8,543 research outputs found
Smelling out predators is innate in birds
The role of olfaction for predation risk assessment remains barely explored in birds, although predator chemical cues could be useful in predator detection under low visibility conditions for many bird species. We examine whether Great Tits Parus major are able to use the odour of mustelids to assess predation risk when selecting cavities for roosting. We analysed whether the response to predator chemical cues is innate and assessed whether the antipredatory response is associated with exploratory behaviour, a proxy for the personality of birds. In a choice experiment in aviaries, we offered naïve adult Great Tits of known personality two nest-boxes, one control and one experimental. The experimental nest-box had the odour of a mustelid predator or a strong new odour without biological significance, the control nest-box contained no odour. When one of the cavities contained the odour of a predator, birds avoided the use of either of the two offered nest-boxes, whereas there was no avoidance of boxes when one of the nest-boxes contained a control odour. There was no relationship with exploratory behaviour. We show that the ability to use the chemical cues of predators is innate in birds, but individual differences in the response to predator chemical cues cannot be explained by the personality of the bird.
System Level Synthesis via Dynamic Programming
System Level Synthesis (SLS) parametrization facilitates controller synthesis
for large, complex, and distributed systems by incorporating system level
constraints (SLCs) into a convex SLS problem and mapping its solution to stable
controller design. Solving the SLS problem at scale efficiently is challenging,
and current attempts take advantage of special system or controller structures
to speed up the computation in parallel. However, those methods do not
generalize as they rely on the specific system/controller properties.
We argue that it is possible to solve general SLS problems more efficiently
by exploiting the structure of SLS constraints. In particular, we derive
dynamic programming (DP) algorithms to solve SLS problems. In addition to the
plain SLS without any SLCs, we extend DP to tackle infinite horizon SLS
approximation and entrywise linear constraints, which form a superclass of the
locality constraints. Comparing to convex program solver and naive analytical
derivation, DP solves SLS 4 to 12 times faster and scales with little
computation overhead. We also quantize the cost of synthesizing a controller
that stabilizes the system in a finite horizon through simulations
Results on CP violation and CKM UT angles from Belle and BaBar
We report recent results on CP violation measurements from the two B-factory
experiments, Belle and BaBar.Comment: 4 pages, 4 figures, appeared in the proceedings of the IX
International Conference on Hyperons, Charm and Beauty Hadrons (BEACH 2010),
June 21-26, 2010, Perugia, Ital
Rhodium and copper 6-methylpicolinate complexes. Structural diversity and supramolecular interaction study
Seven new coordination compounds with 6-methylpicolinic acid (6-HMepic) and rhodium(III) or copper(II) of formula [Rh(6-Mepic)3] (1), [Rh(6-Mepic)2(H2O)Cl] (2), [Rh(6-HMepic)(6-Mepic)Cl2]·3.5(H2O) (3), [Cu(6-Mepic)2(H2O)]·H2O (4), [Cu(6-Mepic)2]n, (5), [Cu(6-Mepic)(6-HMepic)I] (6) and [Cu(6-Mepic)(6-HMepic)Cl] (7) have been obtained. Their syntheses have been rationalized, and their structural and supramolecular characteristics have been studied and compared with other similar rhodium and copper picolinate complexes previously reported, in order to stablish structural correlations and analogies. The electrical properties of coordination polymer [Cu(6-Mepic)2]n (5) have been also analyzed and it has been found that it shows a moderated electrical transport along the chain.We thank the financial support from the Spanish Ministerio de Economía y Competitividad (MAT2013-46502-C2-2P and MAT2013-46753-C2-1P). Also the scientific computing center (CCC) of the Autonoma University of Madrid for their tim
- …