Institution
Université de Montréal
Education•Montreal, Quebec, Canada•
About: Université de Montréal is a education organization based out in Montreal, Quebec, Canada. It is known for research contribution in the topics: Population & Context (language use). The organization has 45641 authors who have published 100476 publications receiving 4004007 citations. The organization is also known as: University of Montreal & UdeM.
Papers published on a yearly basis
Papers
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TL;DR: It is shown that brushes of charged polymers (polyelectrolytes) attached to surfaces rubbing across an aqueous medium result in superior lubrication compared to other polymeric surfactants.
Abstract: Long-ranged forces between surfaces in a liquid control effects from colloid stability to biolubrication, and can be modified either by steric factors due to flexible polymers, or by surface charge effects. In particular, neutral polymer 'brushes' may lead to a massive reduction in sliding friction between the surfaces to which they are attached, whereas hydrated ions can act as extremely efficient lubricants between sliding charged surfaces. Here we show that brushes of charged polymers (polyelectrolytes) attached to surfaces rubbing across an aqueous medium result in superior lubrication compared to other polymeric surfactants. Effective friction coefficients with polyelectrolyte brushes in water are lower than about 0.0006-0.001 even at low sliding velocities and at pressures of up to several atmospheres (typical of those in living systems). We attribute this to the exceptional resistance to mutual interpenetration displayed by the compressed, counterion-swollen brushes, together with the fluidity of the hydration layers surrounding the charged, rubbing polymer segments. Our findings may have implications for biolubrication effects, which are important in the design of lubricated surfaces in artificial implants, and in understanding frictional processes in biological systems.
781 citations
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Broad Institute1, University of Oxford2, Wellcome Trust Sanger Institute3, Wellcome Trust Centre for Human Genetics4, Utrecht University5, Science Applications International Corporation6, Illumina7, Duke University8, Brigham and Women's Hospital9, University of Cambridge10, Harvard University11, Imperial College London12, Université de Montréal13, Montreal Heart Institute14
TL;DR: The analysis provides informative tag SNPs that capture much of the common variation in the MHC region and that could be used in disease association studies, and it provides new insight into the evolutionary dynamics and ancestral origins of the HLA loci and their haplotypes.
Abstract: The proteins encoded by the classical HLA class I and class II genes in the major histocompatibility complex (MHC) are highly polymorphic and are essential in self versus non-self immune recognition. HLA variation is a crucial determinant of transplant rejection and susceptibility to a large number of infectious and autoimmune diseases. Yet identification of causal variants is problematic owing to linkage disequilibrium that extends across multiple HLA and non-HLA genes in the MHC. We therefore set out to characterize the linkage disequilibrium patterns between the highly polymorphic HLA genes and background variation by typing the classical HLA genes and >7,500 common SNPs and deletion-insertion polymorphisms across four population samples. The analysis provides informative tag SNPs that capture much of the common variation in the MHC region and that could be used in disease association studies, and it provides new insight into the evolutionary dynamics and ancestral origins of the HLA loci and their haplotypes.
780 citations
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TL;DR: It is found that ion conduction involves transitions between two main states, with two and three K+ ions occupying the selectivity filter, respectively; this process is reminiscent of the ‘knock-on’ mechanism proposed by Hodgkin and Keynes in 1955.
Abstract: K+ channels are transmembrane proteins that are essential for the transmission of nerve impulses. The ability of these proteins to conduct K+ ions at levels near the limit of diffusion is traditionally described in terms of concerted mechanisms in which ion-channel attraction and ion-ion repulsion have compensating effects, as several ions are moving simultaneously in single file through the narrow pore. The efficiency of such a mechanism, however, relies on a delicate energy balance-the strong ion-channel attraction must be perfectly counterbalanced by the electrostatic ion-ion repulsion. To elucidate the mechanism of ion conduction at the atomic level, we performed molecular dynamics free energy simulations on the basis of the X-ray structure of the KcsA K+ channel. Here we find that ion conduction involves transitions between two main states, with two and three K+ ions occupying the selectivity filter, respectively; this process is reminiscent of the 'knock-on' mechanism proposed by Hodgkin and Keynes in 1955. The largest free energy barrier is on the order of 2-3 kcal mol-1, implying that the process of ion conduction is limited by diffusion. Ion-ion repulsion, although essential for rapid conduction, is shown to act only at very short distances. The calculations show also that the rapidly conducting pore is selective.
780 citations
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TL;DR: A diagnostic strategy combining clinical assessment, D-dimer, ultrasonography, and lung scan gave a non-invasive diagnosis in the vast majority of outpatients with suspected venous thromboembolism, and appeared to be safe.
779 citations
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TL;DR: Although technically feasible, the laparoscopic Whipple procedure may not improve the postoperatively outcome or shorten the postoperative recovery period.
Abstract: A case of chronic pancreatitis localized in the head of the pancreas with pancreas divisum was treated by laparoscopic pylorus-preserving pancreatoduodenectomy. The laparoscopic technique of resection and reconstruction with a gastrojejunostomy, hepaticojejunostomy, and pancreaticojejunostomy is described. The postoperative period was complicated by a jejunal ulcer and delayed gastric emptying necessitating a prolonged hospitalization and intravenous hyperalimentation. No fistulas occurred, a follow-up CT scan revealed no pancreatic abnormalities, and the patient was discharged in good condition on the 30th postoperative day. Although technically feasible, the laparoscopic Whipple procedure may not improve the postoperative outcome or shorten the postoperative recovery period.
779 citations
Authors
Showing all 45957 results
Name | H-index | Papers | Citations |
---|---|---|---|
Yoshua Bengio | 202 | 1033 | 420313 |
Alan C. Evans | 183 | 866 | 134642 |
Richard H. Friend | 169 | 1182 | 140032 |
Anders Björklund | 165 | 769 | 84268 |
Charles N. Serhan | 158 | 728 | 84810 |
Fernando Rivadeneira | 146 | 628 | 86582 |
C. Dallapiccola | 136 | 1717 | 101947 |
Michael J. Meaney | 136 | 604 | 81128 |
Claude Leroy | 135 | 1170 | 88604 |
Georges Azuelos | 134 | 1294 | 90690 |
Phillip Gutierrez | 133 | 1391 | 96205 |
Danny Miller | 133 | 512 | 71238 |
Henry T. Lynch | 133 | 925 | 86270 |
Stanley Nattel | 132 | 778 | 65700 |
Lucie Gauthier | 132 | 679 | 64794 |