THE EFFECTS OF BOLDNESS ON THREAT-SENSITIVE DECISIONS IN FISHES

Personality describes the consistent, individual differences in the behaviour we observe among human and non-human models alike. One of the components of human and animal personality which has sparked interest, is the boldness trait. Boldness is the propensity to engage in risk taking behaviour, and as such, has important ecological impacts on the interactions between animals. By changing the amount of risk taking behaviour, boldness effectively alters the outcome of predator-prey interactions. Boldness may alter a prey’s decision between an antipredator response or continuing other important behaviours (e.g. foraging or reproduction) when faced with a predator. The difference in response may be the result of a changed perception in the amount of local risk, or due to a differential amount of information gathered from the environment. In either case, more information about local predators increases the likelihood that a prey will appropriately respond to a threat. In aquatic systems, prey often receive chemical information from the scent of predators or chemical released by conspecifics. Specifically, alarm cues are released following damage to the skin tissue of many prey species and thus are reliable indicators of risk. These alarm cues are often the first line of prey defense, as they degrade slowly and are passed through the aquatic medium in currents. Secondary information regarding local risk often comes from the visual cues associated with the sight of a predator or frightened conspecifics. This provides prey with reliable information about risk since the transmission distance of visual cues is limited in water and further lessened by vegetation and turbidity. My experiment demonstrates that boldness in fathead minnows (Pimephales promelas) is stable over shorter temporal scales, and subsequently, affects how minnows acclimate to their environment and respond to visual and chemical information on local threats. In low risk environments, personality and turbidity strongly affect the threat-sensitive response of minnows. Shy minnows demonstrate no antipredator response when in turbid water and bold minnows elicit a strong fright response in turbid conditions. In clear conditions, the opposite occurs with large fright responses in shy minnows and no response in bold minnows. Conversely, when minnows were exposed to high amounts of environmental risk through the exposure to alarm cues, they all elicit strong fright responses regardless of personality or turbidity. This is the first experiment to investigate the complex interplay of personality and multiple cue types on the threat-sensitive response of prey fish

A linear-time benchmarking tool for generalized surface codes

Quantum information processors need to be protected against errors and faults. One of the most widely considered fault-tolerant architecture is based on surface codes. While the general principles of these codes are well understood and basic code properties such as minimum distance and rate are easy to characterize, a code's average performance depends on the detailed geometric layout of the qubits. To date, optimizing a surface code architecture and comparing different geometric layouts relies on costly numerical simulations. Here, we propose a benchmarking algorithm for simulating the performance of surface codes, and generalizations thereof, that runs in linear time. We implemented this algorithm in a software that generates performance reports and allows to quickly compare different architectures

Similar Breeding Success of Bearded Vultures in Disturbed and Undisturbed Areas Shows Evidence of Adaptation Capabilities

Retraction notice: We have been informed that because of logistical reasons the authors of Comor et al. (2019) were unable able to provide the answers requested by Duriez et al. (2020) regarding the protocols, the quantitative data, or the small and unbalanced sample sizes. At the authors\u27 request, the article by Comor et al. published in Human–Wildlife Interactions 13(3) has been retracted. Human activities are usually considered as disturbing factors impeding the breeding success of wild animals. Protected areas can then be set up to restrict such activities aiming to improve wildlife’s breeding success and conservation. To test for the efficiency of these measures, we compared the breeding success of bearded vultures (Gypaetus barbatus) in the western French Pyrenees from autumn 2011 to spring 2017, where eyries are located either within or outside restricted areas, where potentially disturbing activities are restricted (e.g., helicopter flights, forestry works, hunting, paragliding). We monitored reproducing bearded vultures and checked the breeding success at different stages (laying, incubation, hatching, and survival at 2 months) of formed pairs. We then compared the success of each stage between eyries located in restricted and non-restricted areas, including weather data in our model. We found that the breeding success was similar in both types of areas, but that is was negatively impacted by precipitations, which may directly affect the ability of the egg or chick to withstand cold. We also focused on the potential disturbance of hunting parties on the behavior of bearded vultures and found no evidence that hunting was perceived as a threat by bearded vultures; they may in fact benefit from gut piles. Hence, our comparison of the breeding success between eyries located in restricted versus non-restricted areas shows no detrimental impact of human activities and calls for some studies to assess the effectiveness of restrictions in improving the breeding success of bearded vultures, as this species seems to show some degree of tolerance to human activities and may significantly suffer from harsh winter weather in this area

Attitude and Position Control of a Flapping Micro Aerial Vehicle

International audienc

Synthèse et caractérisation d'analogues de peptides antimicrobiens riches en arginines

La résistance antimicrobienne est un problème de santé publique de plus en plus inquiétant. En effet, si ce problème n'est pas contrôlé dès maintenant, dans les prochaines années, nous pourrions arriver dans une ère post-antibiotique où de simples infections pourraient recommencer à tuer. Afin d'éviter de tels enjeux, il est primordial que de nouveaux antibiotiques soient développés pour remplacer les médicaments contre lesquels les bactéries se sont adaptées. De toutes nouvelles classes de médicaments seraient nécessaires et l'une d'entre elles est la classe des peptides antimicrobiens. Ces segments protéiques sont retrouvés dans une impressionnante variété d'organismes et sont utilisés comme première ligne de défense contre les infections bactériennes. Le fonctionnement de ces molécules n'est pas entièrement compris, mais il est présumé qu'elles créent des pores dans les membranes bactériennes, causant ainsi la mort des cellules attaquées. Ces molécules ont un énorme potentiel, mais de nombreux problèmes empêchent leur utilisation clinique. Dans le laboratoire du Professeur Voyer, un peptide modèle, analogue des peptides antimicrobiens, a été synthétisé. Ce peptide composé de 10 leucines et de quatre phénylalanines modifiées par des éthers-couronnes a été modifié de façon systématique pour tenter de comprendre les déterminants de l'activité et de la sélectivité des peptides antimicrobiens. Dans ce mémoire, la synthèse et la caractérisation des analogues dans lesquels trois leucines ont été substituées par des acides aminés cationiques seront discutées. Ces peptides ont été caractérisés par des études biophysiques comme le dichroïsme circulaire, l'infrarouge à transformée de Fourier et le relargage de la calcéine par fluorescence. De plus, des tests d'activité biologique comme l'activité antimicrobienne et l'activité hémolytique ont aussi été réalisés et sont présentés dans le présent mémoire

STRONG REPRESENTATION OF THE QUANTILE FUNCTION FOR LEFT TRUNCATED AND DEPENDENT DATA

International audienceLet (X i) i≥1 be a sequence of strong-mixing random variables with common unknown absolutely continuous distribution function F subject to random left truncation. Let F −1 (p) denote the pth (p ∈]0, 1[) quantile function of the marginal distribution function of the X i 's which is estimated by the sample quantile F −1 n (p). In this paper, we derive the strong consistency and a strong representation for F −1 n (p), the quantile function of the Lynden-Bell estimator of F for strong-mixing processes

Apport croisé de la modélisation déterministe et géostatistique. Exemple des concentrations en nitrates de la Seine.

5pages+résuméLe long des réseaux hydrographiques, l'espacement des stations de mesure des concentrations et l' hétérogénéité des mesures compliquent le calage des modèles géostatistiques nécessaires à l'estimation des concentrations (Bernard-Michel et de Fouquet, 2006). Le recours à un modèle déterministe peut-il permettre de remédier à la rareté des mesures, en fournissant débit, concentrations sur tout le domaine simulé ? Nous examinons par bief les résultats du modèle PROSE qui décrit la Seine et la Marne peu avant leur confluence jusqu'à Poses. Temporellement les mesures et la simulation PROSE sont ajustables en modèle linéaire de corégionalisation. Spatialement, le cokrigeage permet de recaler les conditions aux limites, et donc la simulation, aux mesures de contrôle. reproduisant la variabilité spatiale, mais faiblement corrélé aux mesures, le modèle PROSE s'interprète alors en terme de simulation non conditionnelle. Enfin, un modèle de variogramme tri-variable débit-flux-concentrations est ajusté spatialement

Caractérisation spatiale et temporelle de la qualité des « Masses d’Eau Cours d’Eau »

Focalisé sur les indicateurs physico-chimiques soutenant la biologie des cours d’eau, l’article examine l’interpolation de ce type de mesures, dans le temps et l’espace, pour le calcul des indices légaux requis par la Directive Cadre Européenne sur l’Eau. En effet, le calcul d’indicateurs statistiques, à partir d’une information très lacunaire, pose problème. Différentes méthodes de calcul du quantile 90 par station sont-elles équivalentes? Comment cet indicateur varie-t-il spatialement? Le Réseau National de Bassin français fournit-il suffisamment d’information pour une caractérisation pertinente de la qualité des eaux?Les sorties du modèle déterministe ProSe appliqué à la Seine, à pas de temps journalier, sont utilisées pour comparer différentes méthodes de calcul des indicateurs. Les résultats déduits du modèle exhaustif sont comparés à ceux calculés après un échantillonnage simulant celui du réseau de surveillance.Deux calculs du quantile 90 temporel par station sont examinés : le calcul classique fondé sur la fonction de quantile empirique, et une méthode légèrement plus complexe, avec une pondération temporelle et une linéarisation de la fonction de quantile, qui atténue effectivement les biais induits par l’échantillonnage irrégulier durant l’année, ou découlant du nombre restreint de mesures.Trois méthodes de « spatialisation » sont ensuite testées afin d’obtenir des pourcentages d’occurrence des quantiles par classe de qualité dans chaque « Masses d’Eau Cours d’Eau » : le « principe de défaillance » retient la station la plus défavorable; la deuxième méthode calcule la proportion des stations par classe de qualité; la dernière pondère chaque station par son « segment d’influence ». La spatialisation par segments d’influence des quantiles temporels au sein des « Masses d’Eau Cours d’Eau » améliore nettement les estimations des pourcentages d’occurrence, montrant la nécessité de la prise en compte de la localisation des stations lors du calcul d’un indice de qualité.This research aimed to understand how to interpolate discrete measurements, in space and time, in order to calculate physico-chemical indicators in rivers, which are required by the European Water Framework Directive. Linked to this issue, several questions were addressed. Are the different methods used to calculate temporal 90th-percentiles at a given site equivalent? How does this legal indicator vary in space? Does the French National Basin Network provide enough information to make consistent water quality characterization?The daily outputs of the ProSe model applied to the Seine River were used as proxies to compare different calculation methods of the 90th-percentile. The results deduced from the exhaustive model were compared to those calculated, after sampling the outputs according to the monitoring network sampling scheme. Two calculations of the temporal 90th-percentile at a given site were examined: the classical method based on the empirical percentile function and a slightly more complex method that includes temporal weighting and linearization of the empirical percentile function. This second method reduced the estimation bias of the 90th-percentile induced by irregular and/or few measurements.Three methods for spatializing the 90th-percentiles were tested to obtain occurrence percentages of the percentiles for each quality class in each “Stream Water Body”: the “failure principle” consists in keeping only the worst site; the second approach calculates the proportion of sites located in each quality class; the third method allocates an influence segment to each measurement site. Spatializing temporal percentiles in “Stream Water Bodies” by influence segments led to a marked improvement in occurrence percentage estimations and revealed the need to take into account the spatial configuration of measurement sites when calculating a quality indicator

Caractérisation spatiale et temporelle des "Masses d'Eau Cours d'Eau". Spatial and Temporal characterization of "River Water Bodies".

International audienceThis article aims to understand how to extrapolate in space and time discrete measurements in order to calculate physico-chemical indicators in rivers, which are required by the Water Framework Directive. Linked to this issue, few questions are addressed. Does the French National Basin Network provide enough information in order to make consistent water quality maps? How does the temporal indicator - the 90 percentile - vary in space? The outputs of the ProSe model applied to the Seine River are used to compare two different methods for calculating the 90 percentile: the classical method based on the empirical percentile function and a method that aims to reduce the estimation bias of the 90 percentile. This second method includes temporal weighting and linearization o the empirical percentile function, and therefore its application is a little more complex. But with this method the bias induced by irregular and/or few measurements is reduced. Three methods for spatializing the 90 percentiles have been tested in order to obtain occurrence percentages of the percentiles for each quality class. The first one is based on the "failure principle" and consists in keeping only the worst site for the considered "River Water Body". The second one respects the proportion of percentiles located in each quality class, while the third one allocates an influence segment to each measurement site. Spatializing temporal percentiles in "River Water Bodies" by influence segments leads to a marked improvement of occurrence percentage estimations and reveals the necessity to take into account the spatial configuration of measurement sites when calculating a quality indicator