Institution
University of Calgary
Education•Calgary, Alberta, Canada•
About: University of Calgary is a education organization based out in Calgary, Alberta, Canada. It is known for research contribution in the topics: Population & Health care. The organization has 44284 authors who have published 104970 publications receiving 3669161 citations. The organization is also known as: U of C & UCalgary.
Papers published on a yearly basis
Papers
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TL;DR: It is shown that the nature of interactions through quorum-sensing chemicals does not simply involve cooperative signals, but entails other interactions such as cues and chemical manipulations that might have a role in conflicts within and between species.
Abstract: Individual bacteria can alter their behaviour through chemical interactions between organisms in microbial communities - this is generally referred to as quorum sensing. Frequently, these interactions are interpreted in terms of communication to mediate coordinated, multicellular behaviour. We show that the nature of interactions through quorum-sensing chemicals does not simply involve cooperative signals, but entails other interactions such as cues and chemical manipulations. These signals might have a role in conflicts within and between species. The nature of the chemical interaction is important to take into account when studying why and how bacteria react to the chemical substances that are produced by other bacteria.
753 citations
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01 Jan 2017TL;DR: In this paper, the authors propose two multi-trip vehicle routing problems (VRPs) specifically for drone delivery scenarios, one minimizes costs subject to a delivery time limit, while the other minimizes the overall delivery time subject to budget constraint.
Abstract: Unmanned aerial vehicles, or drones, have the potential to significantly reduce the cost and time of making last-mile deliveries and responding to emergencies. Despite this potential, little work has gone into developing vehicle routing problems (VRPs) specifically for drone delivery scenarios. Existing VRPs are insufficient for planning drone deliveries: either multiple trips to the depot are not permitted, leading to solutions with excess drones, or the effect of battery and payload weight on energy consumption is not considered, leading to costly or infeasible routes. We propose two multitrip VRPs for drone delivery that address both issues. One minimizes costs subject to a delivery time limit, while the other minimizes the overall delivery time subject to a budget constraint. We mathematically derive and experimentally validate an energy consumption model for multirotor drones, demonstrating that energy consumption varies approximately linearly with payload and battery weight. We use this approximation to derive mixed integer linear programs for our VRPs. We propose a cost function that considers our energy consumption model and drone reuse, and apply it in a simulated annealing (SA) heuristic for finding suboptimal solutions to practical scenarios. To assist drone delivery practitioners with balancing cost and delivery time, the SA heuristic is used to show that the minimum cost has an inverse exponential relationship with the delivery time limit, and the minimum overall delivery time has an inverse exponential relationship with the budget. Numerical results confirm the importance of reusing drones and optimizing battery size in drone delivery VRPs.
752 citations
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INAF1, University of Colorado Boulder2, University College London3, University of Toulouse4, University of Toronto5, Liverpool John Moores University6, California Institute of Technology7, University of Calgary8, European Southern Observatory9, University of Provence10, University of Paris-Sud11, Paris Diderot University12, Katholieke Universiteit Leuven13, University of Bordeaux14, University of Exeter15, University of New South Wales16, University of Leeds17, Spanish National Research Council18, Sapienza University of Rome19, University of Rome Tor Vergata20, Nagoya University21, University of Manchester22, University of Paris23, Jet Propulsion Laboratory24, Cardiff University25, Chinese Academy of Sciences26, Laval University27, University of Helsinki28, Harvard University29, Max Planck Society30, University of Hertfordshire31, University of Cologne32, University of Kent33, Open University34
TL;DR: In this paper, the first results from the science demonstration phase for the Hi-GAL survey, the Herschel key program that will map the inner Galactic plane of the Milky Way in 5 bands, were presented.
Abstract: We present the first results from the science demonstration phase for the Hi-GAL survey, the Herschel key program that will map the inner Galactic plane of the Milky Way in 5 bands. We outline our data reduction strategy and present some science highlights on the two observed 2° × 2° tiles approximately centered at l = 30° and l = 59°. The two regions are extremely rich in intense and highly structured extended emission which shows a widespread organization in filaments. Source SEDs can be built for hundreds of objects in the two fields, and physical parameters can be extracted, for a good fraction of them where the distance could be estimated. The compact sources (which we will call cores' in the following) are found for the most part to be associated with the filaments, and the relationship to the local beam-averaged column density of the filament itself shows that a core seems to appear when a threshold around AV ~ 1 is exceeded for the regions in the l = 59° field; a AV value between 5 and 10 is found for the l = 30° field, likely due to the relatively higher distances of the sources. This outlines an exciting scenario where diffuse clouds first collapse into filaments, which later fragment to cores where the column density has reached a critical level. In spite of core L/M ratios being well in excess of a few for many sources, we find core surface densities between 0.03 and 0.5 g cm-2. Our results are in good agreement with recent MHD numerical simulations of filaments forming from large-scale converging flows.
752 citations
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Newcastle University1, J. Craig Venter Institute2, University of Maryland, College Park3, University of Glasgow4, Technical University of Denmark5, University of Calgary6, Natural History Museum7, Ghent University8, University of Dundee9, University of Sassari10, University of California, Los Angeles11, Children's Hospital Oakland Research Institute12, Charles University in Prague13, University of Iowa14, University of Düsseldorf15, University of California, San Francisco16, University of Queensland17, QIMR Berghofer Medical Research Institute18, Chang Gung University19, University of Strathclyde20
TL;DR: The genome sequence of the protist Trichomonas vaginalis predicts previously unknown functions for the hydrogenosome, which support a common evolutionary origin of this unusual organelle with mitochondria.
Abstract: We describe the genome sequence of the protist Trichomonas vaginalis, a sexually transmitted human pathogen. Repeats and transposable elements comprise about two-thirds of the similar to 160-megabase genome, reflecting a recent massive expansion of genetic material. This expansion, in conjunction with the shaping of metabolic pathways that likely transpired through lateral gene transfer from bacteria, and amplification of specific gene families implicated in pathogenesis and phagocytosis of host proteins may exemplify adaptations of the parasite during its transition to a urogenital environment. The genome sequence predicts previously unknown functions for the hydrogenosome, which support a common evolutionary origin of this unusual organelle with mitochondria.
751 citations
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TL;DR: ASPECTS is a systematic, robust, and practical method that can be applied to different axial baselines and clinician agreement is superior to that of the 1/3 MCA rule.
Abstract: BACKGROUND AND PURPOSE: Clinicians are insecure reading CT scans by using the one-third rule for acute middle cerebral artery stroke (1/3 MCA rule) before treating patients with recombinant tissue plasminogen activator. The 1/3 MCA rule is a poorly defined volumetric estimate of the size of cerebral infarction of the MCA. A 10-point quantitative topographic CT scan score, the Alberta Stroke Program Early CT Score (ASPECTS), is described and illustrated. A sharp increase in dependence and death occurs with an ASPECTS of 7 or less. We describe how to use ASPECTS and why it works with CT scans obtained on all commonly used axial baselines. We also describe interobserver reliability among clinicians from different specialties and with different experience in reading CT scans in the context of acute stroke. METHODS: The six physicians who developed ASPECTS answered a questionnaire on precisely how they interpret and use ASPECTS. The ASPECTS areas as interpreted by these physicians were compared with one another and with standards in the literature. κ statistics were used to assess the interobserver reliability of ASPECTS versus the 1/3 MCA rule. RESULTS: The exact methods of interpretation varied among the six individual observers, with either a 3:3 or 4:2 split on the specific questions. The overall interobserver agreement was good compared with that of the 1/3 MCA rule. Normal anatomic vascular and interobserver variations explain why ASPECTS can be applied with different CT axial baselines. CONCLUSION: ASPECTS is a systematic, robust, and practical method that can be applied to different axial baselines. Clinician agreement is superior to that of the 1/3 MCA rule.
750 citations
Authors
Showing all 44775 results
Name | H-index | Papers | Citations |
---|---|---|---|
Meir J. Stampfer | 277 | 1414 | 283776 |
Zena Werb | 168 | 473 | 122629 |
William J. Sandborn | 162 | 1317 | 108564 |
Gregg C. Fonarow | 161 | 1676 | 126516 |
David W. Johnson | 160 | 2714 | 140778 |
Jerome I. Rotter | 156 | 1071 | 116296 |
Carl Nathan | 135 | 430 | 91535 |
Severine Vermeire | 134 | 1086 | 76352 |
Ian Ford | 134 | 678 | 85769 |
Jeffery D. Molkentin | 131 | 482 | 61594 |
Joseph P. Broderick | 130 | 504 | 72779 |
Shuai Liu | 129 | 1095 | 80823 |
Marcello Tonelli | 128 | 701 | 115576 |
Gary C. Curhan | 128 | 435 | 55348 |
James C. Paulson | 126 | 443 | 52152 |