Showing papers by "Université de Montréal published in 1971"
TL;DR: The rate of liberation of free acetylcholine from the surface of prostigmin-treated cerebral cortex in the freely moving cat has been determined in states of slow wave sleep, paradoxical or activated sleep, and waking.
Abstract: The rate of liberation of free acetylcholine from the surface of prostigmin-treated cerebral cortex in the freely moving cat has been determined in states of slow wave sleep, paradoxical or activated sleep, and waking. The average rate during slow wave sleep (1.2 nanograms per minute per square centimeter of cortical surface) increased during paradoxical sleep (2.2 nanograms per minute) and during waking (2.1 nanograms per minute). The rate of acetylcholine release is thus related to the electroencephalogram pattern of desynchronized activatin of the cortex rahter than to the behavioral responsiveness of the animals.
413 citations
TL;DR: In this article, a nonparametric two-sample test for location and dispersion is proposed, where two samples, the X-sample and the Y-sample of independent observations from populations with continuous distribution functions, F(x) and G(y) respectively, are con- sidered.
Abstract: SUMMARY This paper deals with a nonparametric two-sample test for location and dispersion. It Two samples, the X-sample and the Y-sample of m and n independent observations from populations with continuous distribution functions, F(x) and G(y) respectively, are con- sidered. The problem is to test the hypothesis G(x) _ F(x) versus alternatives of the form G(x) = F(ax+b) with a * 1, or b $ 0(a > 0). The proposed T statistic is a certain function of the Wilcoxon and Ansari-Bradley statistics. The Wilcoxon statistic is well known and an important property is that the two- sided test based on this statistic is consistent for testing the hypothesis F(x) = G(x) versus alternatives of the form G(x) = F(x + b) (b * 0); see Mann & Whitney (1947) and van Dant- zig (1951). The Ansari-Bradley statistic is defined as follows: in the combined samples, the observations less than or equal to the median are replaced by their ranks in increasing order and those larger than the median are replaced by their ranks in decreasing order; the statistic is the sum of these ranks for the X-sample. The two-sided test based on this statistic is consistent for testing the hypothesis F(x) = G(x) versus alternatives of the form
281 citations
Book•
01 Jan 1971TL;DR: In this article, the effect of Steroids upon resistance and non-hormone factors upon resistance was discussed, as well as the role of nonhormonal factors in resistance.
Abstract: Reviews.- I. Introduction, Terminology and Classification, Methods.- II. History.- III. Chemistry.- IV. General Pharmacology.- V. Effect of Steroids upon Resistance.- VI. Effect of Other Hormones Upon Resistance.- VII. Effect of Nonhormonal Factors upon Resistance.- VIII. Clinical Implications.- IX. Morphology.- X. Theories.- XI. Synopsis of Pharmaco-Chemical and Pharmaco-Pharmacologic Interrelations.- Summary and Outlook.- References.
197 citations
180 citations
TL;DR: There appears to be no correlation between unit firing of neurons and the spindles recorded in the area of the motor cortex to which they project in cats immobilized with gallamine during waking, slow wave sleep and fast wave sleep, but an inverse relationship in their activity to that of VL neurons is shown.
Abstract: Neuronal discharges were recorded with extracellular microelectrodes in the ventrolateral nucleus (VL) of the thalamus in cats immobilized with gallamine. These animals had been previously implanted with a plastic cylinder under general anaesthesia a few days before chronic recording. The units recorded responded monosynaptically to brachium conjunctivum (BC) stimulation and were at times identified as true thalamo-cortical relay cells by antidromic activation from motor cortex stimulation. The responses obtained from these neurons to single shock stimuli applied to BC were examined during spontaneous episodes of waking (W), slow wave sleep (SWS) and fast wave sleep (FWS).
156 citations
TL;DR: In this article, a horizontal and vertical sampling of the atmosphere has been performed to study the form of Montreal's urban heat island, showing that the lowest layers of the urban atmosphere become progressively modified as air moves toward the centre of the city.
Abstract: Horizontal and vertical sampling of the atmosphere has provided new information on the form of Montreal's urban heat island. The horizontal pattern under clear skies with light winds shows a major heat island, with marked gradients at the periphery, and a multicellular inner core. Retarded urban cooling rates in the evening yield a maximum heat-island intensity around midnight. Combined horizontal and vertical temperature surveys show that under conditions of strong rural stability, the lowest layers of the urban atmosphere become progressively modified as air moves toward the centre of the city. The change in the form of the potential temperature profile is in good agreement with Summers' internal boundary-layer hypothesis. In Montreal differing heights of heat and SO2 emission appear to produce more than one internal layer. SO2 observations, and heat input calculations reveal two major emission sources in Montreal; one associated with an industrial complex, and the other with the downtown core.
149 citations
TL;DR: Aliphatic alcohols tested for ability to potentiate the toxicity of carbon tetrachloride in mice displayed potentiating ability and produced elevated serum enzyme activities and the most marked potentiation was produced by isopropanol.
143 citations
TL;DR: In this article, the authors describe the isolation, purification and preliminary characterization of seven new lipopolysaccharide antigens which were obtained from strains representative of each of the seven protective serotypes identified by Fisher et al.
Abstract: ONE of the most serious opportunistic bacterial pathogens is Pseudomonas aeruginosa1 and the inability of the common antimicrobial agents to combat such infections suggested the investigation of specific immunological prophylactic and therapeutic approaches. Therefore Fisher et al. began to develop a new serotype schema as a prerequisite for an immunizing preparation which would protect humans against the most prevalent strains of Pseudomonas. This communication describes the isolation, purification and preliminary characterization of seven new lipopolysaccharide antigens which were obtained from strains representative of each of the seven protective serotypes identified by Fisher et al.2.
102 citations
TL;DR: The aim is to find a schedule that minimizes the elapsed time to complete all jobs and presents solution algorithms for this problem when job splitting is permitted and whenJob splitting is not permitted.
Abstract: We consider the scheduling of n tasks on a single resource. Each task becomes available for processing at time a i , must be completed by time b i , and requires d i time units for processing. The aim is to find a schedule that minimizes the elapsed time to complete all jobs. We present solution algorithms for this problem when job splitting is permitted and when job splitting is not permitted. Then we consider several scheduling situations which arise in practice where these models may apply.
92 citations
TL;DR: In this article, the vacuum ultraviolet spectra from 2000 to 1200A of methanol, ethanol, n-propanol, iso-Propanol and some of their fluorinated derivatives were measured in the gas phase.
83 citations
TL;DR: In this article, the electronic transport properties of slightly reduced pure strontium titanate have been studied at low temperatures between 2 and 300 K and the authors concluded that an explanation of these in terms of a model of impurity-band conduction is appropriate.
Abstract: The electronic transport properties of slightly reduced pure strontium titanate have been studied at low temperatures between 2 and 300 \ifmmode^\circ\else\textdegree\fi{}K. The temperature dependence of resistivity, Hall coefficient, and Hall mobility showed different features from previous results for doped and reduced crystals with higher carrier concentrations. Specifically, the mobility at liquid-helium temperatures is small (5-700 ${\mathrm{cm}}^{2}$/V sec) and increases with carrier concentration. Optical-absorption measurements showed the existence of several compensating acceptor levels and that the dominant mechanism of electron scattering was by longitudinal optical phonons at room temperature. Further, the data show that a specialized form of ionized-impurity scattering may play a role at low temperatures. A discussion of our experimental results is presented and it is concluded that an explanation of these in terms of a model of impurity-band conduction is appropriate.
TL;DR: In this article, the first singlet-singlet transition of highly branched paraffins leads to an excited state with considerable Rydberg character, and the importance of outer atomic orbitals is stressed.
Abstract: CNDO, INDO and RCNDO (CNDO including higher (Rydberg) atomic orbitals in the basis) calculations completed by first order configuration interaction were performed on straight chain and branched chain paraffins. The results interpret reasonably the main characteristics of the observed electronic spectra. The importance of outer atomic orbitals is stressed and it is found that the first singlet-singlet transition of highly branched paraffins leads to an excited state with considerable Rydberg character.
TL;DR: It can be concluded therefore that microsomal enzyme-induction accounts for the remarkable resistance-increasing effect of this steroid against many toxicants.
TL;DR: The XLAN as discussed by the authors is one of the principal hemicelluloses which may constitute up to 35% of the dry weight of hardwoods1 and is composed of a backbone of β-(1→4′)-linked anhydro-D-xylose units with occasionally attached L-arabinose and 4-O-methyl-glucuronopyranosyl side groups.
Abstract: XYLAN is one of the principal hemicelluloses which may constitute up to 35% of the dry weight of hardwoods1. It is composed of a backbone of β-(1→4′)-linked anhydro-D-xylose units with occasionally attached L-arabinose and 4-O-methyl-glucuronopyranosyl side groups.
TL;DR: It is suggested that neuronal depolarization and possibly glial cells may play a role in the generation of the DC shifts of the ACh paroxysm as shown for direct cortical responses and evoked potentials by Castellucci and Goldring (1970).
TL;DR: The authors report their experience over a 14 month period in the treatment of 20 parkinsonian patients with the combination of levodopa and an inhibitor of peripheral dopa decarboxylase, Ro 4‐4602, which appears to offer distinct advantages.
Abstract: The authors report their experience over a 14 month period in the treatment of 20 parkinsonian patients with the combination of levodopa and an inhibitor of peripheral dopa decarboxylase, Ro 4‐4602. The results obtained are comparable to those previously reported from the same center with levodopa alone and, in fact, appear to offer distinct advantages. The average daily dose of levodopa required for satisfactory results (after 3 months of treatment) was reduced from 4.S Gm. of levodopa alone to SOD mg. on the combination. The maximum daily dose of Ro 4‐4602 recommended to obtain this effect is 200 mg.
TL;DR: In this paper, a lava series from the 1959 Kilauea Iki eruption of Hawaii has a compositional range of 7.0 to 19.0% MgO which has already been shown to be due to olivine fractionation only.
TL;DR: It is demonstrated that ethanol depletes endogenous 5-HT from its storage site by indicating an inhibitory effect upon the turnover rate of brain 5- HT.
TL;DR: It is suggested that the better performance of A. pisum on diets containing 35% sucrose was caused by some contaminant present in sucrose and essential for aphid growth and reproduction, which was provided in near optimum amounts only when the sucrose concentration was at 35%, and was not necessarily a result of high concentration of sucrose itself.
Abstract: Sucrose at a concentration of 10% and above in a chemical diet was phagostimulatory to 1st-stage nymphs of the pea aphid, Acyrthosiphon pisum (Harris) (Homoptera: Aphididae). The total amount of sucrose ingested during the 1st 24 hours (hr) increased with the rise from 5 to 50% sucrose concentration in the diet, but diet uptake in microliters per aphid was highest when sucrose concentration was 10–25%. Nymphs gained more weight during the 1st 24 hr on diets containing 20–25% sucrose than on those containing lower or higher concentrations of sucrose. Similar results on weight gains were observed after 48 hr, but after 72 hr, the highest weight gain was observed on diets containing 35% sucrose. Aphids on 0–30% sucrose diets did not become adults whereas those on 35% sucrose diets were reared continuously for several generations.
Generally similar results were obtained when 1st-stage nymphs were fed on a 30% sucrose diet for 20 hr prior to their transfer to diets containing different concentrations of sucrose, with the main difference that such nymphs ingested relatively larger amounts of the sucrosefree diet. However, after 24 hr of feeding, aphids lost weight on the 0 and 5% sucrose diets, suggesting that at least 10% sucrose was necessary for normal absorption. Aphids reproduced mainly on the 10, 15, and 35% sucrose diets, and the highest number of progeny was produced on the latter diet, where aphids were reared for several generations. It is suggested that the better performance of A. pisum on diets containing 35% sucrose was caused by some contaminant (possibly a heavy metal) present in sucrose and essential for aphid growth and reproduction, which was provided in near optimum amounts only when the sucrose concentration was at 35%, and was not necessarily a result of high concentration of sucrose itself.
TL;DR: A new algorithm is described for this hyperbolic programming problem which produces an optimal solution by scanning just once the set of fractions to be analysed, and a “branch and bound” type algorithm for this problem is described.
Abstract: In the first part of this paper we study the unconstrained {0, 1} hyperbolic programming problem treated in [1]. We describe a new algorithm for this problem which produces an optimal solution by scanning just once the set of fractions to be analysed. This algorithm shows better computing performance than the one described in [1].
In the second part we study the {0, 1} hyperbolic programming problem with constraints given by inequalities on nondeereasing pseudo-boolean functions. We describe a “branch and bound” type algorithm for this problem.
TL;DR: The membrane structure was found to be trilamella: a middle layer about 200 A thick, which originally was the vitelline membrane, and about 175 A thick peripheral layers organized by the “crystalline material” from the cortical granules.
TL;DR: It seems likely that the preexisting glycogen foci in either the cytoplasm or the nucleus may serve as active synthetic sites of glycogen in the hepatoma cells.
TL;DR: Pretreatment with spironolactone or oxandrolone, followed by concomitant administration of these steroids and digitoxin or indomethacin maintains the animals in excellent condition throughout the period of spironoliactone-pretreated administration (in the present experiment, 2 mo).
TL;DR: In the Grand Canyon of the Rio Grande de Santiago of the Mexican Cordilleran Volcanic Province as discussed by the authors, a number of oriented cores of 2.5 cm diameter have been drilled from seven bodies comprising part of a sequence of ignimbrite sheets interdigitated with basalts and basaltic andesites.
Abstract: Seventy-two oriented cores of 2.5 cm diameter have been drilled from seven bodies comprising part of a sequence of ignimbrite sheets interdigitated with basalts and basaltic andesites, in the Grand Canyon of the Rio Grande de Santiago of the Mexican Cordilleran Volcanic Province. Field observations and whole-rock analyses reveal two groups: an olivine basalt-high alumina basalt-basaltic andesite series, and a sequence of rhyolitic ignimbrite sheets, with some rhyolitic and obsidian lava flows. Crystal separation, partial melting of oceanic tholeiite, and simple mixing of basalt and oceanic sediments or granodiorite cannot acceptably explain the observed fractionation trends. The favored origin is a partial melting of a second or third stage product, such as a basalt or amphibolite enriched in K, Rb, Th, and Pb, relative to oceanic tholeiite. The observed fractionation trends are parallel to those of the andesite-dacites of the Mexico City region, but the Rio Grande de Santiago rocks have a systematically higher K 2 O/SiO 2 ratio, which can be explained by a greater magma generation depth. The paleomagnetic polarity sequence with decreasing age is R,R,N,R,R,N,N, providing easily measurable markers of high potential stratigraphic value. The mean virtual geomagnetic pole is not significantly different from the present spin axis. The potassium-argon analyses show that the sampled section contains two distinct volcanic episodes, from approximately t = 4.6 to 5.5. m.y. and from approximately t = 8.7 to 9.5 m.y. The polarities recorded by the youngest volcanic cycle are consistent with the predicted polarity time scale of Heirtzler and others (1968), while the older cycle polarities can be explained by minor modification of the predicted polarity scale, to include a short period of reversed polarity between 9.0 and 9.5 m.y., within the normal polarity anomaly 5 (t = 8.79 to 9.94 m.y.) of the time scale.
TL;DR: It is hypothesized that early appearing substances previously described as bilirubin may be metabolites of ANIT capable of undergoing diazotization under certain conditions.
TL;DR: The data suggest that steroids may decrease the concentration of a toxic polycyclic hydrocarbon in target cells by stimulating the metabolism of DMBA and/or its metabolites.
TL;DR: The results of the rearing tests indicated that a high concentration of sucrose, an alkaline p H of the diet, and the inclusion of trace amounts of the metals, Cu, Fe, Mn, and Zn, in sequestrene forms, were all necessary for an improved performance of the pea aphid on chemically defined diets.
Abstract: Acyrthosiphon pisum (Harris) was reared for more than 7 successive generations on a chemically defined diet that combined features of the diets described by Auclair in 1965 for the pea aphid and by Dadd and Mittler in 1966 for the green peach aphid, Myzus persicae (Sulzer). The results of the rearing tests indicated that a high concentration of sucrose, an alkaline p H of the diet, and the inclusion of trace amounts of the metals, Cu, Fe, Mn, and Zn, in sequestrene forms, were all necessary for an improved performance of the pea aphid on chemically defined diets.