| 1. |
- Garibaldi, Lucas A., et al.
(author)
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Wild Pollinators Enhance Fruit Set of Crops Regardless of Honey Bee Abundance
- 2013
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In: Science. - : American Association for the Advancement of Science (AAAS). - 0036-8075 .- 1095-9203. ; 339:6127, s. 1608-1611
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Journal article (peer-reviewed)abstract
- The diversity and abundance of wild insect pollinators have declined in many agricultural landscapes. Whether such declines reduce crop yields, or are mitigated by managed pollinators such as honey bees, is unclear. We found universally positive associations of fruit set with flower visitation by wild insects in 41 crop systems worldwide. In contrast, fruit set increased significantly with flower visitation by honey bees in only 14% of the systems surveyed. Overall, wild insects pollinated crops more effectively; an increase in wild insect visitation enhanced fruit set by twice as much as an equivalent increase in honey bee visitation. Visitation by wild insects and honey bees promoted fruit set independently, so pollination by managed honey bees supplemented, rather than substituted for, pollination by wild insects. Our results suggest that new practices for integrated management of both honey bees and diverse wild insect assemblages will enhance global crop yields.
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| 2. |
- Kennedy, Christina M., et al.
(author)
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A global quantitative synthesis of local and landscape effects on wild bee pollinators in agroecosystems
- 2013
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In: Ecology Letters. - : Wiley. - 1461-023X .- 1461-0248. ; 16:5, s. 584-599
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Journal article (other academic/artistic)abstract
- Bees provide essential pollination services that are potentially affected both by local farm management and the surrounding landscape. To better understand these different factors, we modelled the relative effects of landscape composition (nesting and floral resources within foraging distances), landscape configuration (patch shape, interpatch connectivity and habitat aggregation) and farm management (organic vs. conventional and local-scale field diversity), and their interactions, on wild bee abundance and richness for 39 crop systems globally. Bee abundance and richness were higher in diversified and organic fields and in landscapes comprising more high-quality habitats; bee richness on conventional fields with low diversity benefited most from high-quality surrounding land cover. Landscape configuration effects were weak. Bee responses varied slightly by biome. Our synthesis reveals that pollinator persistence will depend on both the maintenance of high-quality habitats around farms and on local management practices that may offset impacts of intensive monoculture agriculture.
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| 3. |
- Bao, Ling, 1980, et al.
(author)
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M5-branes, toric diagrams and gauge theory duality
- 2012
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In: Journal of High Energy Physics. - 1029-8479 .- 1126-6708. ; 2012:4
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Journal article (peer-reviewed)abstract
- In this article we explore the duality between the low energy effective theory of five-dimensional N = 1 SU(N)(M-1) and SU(M)(N-1) linear quiver gauge theories compactified on S-1. The theories we study are the five-dimensional uplifts of four-dimensional superconformal linear quivers. We study this duality by comparing the Seiberg-Witten curves and the Nekrasov partition functions of the two dual theories. The Seiberg-Witten curves are obtained by minimizing the worldvolume of an M5-brane with nontrivial geometry. Nekrasov partition functions are computed using topological string theory. The result of our study is a map between the gauge theory parameters, i.e., Coulomb moduli, masses and UV coupling constants, of the two dual theories. Apart from the obvious physical interest, this duality also leads to compelling mathematical identities. Through the AGTW conjecture these five-dimentional gauge theories are related to q-deformed Liouville and Toda SCFTs in two-dimensions. The duality we study implies the relations between Liouville and Toda correlation functions through the map we derive.
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| 4. |
- Bao, Ling, 1980, et al.
(author)
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Non-Lagrangian theories from brane junctions
- 2014
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In: Journal of High Energy Physics. - 1029-8479 .- 1126-6708. ; 2014:1, s. Art. no. 175-
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Journal article (peer-reviewed)abstract
- In this article we use 5-brane junctions to study the 5D T N SCFTs corresponding to the 5D N = 1 uplift of the 4D N = 2 strongly coupled gauge theories, which are obtained by compactifying N M5 branes on a sphere with three full punctures. Even though these theories have no Lagrangian description, by using the 5-brane junctions proposed by Benini, Benvenuti and Tachikawa, we are able to derive their Seiberg-Witten curves and Nekrasov partition functions. We cross-check our results with the 5D super-conformal index proposed by Kim, Kim and Lee. Through the AGTW correspondence, we discuss the relations between 5D superconformal indices and n -point functions of the q -deformed W N Toda theories.
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