Evolution of populations expanding on curved surfaces

This is the author accepted manuscript. The final version is available from EPL Association via the DOI in this recordThe expansion of a population into new habitat is a transient process that leaves its footprints in the genetic composition of the expanding population. How the structure of the environment shapes the population front and the evolutionary dynamics during such a range expansion is little understood. Here, we investigate the evolutionary dynamics of populations consisting of many selectively neutral genotypes expanding on curved surfaces. Using a combination of individual-based off-lattice simulations, geometrical arguments, and lattice-based stepping-stone simulations, we characterise the effect of individual bumps on an otherwise flat surface. Compared to the case of a range expansion on a flat surface, we observe a transient relative increase, followed by a decrease, in neutral genetic diversity at the population front. In addition, we find that individuals at the sides of the bump have a dramatically increased expected number of descendants, while their neighbours closer to the bump's centre are far less lucky. Both observations can be explained using an analytical description of straight paths (geodesics) on the curved surface. Complementing previous studies of heterogeneous flat environments, the findings here build our understanding of how complex environments shape the evolutionary dynamics of expanding populations.Nederlandse Organisatie voor Wetenschappelijk Onderzoek I (NWO-I)American Physical SocietySociedade Brasileira de FísicaFAPESPCenter for Computation and Visualization, Brown Universit

Children interpretation of emotional body language displayed by a robot

Previous results show that adults are able to interpret different key poses displayed by the robot and also that changing the head position affects the expressiveness of the key poses in a consistent way. Moving the head down leads to decreased arousal (the level of energy), valence (positive or negative) and stance (approaching or avoiding) whereas moving the head up produces an increase along these dimensions [1]. Hence, changing the head position during an interaction should send intuitive signals which could be used during an interaction. The ALIZ-E target group are children between the age of 8 and 11. Existing results suggest that they would be able to interpret human emotional body language [2, 3]. Based on these results, an experiment was conducted to test whether the results of [1] can be applied to children. If yes body postures and head position could be used to convey emotions during an interaction.Peer reviewe

Mapping of stones and their deterioration forms : the Clock Tower, Venice (Italy)

The HYPERION EU project aims to develop a Decision Support System to improve resilience and sustainable reconstruction of historic areas faced with climate change and extreme events. In this context, Venice presents an outstanding example of urban and architectural complexity and richness. The mapping of the ornamental stones of the facade of the Venice Clock Tower (Torre dell'Orologio) and their deterioration patterns acts as a milestone on which to build the knowledge-acquisition process of the system as regards stone artefacts and their decay products. The Clock Tower is an early Renaissance building (1499) in Lombardesque style and stands over the entrance to the Mercerie on the northern side of St. Mark's Square. Detailed surveys and mapping of both building materials (mainly stones) and deterioration patterns were carried out, the latter following the glossary of weathering forms, coupled with an easy-to-use scale of evaluation of their intensity. The data output consists of several monothematic maps which can be handled separately, each one focusing on precise lithological or specific deterioration aspects. This study also proposes a simple approach to summarizing the total state of deterioration of the building in the form of a Total Deterioration Rank (TDR) and its representation. The stones used in the facade are regional (Ammonitico Rosso and Scaglia Rossa) and extra-regional limestones (Istrian Stone), as well as Mediterranean white and coloured marbles and stones already used in antiquity (i.e., Fior di Pesco or marmor chalcidicum, lapis porphyrites, a volcanic rock from the Egyptian Eastern Desert, Proconnesian marble from the Island of Marmara, Pavonazzetto toscano and white Carrara marble from the Italian Apuan Alps). The most frequent forms of deterioration detected are black crusts, patinas, discoloration and patterns linked to erosion processes. The interrelation of different mappings led to a number of useful considerations concerning differences in the effectiveness of maintenance procedures between public and private management of the monument

Structural role of the tyrosine residues of cytochrome c

The tertiary structures of horse, tuna, Neurospora crassa, horse [Hse65,Leu67]- and horse [Hse65,Leu74]-cytochromes c were studied with high-resolution 1H n.m.r. spectroscopy. The amino acid sequences of these proteins differ at position 46, which is occupied by phenylalanine in the horse proteins but by tyrosine in the remaining two, and at positions 67, 74 and 97, which are all occupied by tyrosine residues in horse and tuna cytochrome c but in the other proteins are substituted by phenylalanine or leucine, though there is only one such substitution per protein. The various aromatic-amino-acid substitutions do not seriously affect the protein structure

The collective effect of finite-sized inhomogeneities on the spatial spread of populations in two dimensions

This is the final version. Available on open access from the Royal Society via the DOI in this recordData accessibility: The source code corresponding to the event-based solution and the solution of the Eikonal equation is available on Zenodo, https://doi.org/10.5281/zenodo.5513567, and GitHub, https://github.com/wmoebius/inhomogeneities_one2many.The dynamics of a population expanding into unoccupied habitat has been primarily studied for situations in which growth and dispersal parameters are uniform in space or vary in one dimension. Here, we study the influence of finite-sized individual inhomogeneities and their collective effect on front speed if randomly placed in a two-dimensional habitat. We use an individual-based model to investigate the front dynamics for a region in which dispersal or growth of individuals is reduced to zero (obstacles) or increased above the background (hotspots), respectively. In a regime where front dynamics is determined by a local front speed only, a principle of least time can be employed to predict front speed and shape. The resulting analytical solutions motivate an event-based algorithm illustrating the effects of several obstacles or hotspots. We finally apply the principle of least time to large heterogeneous environments by solving the Eikonal equation numerically. Obstacles lead to a slow-down that is dominated by the number density and width of obstacles, but not by their precise shape. Hotspots result in a speed-up, which we characterize as function of hotspot strength and density. Our findings emphasize the importance of taking the dimensionality of the environment into account.Stichting voor Fundamenteel Onderzoek der Materie (FOM), The NetherlandsCOST (European Cooperation in Science and Technology)National Science Foundation (NSF

Misanthropic Person Memory when the Need to Self-Enhance is Absent

This research examined the role that the removal of the need or ability to self-enhance can play in the misanthropic processing of attributed behavioral information (i.e., remembering best negative, internally attributed behaviors and positive externally attributed behaviors). Experiment 1demonstrated that removing a person’s need to self-enhance by increasing his or her self-esteem eliminated misanthropic memory, whereas misanthropy was preserved for control participants and perceivers who had experienced a decrease in self-esteem. Furthermore, controlling for participants’ self-evaluations eliminated the memory pattern differences between the two experimental conditions. Experiment 2 demonstrated that canceling the ability to self-enhance by having perceivers form an impression of themselves eliminated the misanthropy effect. However, the misanthropy effect was replicated when perceivers learned about an unknown other. The results were discussed with regard to the situations and factors that can increase or reduce the need to self-enhance and their implications for social information processing.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/68679/2/10.1177_0146167299025002011.pd