Showing papers by "University of Ottawa published in 1979"

The posterior lateral line lobe of certain gymnotoid fish: Quantitative light microscopy

Abstract: The posterior lateral line lobe of the wave species of gymnotoid fish was investigated with the Golgi technique. The posterior lobe has a laminar structure and contains II cell types differentially distributed in the various laminae (fig. 13). The major laminae, from ventral to dorsal are the deep fiber layer, containing multipolar neurons; the deep neuropil layer, containing ovoid neurons and a sub-lamina of spherical cells; the granule cell lamina, containing two types of granule cell; the plexiform laminae; the polymorphic cell lamina, containing basilar pyramids, non-basilar pyramids, giant fusiform cells, and polymorphic cells; the stratum fibrosum; the molecular lamina, containing neurons of the ventral molecule layer and stellate cells. The spherical cells are regularly distributed in their sub-lamina and appear to receive one type of primary afferent input. Another type of primary afferent input ends in the deep neuropil and granule layers, in proximity to the basilar dendrites of the granule cells and of the basilar pyramids. The basilar pyramidal cell spatially alternates with the non-basilar pyramidal cell, so that the basilar dendritic trees of nearest-neighbour basilar pyramids show almost no overlap. Descending input to the posterior lobe ends in the molecular layer, in proximity to apical dendrites of both pyramidal cells, giant fusiform cells, polymorphic cells, and one type of granule cell. There are three afferent fiber systems in the molecular layer, one running transversely, one longitudinally, and one vertically. Local circuitry in the posterior lobe is precisely organized and involves projections of granule cells onto overlying pyramidal cells. The polymorphic cell may also be involved in the intrinsic circuits of the posterior lobe.

Localized primary tumors of the pleura: an analysis of 40 cases.

Abstract: A study of 40 localized primary tumors of the pleura in the files of the Canadian Tumour Reference Centre revealed a considerable diversity in their histologic structure. Collagenized, hemangiopericytoma-like and cellular areas were the main forms of growth pattern, with half of the tumors showing a mixture of two or more of these elements. Inclusions of non-neoplastic bronchiolealveolar epithelium were frequently seen in areas of tumor adjacent to lung substance but in only one tumor was there a neoplastic component of epithelial form. Eight tumors (20%) showed evidence of malignant behavior. All of these were large and cellular at the time of initial surgery and four had mitotic counts of 10 or more/10 H.P.F. in areas. The evidence suggests that the great majority of localized pleural tumors arise from submesothelial mesenchymal elements and it is believed that the term mesothelioma should not be used in reference to these growths.

Sequencing with Series-Parallel Precedence Constraints

Abstract: One of the most important ideas in the theory of sequencing and scheduling is the method of adjacent pairwise job interchange. This method compares the costs of two sequences which differ only by interchanging a pair of adjacent jobs. In 1956, W. E. Smith defined a class of problems for which a total preference ordering of the jobs exists with the property that in any sequence, whenever two adjacent jobs are not in preference order, they may be interchanged with no resultant cost increase. In such a case the unconstrained sequencing problem is easily solved by sequencing the jobs in preference order. In this paper, a natural subclass of these problems is considered for which such a total preference ordering exists for all subsequences of jobs. The main result is an efficient general algorithm for these sequencing problems with series-parallel precedence constraints. These problems include the least cost fault detection problem, the one-machine total weighted completion time problem, the two-machine maximum completion time flow-shop problem and the maximum cumulative cost problem.

Concepts for advanced simulation methodologies

Abstract: Conventional simulation techniques have three short comings when applied to large-scale modelling : They provide an inadequate man-machine interface, they provide a poor conceptual framework, and they lack needed tools for managing data and model. These shortcomings may be ameliorated by developing new simulation languages that differentiate the function aZ elements of simulation programs and by recognizing the goals of these functional elements. This paper provides concepts for the design and implementation of such advanced simulation methodologies.

The treatment of narcolepsy-cataplexy with nocturnal gamma-hydroxybutyrate.

Abstract: Sixteen patients with narcolepsy and cataplexy were treated with gamma-hydroxybutyrate (GHB) given at night and tailored to achieve as continuous a night's sleep as possible The dosage usually consisted of 15-225 gm orally at bedtime and then one or two further 10-15 gm doses with awakenings during the night, and totaled about 50 mg/kg Apart from one patient who took only the bedtime dose, the subjective quality of night sleep improved in all patients and the number of irresistible daytime attacks of sleep and cataplexy substantially diminished Some residual daytime drowsiness remained and this usually responded well to low doses of methylphenidate Improvement has been maintained for up to 20 months without the development of tolerance Two patients experienced adverse side effects necessitating withdrawal of GHB treatment, but no serious toxic effects have occurred

Zooplankton grazing and phytoplankton species richness: Field tests of the predation hypothesis1

Abstract: The hypothesis that herbivory plays a major role in the maintenance of high algal diversity was tested over a e-year period in polyethylene enclosures at Heney Lake, Quebec. Reduction of grazing pressure resulted in a significant decrease in the number of inedible species, whereas the diversity of edible algae remained unaffected. Lowering the herbivore levels may cause an intensification of exploitative competition among phytoplankton, which favors edible species and a few inedible algae like Synedra at the expense of many inedible species that are eliminated.

Lower Class Women in the Roman Economy

Abstract: The subject of this paper is the female of the species opifiaes and tabemarii, "craftsmen and shopkeepers and all that scum of the cities," as Cicero once indiscreetly called them. We need not beli...

Quadrupole moment of the deuteron from a precise calculation of the electric field gradient in D 2

Abstract: The electric field gradient along the molecular axis at the nucleus in ${\mathrm{D}}_{2}$ has been calculated at $R=1.4$ a.u. by means of the Ko\l{}os-Wolniewicz 54-term Born-Oppenheimer wave function. The result is a confirmation of the Reid-Vaida value. A nonadiabatic calculation using a 540-term wave function (explicitly containing the vibronic component) also confirms the earlier value of the electric field gradient and necessarily, therefore, the predicted quadrupole moment of the deuteron (i.e., $Q=0.2860\ifmmode\pm\else\textpm\fi{}0.0015$ ${\mathrm{fm}}^{2}$).

Cytogenetic findings in Roberts‐SC phocomelia syndrome(s)

Abstract: Roberts syndrome and SC phocomelia syndrome are an autosomal recessive condition of prenatal and postnatal growth retardation, symmetrical limb reduction, and craniofacial abnormalities. A distinction has been made between the two syndromes on the basis of relative severity of these manifestations. Where chromosome studies have been carried out, most have been reported as normal. However, there have been two reports of consistent centromere abnormalities; one in a patient with SC phocomelia (pseudothalidomide syndrome), the other in a patient with Roberts syndrome. Four patients with similar phenotypic manifestations have recently been shown in our laboratory to have the same centromere puffing and splitting. These four patients had other clinical manifestations in common, including bilateral corneal opacities, microcephaly, absence of radii, limited extension at knees and elbows, apparent enlargement of the phallus, and survival beyond the neonatal period.

Intensive second language study in a bicultural milieu: an investigation of attitudes, motivation and language proficiency1

Abstract: The purpose of this investigation was to investigate the relation of a series of attitudinal/motivational variables to achievement in French of samples of Canadian and American adult students in an intensive French language program, and to assess the effects of the program on attitudes, motivation, and French proficiency. The results demonstrated an association between an attitudinal/motivational factor, referred to as an integrative motive, and French oral proficiency and reported satisfaction with the program for the sample of 89 Canadian students, but not for the 65 Americans, even though an integrative motive factor was obtained with both samples. Furthermore, both samples evidenced decreases in anxiety and attitudes toward bilingualism, and increases in French proficiency as a result of the program, while the American sample also demonstrated a decreased appreciation of the French Canadian community, and an increased desire to learn French. The results were interpreted as reflecting the role played by attitudes in the language learning situation, but attention was directed toward the significant influence the sociocultural background of the student can have on the nature of this role.

Towards a theory of language learning ability

Abstract: In this paper, the problem of foreign or second language learning ability in adults is examined with special attention to the “critical period” hypothesis. Although data from several studies are reviewed, discussion centers around the appropriateness of traditional research methodology in the area. The author begins with a summary of the four most frequently discussed positions on foreign or second language aptitude as they appear in the literature. He then turns to methodological issues where he argues for a shift in orientation from macrocorrelational studies to more carefully controlled micro research which embodies the developmental null hypothesis. In the third portion of the paper, he discusses three studies he has conducted on second language learning ability in adults. The author concludes by enumerating the issues he views most important for future research. He reaffirms his claim that the optimal way to study the nature of language learning ability is to focus narrowly upon specific problems in idealized contexts where extralinguistic variables are reduced to a minimum in tightly controlled designs.

Predicting Academic Achievement from Classroom Behavior

Abstract: This review focuses on a set of studies in which data are presented on the classroom behavior-academic achievement relation. Three criteria were used in selecting studies for review: (a) the study employed observational measures of classroom behavior; (b) direct links were established between behavioral measures and some index of academic achievement; and (c) the pupil was employed as the unit of analysis. Following a summary of statistically significant behavior-achievement relations, an assessment of the research is presented in terms of concepts from the testing model. Thus, questions are raised regarding the reliability of the behavioral categories, their validity, and the nature of the relation that exists between behaviors and achievement. The review concludes with a summary of recommendations for future research on the issue.

Membrane‐bound phospholipid desaturases

Abstract: This review covers studies on membrane-bound phospholipid desaturases in yeast and rat liver carried out in this laboratory In yeast the desaturase system was shown to effect the direct desaturation of dioleoyl-lecithin to dilinoleoyl-lecithin In rat liver the desaturase was capable of converting 2-eicosatrienoyl-lecithin to 2-arachidonoyl-lecithin Both systems required reduced pyridine nucleotides, O2 and cytochrome b5 Eicosatrienoyl-lecithin desaturase along with eicosatrienoyl-CoA desaturase of rat liver microsomes was solubilized with detergents and purified 7–8-fold from the microsomal pellets Both activities were reconstituted in the presence of deoxycholate on addition of the other components of the cytochrome b5-electron transport chain (cytochrome b5 and NADH-cytochrome b5 reductase) to the solubilized desaturase; addition of lecithin further stimulated the activities The demonstration of desaturation of eicosatrienoyl-lecithin by a solubilized and partially purified desaturase provides strong evidence for the direct desaturation of the lecithin substrate without prior conversion to the acyl-CoA thiolester

Neonatal lupus erythematosus progressing into systemic lupus erythematosus. A 15 year follow-up.

Abstract: SUMMARY An infant with neonatal lupus erythematosus developed systemic lupus erythematosus at the age of 13. The clinical distinction between neonatal lupus erythematosus and familial lupus erythematosus may not be as clear cut as previously reported.

Talking yourself out of pain: The importance of believing that you can

Abstract: The role of believing in the efficacy of a self-control response in coping with pain was investigated in 70 subjects who underwent a pretest-posttest cold pressor test. Forty self-statement trained subjects received either (1)the Stress Inoculation Training rationale while hypnotized, (2)the rationale while “awake,” (3)a hypnotic induction only, or (4)simple instructions to repeat the self-statements before posttesting. Three other groups were used to control for self-statements training, hypnosis, and task-motivational instructions. The results showed that subjects provided with the rationale coped better than subjects who were simply instructed to repeat self-statements as a task demand of the experiment. The hypnosis manipulation results were consistent with the hypothesis that expectations and beliefs about a self-control response may be at the heart of what makes Stress Inoculation Training effective. The relation between believing in the efficacy of a self-control response and believing in the semantic meaning of the self-statements was discussed.

Improved Yields of Factor VIII from Heparinized Plasma

Abstract: The Factor VIII procoagulant activity in plasma, cryoprecipitate, and their polyethylene glycol (PEG) precipitates is markedly increased if blood is collected into heparin rather than into citrate phosphate dextrose (CPD). There is a 34% increase in the initial level of the Factor VIII activity in the heparinized plasma with 78% of this initial activity (184 U) recovered in the cryoprecipitated. As well, the stability of the Factor VIII activity is improved: after 24 h of incubation at 22 degrees C, 99% of the initial activity is retained in heparinized plasma whereas only 64% remains in CPD plasma. The cryoprecipitate prepared from heparinized plasma is equally stable after 24 h. The PEG concentrate prepared from the cryoprecipitate of heparinized plasma is increased to 128 U compared to only 54 U from CPD plasma. Relative recoveries were 531 U/l for heparinized plasma versus 215 U/l for CPD plasma. This represents a 147% increase in yield.

On Being the Offspring of an Alcoholic: An Update

Abstract: Reporting on research advances in a previous review of the literature, this article discusses the relative lack of controlled and prospective studies, the need for more treatment resources, the vulnerability of children of alcoholic parents compared to those of parents with other psychiatric diagnoses, and speculates on the sources of strength of the competent child of alcoholic parents.

Single pulse stimulation of guinea-pig vas deferens and the presynaptic receptor hypothesis.

Abstract: 1 The effect of phenoxybenzamine on the efflux of [3H]-noradrenaline and the mechanical response to single pulse excitation of superfused guinea-pig vas deferens was determined to examine the validity of the currently accepted hypothesis of a presynaptic negative feedback system on adrenergic nerve terminals. 2 The adrenoceptor antagonist enhanced both the outflow of tritium and the mechanical response to single pulse stimulation. The efflux of labelled material and the responses to 4 pulses were also enhanced, as expected. 3 Blockade of neuronal and extraneuronal uptake did not by itself increase nerve-induced outflow or the mechanical response nor dated within the framework of a hypothesis that proposes that the enhancement of response and tritium efflux by phenoxybenzamine results from blockade of a feedback system whereby noradrenaline released by previous impulses inhibits its own subsequent release.

Reversal potential for noradrenaline-induced hyperpolarization of spinal motoneurons.

Abstract: By using two separate electrodes with tips inside a single feline motoneuron, current-voltage characteristics were studied during extracellular iontophoresis of noradrenaline. The usually observed hyperpolarization was accompanied by an increase in membrane resistance and became larger with polarizing and smaller with depolarizing currents. During large depolarizing current injections, the noradrenaline-induced potential reversed its direction, usually at a membrane potential of about -20 millivolts. These data are compatible with the concept that noradrenaline hyperpolarizes nerve cells by decreasing resting membrane conductances to sodium and potassium ions. The observation could also be explained by a nonspecific decrease in ion permeability that is associated with a hyperpolarization due to sodium pump activation.