2,856 research outputs found
A Rotationally Symmetric Lateral Distribution Function for Radio Emission from Inclined Air Showers
Radio detection of inclined air showers is currently receiving great
attention. To exploit the potential, a suitable event reconstruction needs to
be developed. The first step in this direction is the development of a model
for the lateral distribution of the radio signals, which in the case of
inclined air showers exhibits asymmetries due to "early-late" effects in
addition to the usual asymmetries from the superposition of charge-excess and
geomagnetic emission. We present a model which corrects for all asymmetries and
successfully describes the lateral distribution of the energy fluence with a
rotationally symmetric function. This gives access to the radiation energy as a
measure of the energy of the cosmic-ray primary, and is also sensitive to the
depth of the shower maximum.Comment: To be published in the proceedings of the ARENA2018 conference;
revised version with important fix of former equation (2
Sperm competition affects sex allocation but not sperm morphology in a flatworm
Sperm competition has been shown to be an important evolutionary agent affecting the behaviour, physiology, and morphology of both males and females. One morphological trait that is particularly likely to be affected by sperm competition is sperm size because it is thought to influence the competitiveness of sperm by determining sperm longevity, motility, and/or their ability to displace competing sperm. Most comparative studies across taxa have found a positive relationship between the level of sperm competition and sperm length, but very few studies have tested for a phenotypically plastic adjustment of sperm morphology in response to sperm competition. In this study, we experimentally tested for an effect of sperm competition on phenotypic plasticity in sperm morphology in an obligately outcrossing simultaneous hermaphrodite, the free-living flatworm Macrostomum lignano, by either raising worms in monogamous pairs (no sperm competition) or in promiscuous groups (intense sperm competition). Worms in groups produced larger testes and smaller ovaries as predicted by sex allocation theory and as previously documented in this species. However, we found no evidence for an effect of group size on sperm morphology, measured as total sperm length, sperm body length, and the length of two different sperm appendages. We conclude that M. lignano may either be incapable of adjusting the sperm morphology in a phenotypically plastic way and/or that there might be no benefit of phenotypic plasticity in sperm traits in this specie
Does Financial Education Impact Financial Literacy and Financial Behavior, and if so, When?
In a meta-analysis of 126 impact evaluation studies, we find that financial education significantly impacts financial behavior and, to an even larger extent, financial literacy. These results also hold for the subsample of randomized experiments (RCTs). However, intervention impacts are highly heterogeneous: Financial education is less effective for low-income clients as well as in low and lower-middle income economies. Specific behaviors, such as the handling of debt, are more difficult to influence and mandatory financial education tentatively appears to be less effective. Thus, intervention success depends crucially on increasing education intensity and offering financial education at a 'teachable moment'
Costs of mating competition limit male lifetime breeding success in polygynous mammals.
This is the accepted version of the paper. The final published version is available from the Royal Society at http://rspb.royalsocietypublishing.org/content/281/1786/20140418.abstract.Although differences in breeding lifespan are an important source of variation in male fitness, the factors affecting the breeding tenure of males have seldom been explored. Here, we use cross-species comparisons to investigate the correlates of breeding lifespan in male mammals. Our results show that male breeding lifespan depends on the extent of polygyny, which reflects the relative intensity of competition for access to females. Males have relatively short breeding tenure in species where individuals have the potential to monopolize mating with multiple females, and longer ones where individuals defend one female at a time. Male breeding tenure is also shorter in species in which females breed frequently than in those where females breed less frequently, suggesting that the costs of guarding females may contribute to limiting tenure length. As a consequence of these relationships, estimates of skew in male breeding success within seasons overestimate skew calculated across the lifetime and, in several polygynous species, variance in lifetime breeding success is not substantially higher in males than in females.The Leverhulme Trust, the Isaac Newton Trust, and the European Research Council provided the funding for this study
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HexagDLy - Processing hexagonally sampled data with CNNs in PyTorch
HexagDLy is a Python-library extending the PyTorch deep learning framework
with convolution and pooling operations on hexagonal grids. It aims to ease the
access to convolutional neural networks for applications that rely on
hexagonally sampled data as, for example, commonly found in ground-based
astroparticle physics experiments
Towards Constructive Hybrid Semantics
With hybrid systems becoming ever more pervasive, the underlying semantic challenges emerge in their entirety. The need for principled semantic foundations has been recognized previously in the case of discrete computation and discrete data, with subsequent implementations in programming languages and proof assistants. Hybrid systems, contrastingly, do not directly fit into the classical semantic paradigms due to the presence of quite specific "non-programmable" features, such as Zeno behaviour and the inherent indispensable reliance on a notion of continuous time. Here, we analyze the phenomenon of hybrid semantics from a constructive viewpoint. In doing so, we propose a monad-based semantics, generic over a given ordered monoid representing the time domain, hence abstracting from the monoid of constructive reals. We implement our construction as a higher inductive-inductive type in the recent cubical extension of the Agda proof assistant, significantly using state-of-the-art advances of homotopy type theory. We show that classically, i.e. under the axiom of choice, our construction admits a charaterization in terms of directed sequence completion
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