Showing papers by "Université de Sherbrooke published in 1983"
258 citations
TL;DR: In this article, measurements were made of the two-dimensional flow and temperature field in a dc plasma jet under different operating conditions and the particle velocity and the in-flight particle temperature were also measured for narrow cuts of alumina powders, of mean particle diameters of 18, 23, 39 and 46 mum, injected in the jet.
Abstract: Measurements were made of the two-dimensional flow and temperature field in a dc plasma jet under different operating conditions The particle velocity and the in-flight particle temperature were also measured for narrow cuts of alumina powders, of mean particle diameters of 18, 23, 39 and 46 mum, injected in the jet The results are compared with the predictions of a one-dimensional mathematical model The measured and computed particle velocities are in good agreement This is, however, not the case for the particle temperature where considerable differences are observed An attempt is made to determine the parameters which are often unduly neglected in modelling work and to identify the areas where further work is needed
173 citations
TL;DR: In this article, a theoretical analysis was made of the different phenomena encountered and the assumptions involved in the calculation of the heat transfer rate to a single sphere under plasma conditions, and it was shown that if the integral mean thermal conductivity of the plasma is used in the evaluation of heat transfer coefficient, the Nusselt number for the conduction heat transfer between the plasma and the particle is equal to 2.0.
152 citations
TL;DR: The relative potencies of C-terminal fragments of CCK-8(SO3H), benzotript and proglumide in inhibiting specific [3H]pentagastrin binding to CCK brain receptors reinforce the concept of different brain and pancreas CCK receptors.
128 citations
TL;DR: Proteins in samples containing up to at least 60% Percoll can be accurately quantitated on a standard curve prepared in the absence of Percoll, and the sensitivity of the assay was better than 100 ng.
91 citations
TL;DR: The existence of a high risk of large bowel cancer in a group of workers in a synthetic fiber factory is confirmed and other factors antecedent toLarge bowel cancer are suggested.
Abstract: Two hundred and seven large bowel cancer patients (93% of all cases diagnosed in a defined community between 1965 and 1976) were matched at random with non-cancer subjects of same age, sex, and place of residence. Men with cancer, aged 75 years and younger than, had a more frequent history of work in a local factory handling synthetic fiber than controls (22 versus 10; P less than 0.025). In this factory 45% of cancers occurred before age 60, while this was true in only 24% of cancer cases outside the factory (P less than 0.05). There was a greater tendency for cancers in factory workers to occur in the colon than in the rectum. Heredity was not found to be a risk factor for large bowel cancer. The rate of prior appendectomy was higher in men with colon cancer (P less than 0.05) and the rate of prior cholecystectomy was lower in females with colonic cancer (P less than 0.05). A previous hemorroidectomy was also found more often in males with colonic cancer (P less than 0.05). Long-standing severe constipation was present more often in patients with cancer (P less than 0.01). There was some evidence for a compounding influence of different risk factors, as studied by relative risk ratio. This study confirms the existence of a high risk of large bowel cancer in a group of workers in a synthetic fiber factory and suggests other factors antecedent to large bowel cancer.
82 citations
TL;DR: The colonic myoelectric spiking activity was recorded in 10 healthy subjects using an intraluminal tube equipped with four bipolar Ag-AgCl ring electrodes fixed 10 cm apart using a probe introduced into the sigmoid colon by endoscopy.
73 citations
TL;DR: The temperature-sensitive adenovirus type 2 mutant H2ts1 is defective for polypeptide processing at the non-permissive temperature is mapped by marker rescue and DNA sequencing techniques: the mutation is a C/T transition located at map co-ordinate 61.1.
68 citations
TL;DR: The quantitative analysis of 67Ga lung uptake in normal subjects and patients with various pulmonary diseases provides an objective index of inflammatory activity in lung tissues, and it is simple, sensitive, and discriminative.
59 citations
TL;DR: Results revealed that neurotensin significantly increased the hypothermia induced by apomorphine and N-n-propylnorapomorphine, and possible mechanisms which could underly neurotens in's selective inhibitory action on hyperactivity produced by both pre and post synaptic dopaminergic stimulation are discussed.
54 citations
TL;DR: In this article, a flow visualization has indicated the mean flow patterns around 2-D rectangular cylinders exposed to smooth flow and the loci of formation of the wake vortices and the presence of a bubble of separation on the cylinders' side wall.
TL;DR: In this article, the densities and volumetric heat capacities of urea and alcohols were measured in aqueous solutions of octylammonium bromide (OABr) and of OABr-H2O.
Abstract: The densities and volumetric heat capacities of urea and alcohols were measured in aqueous solutions of octylammonium bromide (OABr) and of OABr in aqueous urea and alcohol solutions. The alcohols studies were methanol, ethanol, 1-propanol, 2-propanol, n-butanol, t-butanol, n-pentanol, n-hexanol and 2-butoxyethanol (BE). In most experiments, the concentration of the reference solute was kept low, and volumes and heat capacities of transfer from water to the mixed solvent were calculated. A more complete study was made with the system BE-OABr-H2O where both solutes were systematically changed. The observed trends in the thermodynamic functions can be explained through three effects: interactions between the reference solute and the cosolvent in the premiceller region of the surfactant or pre-aggregation region of the alcohol, a distribution of the reference solute between water and the micelle or microphase and an equilibrium displacement of the system, monomer-aggregate, in the vicinity of the reference solute.
TL;DR: The extracellular patch-clamp technique was used to investigate the presence of ionic channels in HeLa cells, a well-known cultured cell type obtained from an epidermoid carcinoma of the cervix, and it was revealed that the probability of the channel to be in the open state was a function of the KCl concentration in the patch pipette.
Abstract: The extracellular patch-clamp technique was used in order to investigate the presence of ionic channels in HeLa cells, a well-known cultured cell type obtained from an epidermoid carcinoma of the cervix. Under Gigohm-seal conditions, discrete current jumps could be observed with patch electrodes containing KCl. These channels were found to be mainly permeable to K+ and showed multiple levels of conductance. From single-channelI–V curve measurements, a strong rectification effect, characterized by a large inward and no detectable outward current, was observed. For negative membrane potentials (0 to −90 mV), the measured current-voltage relationship was found to be mostly linear, corresponding to a single-channel conductance of 40 pS. An analysis of some selected time records has revealed in addition that the probability of the channel to be in the open state was a function of the KCl concentration in the patch pipette.
TL;DR: The results support the use of ceftazidime as single-drug treatment of hospitalized patients with pneumonia and show no differences between the two groups: the same is true for bacteriological response.
Abstract: A multicentre prospective randomized control trial was done to compare the efficacy and toxicity of ceftazidime with that of cefazolin/tobramycin in the treatment of hospitalized patients with non-pneumococcal pneumonia. The results for 50 patients are reported in this paper; 24 in the ceftazidime group and 26 in the cefazolin/tobramycin group. Measurements of clinical response show no differences between the two groups: the same is true for bacteriological response. Minimal toxicity was seen with both treatment groups. The results support the use of ceftazidime as single-drug treatment of hospitalized patients with pneumonia.
TL;DR: In this paper, exact real-space rescaling transformations are used to calculate the spectral properties of tight-binding Hamiltonians with arbitrary range of interaction on a linear chain, and the singularities of the spectral functions within the band of extended states are associated with fixed points of the rescaling transformation.
Abstract: Exact real-space rescaling transformations are used to calculate the spectral properties of tight-binding Hamiltonians with arbitrary range of interaction on a linear chain. Singularities of the spectral functions within the band of extended states are associated with fixed points of the rescaling transformation. The fixed points separate regions of energy in which the behavior of the system is qualitatively different. The method is not restricted to one dimension and can also be used to treat single-impurity problems.
TL;DR: The existence of at least two distinct pools of secretory proteins in the exocrine pancreas are confirmed and the existence of an intracellular route ofsecretory proteins which would bypass the zymogen granule compartment is suggested.
TL;DR: In this article, an experimental testing rig capable of subjecting thin-walled tubes to combined dynamic loadings in tension-compression with torsion and tension compression with internal-external pressure is presented.
Abstract: It is well know that high-strain biaxial testing with axial force and pressure on thin-walled tubes can be interesting from several points of view: capability of testing over the whole range of strain or stress ratios, great versatility of testing. and because of the physical system, the measured strains and stresses are principal. Nevertheless, there are few experimental-biaxial-fatique data due to the complexity of the testing equipment involved. In this paper, an experimental testing rig capable of subjecting thin-walled tubes to combined dynamic loadings in tension-compression with torsion and tension-compression with internal-external pressure is presented. The following components are described: the mechanical and hydraulic system, servohydraulic control, specimen configuration, strain-measuring equipment and data-acquisition system. The computation of stresses and strains, as well as examples of data acquisition, are also shown.
TL;DR: Results are consistent with a sequential hydrolysis of the two diphosphoester bonds of ATP: ATP first binds to the enzyme, its γ-phosphate group is hydrolyzed and released, resulting in an enzyme-ADP complex which either breaks down to free enzyme and ADP or is further processed via hydrolytic of the β-ph phosphate group, releasing free enzyme, AMP and Pi.
TL;DR: The results show that the morphological as well as the functional integrity of the mucosa is preserved for at least 48 h when small intestine of suckling mice is cultured in a serum-free medium.
Abstract: Proximal and distal parts of the small intestine of 8-day-old suckling mice can best be maintained for 48 h in a serum-free organ culture system, Leibovitz L-15, at room air and room temperature. As determined by light and electron microscopy, the villous architecture was preserved as well as the classical ultrastructure of the enterocytes. Incorporation of 3H-thymidine and 3H-leucine continued during the culture period, reflecting a sustained synthesis of DNA and proteins for at least 48 h. The hydrolytic activities of the brushborder membrane, namely of lactase (L), trehalase (T), glucoamylase (GA) and alkaline phosphatase (AlPase) were measured in the explants as well as the culture medium. The overall enzymatic activities were increased as compared to the controls. In the tissue, L, GA and T activities remained stable or even increased during culture while in the medium an accumulation of enzymatic activities was noted especially for GA an AlPase. These results show that the morphological as well as the functional integrity of the mucosa is preserved for at least 48 h when small intestine of suckling mice is cultured in a serum-free medium.
TL;DR: In this paper, phase diagrams of microemulsions using 2-butoxyethanol (BE) and diethylmethylamine (Et2McN) in water suggest that these two liquids could be more effective cosurfactants than the usual alcohols used for this purpose.
Abstract: For oil sand extractions with microemulsions it is important to disperse large quantities of light hydrocarbons in an aqueous medium. Fundamental studies on the properties of 2-butoxyethanol (BE) and diethylmethylamine (Et2McN) in water suggest that these two liquids could be more effective cosurfactants than the usual alcohols used for this purpose. The phase diagrams of microemulsions using BE and Et2MeN as cosurfactants, combined with typical ionic and non-ionic surfactants and typical aliphatic and aromatic hydrocarbons, were therefore investigated and compared with microemulsions based on n-butanol. Although the phase diagrams depend significantly on the nature of the surfactant and of the oil, the monophasic region generally increases with the cosurfactant in the order n-butanol < Et2McN < BE. With the active mixture BE-cetyltrimethylammonium bromide, temperature has little effect on the phase diagram and NaCl generally destabilizes the microemulsion.
Pour extraire les sables bitumineux avec des microemulsions, il est important de disperser de grandes quantites d'hydrocarbures legers dans un milieu aqueux. Des etudes fondamentales sur les proprietes du 2-butoxyethanol (BE) et de la diethylmethylamine (Et2MeN) dans l'eau suggerent que ces deux liquides pourraient e'tre des cotensioactifs plus efficaces que les alcools simples utilises normalement dans ce but. Les diagrammes de phase utilisant BE et Et2MeN comme cotensioactifs, combines avec des tensioactifs ioniques et non-ioniques et des hydrocarbures aliphatiques et aromatiques typiques, ont donc ete etudies et compares avec ceux des microemulsions basees sur le n-butanol. Meme si les diagrammes de phase dependent beaucoup de la nature du tensioactif et de l'hydrocarbure, la region monophasique augmente generalement avec le cotensioactif dans l'ordre n-butanol < Et2MeN < BE. Avec le melange actif BE-bromure de cetyltrimethylammonium, la temperature a peu d'effct sur le diagramme de phase et NaCl destabilise generalement la microemulsion.
TL;DR: Bronchoalveolar lavage revealed normal cell differential counts in the right middle lobe of each patient, but high-intensity lymphocytic alveolitis in theright upper lobe, suggesting that BAL should be done in multiple segments of the lung to obtain a truly representative picture of the intensity of the alveolidis in stage III pulmonary sarcoidosis.
TL;DR: In this paper, it is shown that the analogy between the free energy in critical phenomena and the complex generating function allows one to exploit well known position-space renormalization group techniques to easily derive scaling properties as well as the exact density of states for electronic or vibrational problems on fractal lattices.
Abstract: It is shown that the analogy between the free energy in critical phenomena and the complex generating function allows one to exploit well known position-space renormalization group techniques to easily derive scaling properties as well as the exact density of states for electronic or vibrational problems on fractal lattices. Certain self-similar lattices whose spectral dimension d~ can be larger or less than 2 are also studied L'analogie entre energie libre des phenomenes critiques et la fonction generatrice complexe permet l'utilisation des techniques du groupe de renormalisation dans l'espace direct pour etablir les proprietes d'echelle et la densite d'etats exacte pour les problemes electroniques ou de vibration sur des reseaux fractals. Discussion de l'existence d'une famille de reseaux dont la dimension spectrale d~ peut etre inferieure ou superieure a 2
TL;DR: The results rule out the hypothesis that the Lyt-3 locus itself controls the light chain phenotype observed in normal serum immunoglobulin, and indicate that recombination between chromosome 6 loci controlling kappa chain expression in normal mouse serum immunglobulin is unlikely.
Abstract: Recombination has been detected for the first time between chromosome 6 loci controlling kappa chain expression in normal mouse serum immunoglobulin and the Lyt-3 locus. The recombination event occurred at the 26th or 27th backcross generation during the derivation of the Lyt-2a, Lyt-3a-congenic line B6.PL(85NS). The line is now homozygous for the Lyt-2a, Lyt-3a allele(s) at N30F13 and homozygous animals express the Igk-Ef1b allele derived from C57BL/6. The frequency of recombination has been estimated to be 0.30% based on the present results and previous studies in which no recombination was detected. The results rule out the hypothesis that the Lyt-3 locus itself controls the light chain phenotype observed in normal serum immunoglobulin.
TL;DR: In AtT-20 cells, inhibition of ACTH secretion may be regulated by activation of muscarinic receptors coupled negatively to adenylate cyclase, and the inhibitory effects of carbachol on (-) isoproterenol-stimulated cyclic AMP synthesis andACTH secretion were reversed by theMuscarinic antagonist, atropine, and not by the nicotinic antagonist, gallamine.
TL;DR: The effects of the prostaglandins seem to be directly myogenic since cholinergic and adrenergic blockers and tetrodotoxin did not affect them.
TL;DR: In the search for a natural, non-estrogenic inhibitor of human placental aromatase, the effect on this enzyme complex of 6 alpha- and 6 beta-OOH-androstenedione, as well as of their corresponding 6-hydroxy and 6-oxo metabolites, is studied.
01 Jan 1983
TL;DR: Organic extracts from MAF and RAF are able to promote villus formation in undifferentiated explants from 15‐day fetal mouse duodenum in organ culture and RAF organic extract contains a factor that can induce the formation of duodenal crypts and the differentiation of Paneth cells in culture at least 2 days before their normal appearance.
Abstract: The effect of acid, basic, and organic extracts from Long Evans rat amniotic fluid (RAF) and from Swiss ICR mouse amniotic fluid (MAF) was studied on 15-day fetal mouse duodenal mucosa in organ culture. Amniotic fluids (20 ml) were lyophilized and extracted 1) with CHCl3:MeOH and the organic phase was evaporated; then 2), the residue was acidified with a solution of 0.1 N HCl in 10% acetic acid and the liquid phase was lyophilized; finally 3), 0.01 M NH4OH was added to the residue and the liquid phase was lyophilized. The product of each extraction was added to 20 ml of Trowell T8 medium. Acid and basic extracts of RAF and MAF have no effect on the formation of duodenal villi and crypts after 48 hours of culture. With the organic extract of MAF, small villi are present after 48 hours of culture and absorptive cells are poorly differentiated. With the organic extract of RAF, well-developed villi have differentiated after 48 hours of culture; moreover, crypts are present at the same stage and Paneth cells are identified within these crypts. During the 8-10 hour period, the explants cultured with the Trowell T8 medium supplemented with RAF or MAF organic extracts show a 35% increase in 3H-thymidine incorporation over the controls cultured with Trowell T8 medium alone. These results indicate that organic extracts from MAF and RAF are able to promote villus formation in undifferentiated explants from 15-day fetal mouse duodenum in organ culture. Furthermore, RAF organic extract contains a factor that can induce the formation of duodenal crypts and the differentiation of Paneth cells in culture at least 2 days before their normal appearance.
TL;DR: In this article, L-Phenylalanine has been treated with chlorosulfonic acid and the resulting sulfonic-acid and aminosulfonyl derivatives have been employed for peptide synthesis with Boc-protection of the Nα-position only.
Abstract: L-Phenylalanine has been treated with chlorosulfonic acid and the product was either hydrolyzed, ammonolyzed or reduced. The resulting sulfonic-acid and aminosulfonyl derivatives have been employed for peptide synthesis with Boc-protection of the Nα-position only. The reduction product L-(4′-SH)Phe has been protected by formation of asymmetric disulfides or with various thiol protecting groups (benzyl-, methyl- and acetamidomethyl groups, the latter being the most suitable for peptide synthesis).
With these protected amino acids several analogues of angiotensin II have been synthesized by the solid-phase method. These analogues have been used for structure-activity relationship studies on three different bioassays.
TL;DR: The results suggest that the shift in the amylase dose-response curve to carbamylcholine, noted following bethanechol treatment in vivo, could be coupled with the observed change in affinity of the two agonist forms of muscarinic receptor in the pancreas.