Institution
University of Costa Rica
Education•San José, Costa Rica•
About: University of Costa Rica is a education organization based out in San José, Costa Rica. It is known for research contribution in the topics: Population & Venom. The organization has 9817 authors who have published 16781 publications receiving 238208 citations. The organization is also known as: UCR & Universidad de Costa Rica.
Topics: Population, Venom, Antivenom, Snake venom, Myotoxin
Papers published on a yearly basis
Papers
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TL;DR: A molecular mechanism of action is proposed, which is able to explain the p65 selectivity of the SLs and the observed correlation of high activity with alkylant bifunctionality.
234 citations
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TL;DR: Comparisons of field and laboratory studies will permit a more realistic evaluation of the role of taste and color preferences in food choice by hummingbirds, and a better understanding of the coevolution of hummingbirds and the flowers they pollinate.
Abstract: Taste and color preferences have been experimentally demonstrated for a variety of birds, and the literature on food habits of wild birds is enormous, but as yet there is little to tie the two together. Laboratory experiments have usually involved taste stimuli that are probably irrelevant to birds in the wild; and the taste stimuli presented by insects, seeds, fruit, etc. are complex and difficult to duplicate for experimental purposes. The same is true to a considerable extent of color: the mostly granivorous species studied so far probably never experience bright, monochromatic colors in connection with feeding. Moreover, caloric parameters of birds’ foods are often difficult to measure or estimate but will almost certainly affect food selection, making taste and color preferences harder to assess. Hummingbirds are ideal subjects in studies of taste and color preferences. Their main foods are nectar and insects; flowers are visited almost exclusively for nectar, insects being captured elsewhere. Flower nectar is essentially an aqueous solution of 3 common sugars (Percival 1961, see also beyond). It can be easily sampled and its concentration, caloric value, and composition measured. The taste stimuli can be readily duplicated and manipulated experimentally. Assimilation of flower nectar is essentially 100% (Hainsworth 1974) making caloric parameters easy to estimate. Flowers visited by hummingbirds are usually brightly colored and fairly unpatterned, also favoring experimentation. The long controversy over the existence of color preferences in hummingbirds was reviewed by Grant and Grant ( 1968). The roles of color and taste factors have been greatly clarified by the feeding station experiments of Collias and Collias (1968); similar experiments by Miller and Miller (1971) further elucidated the role of position. These studies suggest a hierarchy of factors influencing feeder choice: sugar concentration and/or taste over position over color. As yet this hierarchy has not been subjected to experimental verification, or applied in detail to flower choice in the field. This paper presents laboratory experiments on taste and color preferences of the Anna Hummingbird (Calypte anna) and several other species. I also present the results of extensive field observations on flower choice by hummingbirds, and consider the taste and color stimuli presented by those flowers visited by hummingbirds. Hopefully, comparing the results of field and laboratory studies will permit a more realistic evaluation of the role of taste and color preferences in food choice by hummingbirds, and a better understanding of the coevolution of hummingbirds and the flowers they pollinate.
233 citations
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17 Jul 2017TL;DR: A usability test of the most prestigious and internationally used Speech-based NUI (i.e., Alexa, Siri, Cortana and Google’s) shows that even though there are many services available, there is a lot to do to improve the usability of these systems.
Abstract: Natural User Interfaces (NUI) are supposed to be used by humans in a very logic way. However, the run to deploy Speech-based NUIs by the industry has had a large impact on the naturality of such interfaces. This paper presents a usability test of the most prestigious and internationally used Speech-based NUI (i.e., Alexa, Siri, Cortana and Google’s). A comparison of the services that each one provides was also performed considering: access to music services, agenda, news, weather, To-Do lists and maps or directions, among others. The test was design by two Human Computer Interaction experts and executed by eight persons. Results show that even though there are many services available, there is a lot to do to improve the usability of these systems. Specially focused on separating the traditional use of computers (based on applications that require parameters to function) and to get closer to real NUIs.
231 citations
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Great Lakes Bioenergy Research Center1, Smithsonian Tropical Research Institute2, University of Wisconsin-Madison3, Joint Genome Institute4, University of Costa Rica5, Michigan State University6, United States Department of Agriculture7, Los Alamos National Laboratory8, Hoffmann-La Roche9, Roche Applied Science10
TL;DR: It is revealed that the fungus garden microbiome of leaf-cutter ants is composed of a diverse community of bacteria with high plant biomass-degrading capacity, indicating evolutionary convergence of plant biomass degrading potential between two important herbivorous animals.
Abstract: Herbivores can gain indirect access to recalcitrant carbon present in plant cell walls through symbiotic associations with lignocellulolytic microbes. A paradigmatic example is the leaf-cutter ant (Tribe: Attini), which uses fresh leaves to cultivate a fungus for food in specialized gardens. Using a combination of sugar composition analyses, metagenomics, and whole-genome sequencing, we reveal that the fungus garden microbiome of leaf-cutter ants is composed of a diverse community of bacteria with high plant biomass-degrading capacity. Comparison of this microbiome's predicted carbohydrate-degrading enzyme profile with other metagenomes shows closest similarity to the bovine rumen, indicating evolutionary convergence of plant biomass degrading potential between two important herbivorous animals. Genomic and physiological characterization of two dominant bacteria in the fungus garden microbiome provides evidence of their capacity to degrade cellulose. Given the recent interest in cellulosic biofuels, understanding how large-scale and rapid plant biomass degradation occurs in a highly evolved insect herbivore is of particular relevance for bioenergy.
225 citations
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TL;DR: In this paper, the authors derived the power behavior of light-front Fock-state hadronic wavefunctions for hard scattering in the large-r region of the AdS space from the conformal isometries which determine the scaling of string states as we approach the boundary from the interior of AdS. The nonperturbative scaling results were obtained for spin-zero and spin-1/2 hadrons and extended to include the orbital angular momentum dependence of the constituents in the Fockexpansion in the light-cone.
224 citations
Authors
Showing all 9922 results
Name | H-index | Papers | Citations |
---|---|---|---|
Alberto Ascherio | 136 | 462 | 69578 |
Gervasio Gomez | 133 | 1844 | 99695 |
Myron M. Levine | 123 | 789 | 60865 |
Hong-Cai Zhou | 114 | 489 | 66320 |
Edward O. Wilson | 101 | 406 | 89994 |
Mary Claire King | 100 | 336 | 47454 |
Olga Martín-Belloso | 86 | 384 | 23428 |
José María Gutiérrez | 84 | 607 | 26779 |
Cesare Montecucco | 84 | 382 | 27738 |
Rodolphe Clérac | 78 | 506 | 22604 |
Kim R. Dunbar | 74 | 470 | 20262 |
Paul J. Hanson | 70 | 251 | 19504 |
Hannia Campos | 69 | 210 | 15164 |
Jean-Pierre Gorvel | 67 | 231 | 15005 |
F. Albert Cotton | 66 | 1023 | 27647 |