL;DR: In this article, the multiplet splittings of core $p$-vacancy levels have been observed in various transition-metal complexes and in some rare-earth as well as actinide complexes.
Abstract: The multiplet splittings of core $p$-vacancy levels have recently been observed in various transition-metal complexes and in some rare-earth as well as actinide complexes. This paper presents the calculation of the multiplet structure of core $p$-vacancy levels in the Hartree-Fock free-ion approximation. The spin-orbit and crystal-field effects have been included. The cases studied are ${\mathrm{Mn}}^{2+}$ in Mn${\mathrm{F}}_{2}$ and the free ion ${\mathrm{Fe}}^{3+}$. For $3p$ vacancies these effects appear to be unimportant from the point of view of photoelectron spectroscopy owing to the limited resolution of the technique. For $2p$ vacancies the spin-orbit interaction is comparable to the electrostatic interaction between the electrons and both the interactions must be considered simultaneously. The conclusion is that the x-ray photoelectron spectra of inner-core electrons are more suitable for chemical analysis than those of outer electrons which, in addition, contain large correlation and many-body effects.
557 citations
TL;DR: The effect of pH on the K(m) values for ammonia was studied in its oxidation by Nitrosomonas cells and cell-free extracts, suggesting (NH(3)) rather than ( NH(4) (+)) as the actual substrate for oxidation.
Abstract: The effect of pH on the Km values for ammonia was studied in its oxidation by Nitrosomonas cells and cell-free extracts The Km values decreased markedly with increasing pH, suggesting (NH3) rather than (NH4+) as the actual substrate for oxidation
427 citations
TL;DR: A spectral analysis of the trajectories of 7 body markers in the saggital plane, and of the knee angle as determined by 4 of these markers, indicates that, for the marker trajectories, 99·7 per cent of the signal power lies below the 8th harmonic.
412 citations
TL;DR: With stimulation, the pH, ionic strength and the concentrations of protein, sodium, calcium, chloride and bicarbonate increased in proportion to flow rate, the potassium concentration remained almost constant whilst the magnesium and phosphate concentrations decreased, the former being independent of stimulated flow rate but the latter being inversely related to flow rates.
293 citations
TL;DR: In this paper, a shortened radioimmunoassay for serum aldosterone has been made possible by the development of a highly specific antiserum for the 3-oxime derivative.
Abstract: A shortened, simplified radioimmunoassay for serum aldosterone has been made possible by the development of a highly specific antiserum for aldosterone. This high specificity is largely due to the careful purification of the aldosterone-3-oxime derivative. Using 50% displacement of 1,2-3H-aldosterone as a measure, no other steroid cross-reacts to a degree greater than 0.015% (18-OH-DOC) and most cross-react less than 0.00003%. Recovery, accuracy and sensitivity are quite satisfactory using only serum extraction with methylene chloride and no further separation. The normal range found is comparable with others reported (3–35 ng/100 ml) although women are shown to have more variable levels than men.
204 citations
TL;DR: In this article, a radiotracer method was used to measure rates of oxidation of methane to cell material, extracellular products, and carbon dioxide in two lakes and indicates that methane oxidation occurred in a narrow band where methane and oxygen occurred together in the water column.
Abstract: A radiotracer method which measures rates of oxidation of methane to cell material, extracellular products, and carbon dioxide has been applied to two lakes and indicates that methane oxidation occurred in a narrow band where methane and oxygen occurred together in the water column. Oxidation rates of 1.0 µM hr−1 were recorded in a eutrophic lake; rates in a meromictic lake reached 0.15 µM hr−1. Usually a third of the carbon from oxidized methane was found in cell material and extracellular products and the rest was converted to carbon dioxide. This ratio was observed to change at very low oxygen concentrations.
197 citations
TL;DR: The significance of skull fractures in children and the significance of cephalhematoma in newborns, Radiology 101: 151, 1971, is illustrated.
181 citations
TL;DR: Maternal and fetal cardiovascular and acid-base changes during general anesthesia with halothane and isoflurane in 16 near-term pregnant ewes with chronically implanted intravascular catheters and uterine-artery flow probes found that uterine blood flow decreased and the fetuses became hypoxic and acidotic.
Abstract: To determine the nature and extent of fetal metabolic changes during administration of inhalation anesthesia to the mother, the authors studied maternal and fetal cardiovascular and acid-base changes during general anesthesia with halothane and isoflurane in 16 near-term pregnant ewes with chronical
127 citations
TL;DR: The main conclusion from the study is that the use of prophylactic antibiotics in third molar surgery is unnecessary unless specific systemic factors are present.
112 citations
TL;DR: Cis-Jasmone (I), a constituent of the Jasminum genus, and dihydrojasmone(II), which is present in bergamot oil, are important perfume ingredients as discussed by the authors.
100 citations
TL;DR: In this article, four investigations of the affect-pupil size relationship are reported as attempts to test Hess's (1965) attraction-dilation and aversion-constriction hypotheses.
Abstract: Four investigations of the affect-pupil size relationship are reported here as attempts to test Hess’s (1965) attraction-dilation and aversion-constriction hypotheses. In the first 2 studies, no evidence was found for a relationship between pupil size and frequency of exposure to a stimulus as defined by Zajonc (1968). However, it was observed that the stronger a stimulus was rated in terms of affect (like-dislike), whether positive or negative, the larger the pupil size. Pupil size at the neutral point was not smallest, as expected, but was elevated, relative to the points adjacent to it. Two additional studies, using a pseudo task which induced feelings of success or failure, confirmed the previous findings. A positive relationship was found between pupil size and affect intensity, and again, elevated pupil size at the neutral points. There was no evidence of constriction to any stimulus, positive or negative, in any of the 4 studies. It was concluded that pupil size is linearly related to the intensity continuum of affect and curvilinearly related to its valence (positive-negative) continuum.
TL;DR: The secretory pattern of luteinizing hormone (LH) and testosterone (T) and the temporal relationship between the two were studied in 4 mature rams and in January for the 2 Finnish Landrace rams differed considerably from that in August.
Abstract: The secretory pattern of luteinizing hormone (LH) and testosterone (T) and the temporal relationship between the two were studied in 4 mature rams (2–3 yr of age). Blood was obtained from the jugular by venipuncture at 20-min intervals for a 24 hr period from each of 2 crossbred rams in May and 2 Finnish Landrace rams in August and January. Serum levels of LH and T were determined in duplicate by RIA. LH estimations have been expressed in terms of ng NIH-LH-S14/ml. Rams sampled in May and August exhibited similar LH and T secretory patterns. Baseline levels of LH fluctuated from 0.20–0.94 ng/ml. During the 24-hr period each ram exhibited from 3–5 LH peaks averaging 9.59 ± 1.50 ng/ml and occurring at intervals of 6.9 ± 0.6 hr. Within 1 hr following each LH peak the blood T level consistently increased from baseline values of 0.30–1.53 ng/ml to peak values averaging 9.02 ± 1.53 ng/ml. The secretory pattern in January for the 2 Finnish Landrace rams differed considerably from that in August. For each ram 7 L...
TL;DR: In this paper, a simple frequency-domain method for measurement of the dielectric properties of materials is described, and theoretical analysis of the frequency dependence of the reflection coefficient of a shunt lumped capacitor located at the end of a transmission line and filled with a very small amount of the Dielectric (typically a few microliters) is given.
Abstract: A simple frequency-domain method for measurement of the dielectric properties of materials is described. Theoretical analysis of the frequency dependence of the reflection coefficient of a shunt lumped capacitor located at the end of a transmission line and filled with a very small amount of the dielectric (typically a few microliters) is given. Analysis and calculations of the overall uncertainty in permittivity measurements, as well as experimental results for some normal alcohols, are presented and limitation of the method discussed.
TL;DR: This study has used the same assay with minor modifications to identify and measure plasma placental lactogen concentrations in sheep during pregnancy and has compared the secretory pattern of this new hormone with plasma concentrations of progesterone and pituitary prolactin.
Abstract: HUMAN and monkey placental lactogens (PL) have been isolated and characterised biologically and chemically1–3 and reports have appeared identifying a placental lactogen in rats4–6, mice7 and goats8. More recently rat serum PL concentrations have been determined quantitatively with a radioreceptor assay9. In the present study we have used the same assay with minor modifications to identify and measure plasma placental lactogen concentrations in sheep during pregnancy and have compared the secretory pattern of this new hormone with plasma concentrations of progesterone and pituitary prolactin.
TL;DR: Allergic and respiratory investigations were performed in 17 subjects with respiratory symptoms and occupational exposure to grain dust, finding a good correlation between the hypersensitivity reactions on skin testing and on bronchial provocation.
Abstract: Allergic and respiratory investigations were performed in 17 subjects with respiratory symptoms and occupational exposure to grain dust. Common symptoms included chronic cough and sputum production, grain fever, wheezing and dyspnea on exposure to grain dust. Results of pulmonary function tests demonstrated a pattern of obstructive airway disease. Immediate hypersensitivity to grain dust was common. Both immediate and late reactions were observed on inhalation challenge studies. There was a good correlation between the hypersensitivity reactions on skin testing and on bronchial provocation. Inhalation of crude grain dust extract may produce systemic symptoms of malaise, myalgia, headache, and leukocytosis even in normal subjects. There was no evidence of precipitin-mediated hypersensitivity.
TL;DR: This article examined the relationship between locus of control and two academic related variables: study habits and attitudes, and college academic performance, and found that study habits were correlated with academic performance.
Abstract: This research examined the relationship between locus of control and two academic-related variables: study habits and attitudes, and college academic performance. Subjects were administered (a) the...
TL;DR: By karyotype analysis of a series of colonies arising from a specimen of amniotic fluid, the interpretation of chromosomal mosaicism, when present, should be rendered less ambiguous.
Abstract: Extract: The occurrence of chromosomal mosaicism in 48 amniotic fluid cell cultures was studied. Chromosome preparations were made by in situ processing and the karyotype was established from the analysis of a series of discrete colonies, thereby reflecting more closely the chromosomal status of the original fluid sample. In 50% of cultures there were one or more colonies in which the chromosomes were entirely tetraploid, the frequency ranging from 2% to 14%. No chromosomally abnormal infants were born in these cases and tetraploidy should not be considered a reason for termination of pregnancy. Four amniotic fluid samples showed one, and in one instance two, chromosomally abnormal colonies in cultures with otherwise normal chromosomes. Three of these involved trisomy (47,XY, +C; 47,XX, +C; 47,XY, +2) and two involved translocation (46,XY,t(Bq + ;Cq-); 46,XX,t(2p-;Eq+)). In no instance did the minor aberrant cell type observed in the amniotic fluid appear in the neonate. The frequency with which chromosomally aberrant cell types appear in normal amniotic fluid cell cultures makes prenatal diagnosis of a true mosaic extremely hazardous. Speculation: Cultured amniotic fluid cells proliferate as discrete colonies from which chromosome preparations can be obtained using in situ processing. By karyotype analysis of a series of colonies arising from a specimen of amniotic fluid, the interpretation of chromosomal mosaicism, when present, should be rendered less ambiguous.
TL;DR: In this paper, the energy dependence of the real central potential (as indicated by the volume integral per nucleon and by the strength parameter) can be represented by a linear relation if a limited energy range is chosen.
Abstract: Measurements have been made of the differential cross sections for $p+^{208}\mathrm{Pb}$ elastic scattering at mean proton energies of 21.0, 24.1, 26.3, 30.5, 35.0, 45.0, and 47.3 MeV. Measurements have also been made of the differential cross sections and polarizations at 185 MeV. These data together with the data in the energy range 15-1000 MeV available in the literature have been analyzed in terms of a standard 11-parameter optical model. Relativistic corrections to the optical-model analysis were introduced. The energy dependence of the real central potential (as indicated by the volume integral per nucleon and by the strength parameter) can be represented by a linear relation if a limited energy range is chosen. This linear energy relation cannot be extrapolated to higher energies since it makes the real central potential repulsive at too low an energy as indicated by the results of optical-model analyses of proton scattering data above 200 MeV. A logarithmic energy dependence gives a reasonable presentation of the volume integral per nucleon of the real central potential for energies up to 1 GeV.NUCLEAR SCATTERING $^{208}\mathrm{Pb}(p,p)$, $T=21.0, 24.1, 26.3, 30.5, 35.0, 45.0, \mathrm{and} 47.3$ MeV, measured $\ensuremath{\sigma}(\ensuremath{\theta})$, $\ensuremath{\theta}=15\ensuremath{-}167.5\ifmmode^\circ\else\textdegree\fi{}$; $T=185$ MeV measured $\ensuremath{\sigma}(\ensuremath{\theta})$, $P(\ensuremath{\theta})$, $\ensuremath{\theta}=4\ensuremath{-}38\ifmmode^\circ\else\textdegree\fi{}$; optical-model analysis, previous data $\ensuremath{\sigma}(\ensuremath{\theta})$, $P(\ensuremath{\theta})$, ${\ensuremath{\sigma}}^{R}$ included.
TL;DR: It is shown that an important cause of the decrease in the functional refractory period that occurs when heart rate is increased is the change in the conduction time of the regular beats.
Abstract: The functional refractory period of atrioventricular (AV) transmission has been accepted as a measure of AV nodal refractoriness and has been assumed to be determined solely by conduction of interpolated extrasystoles through the AV node when it is partially refractory. In the present study, we found an important effect of the conduction time of the regular beats by measuring AV nodal conduction times of atrial extrasystoles from the His bundle of isolated, blood-perfused dog hearts. We separated three independent components that determine AV nodal conductivity: (1) a "basal conduction time" measured with a "postmature" extrasystole at low heart rates (<120 /min), (2) a rate-dependent increment in conduction time (previously called "fatigue") that affects both normal and premature cycles equally and (3) an exponential change in conduction time that depends entirely on the immediately preceding interval and, therefore, is not further affected by heart rate. The functional refractory period is one point defining this continuous exponential function. We showed that an important cause of the decrease in the functional refractory period that occurs when heart rate is increased is the change in the conduction time of the regular beats.
TL;DR: Serum concentrations of LH, FSH, testosterone and estradiol were measured in 6 subjects with the complete form of testicular feminization who ranged in age from 0.5–21.0 yr, and postcastration studies showed no gonadotropin suppression by dihydrotestosterone propionate, but significant suppression by testosterone Propionate.
Abstract: Serum concentrations of LH, FSH, testosterone and estradiol were measured in 6 subjects with the complete form of testicular feminization who ranged in age from 0.5–21.0 yr. The 3 postpubertal subjects showed LH levels elevated above the age-matched eugonadal male range, while serum FSH, testosterone and estradiol levels were within normal male limits. The 3 prepubertal subjects showed normal or only slightly elevated LH and FSH concentrations. Serial LH, FSH and testosterone determinations over 1 month in the 21-yr-old subject showed no cyclic variation. Stilbestrol, but not fluoxymesterone, suppressed gonadotropinand testosterone levels in this subject. In 4 subjects, including the 0.5 yr old, castration resulted in a marked increment in FSH levels and a further rise in LH levels. Postcastration studies showed no gonadotropin suppression by dihydrotestosterone propionate, but significant suppression by testosterone propionate; similar effects were seen in 4 young adult castrate “controls”. Gona...
28 Nov 1974
TL;DR: In this paper, necessary and sufficient conditions are given for the existence of edge labels from an Abelian group such that the sum of the labels incident to each vertex is r(v).
TL;DR: Strong evidence that ribonucleotide reductase is one of the lethal sites of action for these two antitumour agents is found, consistent with the view that mammalian cell variants can arise from structural gene mutations.
TL;DR: Microiontophoretic applications of adenosine 3',5'-monophosphate (cyclic AMP) to spontaneously active, electrophysiologically identified Purkinje cells of the rat cerebellum failed to mimic the strong depressant action of norepinephrine on the same cells.
Abstract: Microiontophoretic applications of adenosine 3',5'-monophosphate (cyclic AMP) to spontaneously active, electrophysiologically identified Purkinje cells of the rat cerebellum failed to mimic the strong depressant action of norepinephrine on the same cells. These findings, in combination with a reevaluation of other studies, cast doubt on the hypothesis that cyclic AMP mediates the depressant actions of norepinephrine in the cerebellum.
TL;DR: In this paper, a theoretical model based on the filamentary double injection in solids is presented, and expressions for the intensity of electroluminescence in molecular crystals as a function of applied electric field, current density, and temperature are derived.
Abstract: A theoretical model based on the filamentary double injection in solids is presented, and expressions for the intensity of electroluminescence in molecular crystals as a function of applied electric field, current density, and temperature are derived. The computed results are in good agreement with presently available experimental results for undoped and doped anthracene crystals.
TL;DR: Data indicate that calcium ions are essential for, and perhaps mediate the inhibitory effects of biogenic amines on cortical neurones, and the lack of specificity in the CNS of many aminergic antagonists is due, in part, to interactions of the drugs with common mechanisms regulating neuronal excitability, which involve calcium.