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Colour signals are often made up of a number of colour patches. The position of these patches within a pattern has the potential to influence signal conspicuousness, especially if viewers attend to local rather than global aspects of the colour pattern. If local contrast is important, then signal efficacy should be highest when highly contrasting patches are adjacent; if local contrast is not important, contrasting colours can be anywhere in the pattern. We tested whether global or local colour patch contrast influenced the attractiveness of male guppies, Poecilia reticulata. We assessed contrast on both global and local scales using two methods. The first, overall pattern contrast, estimates the global pattern contrast without accounting for which colours are adjacent. The second, boundary strength analysis, accounts for local contrast by estimating the contrast intensity (ΔS) and contact lengths between adjacent patches. We tested behaviour under three different light environments: blue, broad spectrum (control) and red to modify visual contrast. The light environment had a significant effect on all measures of colour pattern contrast. The male overall pattern contrast measures did not affect female preferences under the three light environments. The coefficient of variation (CV) of chromatic ΔS was the only measure to show a significant effect on female preferences. Females favoured males that displayed high variation in local contrast (high CV of ΔS, independently of the light environment). Therefore, variation in local visual contrast appears to be more important than overall pattern contrast in guppies, regardless of the light environment.

In this paper, we present a mathematical model for the prediction of chimney fires using data collected by the Twente safety region over the years 2004 up to 2015. The explanatory variables used are the number of inhabitants per areal unit of 500 by 500 metres, the daily mean temperature and an indicator variable for October. Spatially and temporally correlated noise is added to be able to capture latent factors such as human behaviour. The model is validated using the data over the years 2016 and 2017. The model is implemented as a dashboard on a public website and yields as output a hazard map for chimney fires in Twente based on the weather forecast for the coming six days. This way, the dashboard can be used for prevention and planning purposes.

We discuss recent methodological developments in inhomogeneous summary statistics and envelope testing and study their applications in the field of spatial point pattern analysis. Specifically, we use these methods to test McGill’s theory of biodiversity. This theory is based upon three axioms: individuals of the same species cluster together, many rare species co-exist with a few common ones and individuals of different species grow independently of each other. We assess the validity of the first and third axioms for data obtained from a 50 hectare plot on Barro Colorado Island.

Introduction:malgré la vaccination par le BCG, le risque de développer la tuberculose chez les jeunes enfants dans les régions endémiques reste plus élevé après exposition au cas de tuberculose chez l´adulte. Le but de cette étude était de réduire le risque de tuberculose active chez les enfants contacts des cas index adultes à domicile. Méthodes:une étude transversale multisite (avril 2016-janvier 2019) a été réalisée sur des enfants de 0 à 59 mois, contacts des cas index à domicile, dépistés et suivis au centre pédiatrique de Bangui. Résultats:cinq cent vingt- quatre (524) enfants ont été enregistrés. La moyenne d´âge était de 2 ans et 1 mois et le sex ratio garçon/fille de 1,02. Environ quatre-vingt-huit pourcent (88,5%) des contacts étaient vaccinés avec le BCG contre 11,5% non vaccinés. Dans plus de la moitié des cas (52%), les contacts et les cas index ont partagé la même chambre et le temps de contact journalier était supérieur à 12h dans 56% des ménages. Un peu plus de neuf pourcent (9,35%) des contacts avaient une IDR positive. Tous les enfants ont été mis sous chimioprophylaxie à base de Rifampicine + Isoniazide selon les directives nationales et malgré cela, 14 soit 2,67% ont développé une tuberculose active dont 13 formes pulmonaires et une forme ganglionnaire. Conclusion:la chimio prophylaxie tuberculeuse a sans doute permis de réduire considérablement le risque de survenue de la tuberculose chez des enfants ayant été en contact avec les cas index à domicile.

The spatial distribution of a variable, such as the energy consumption per company, is usually plotted by colouring regions of the study area according to an underlying table which is already protected from disclosing sensitive information. The result is often heavily influenced by the shape and size of the regions. In this paper, we are interested in producing a continuous plot of the variable directly from microdata and we protect it by adding random noise. We consider a simple attacker scenario and develop an appropriate sensitivity rule that can be used to determine the amount of noise needed to protect the plot from disclosing private information.

Accurate knowledge of species colour discrimination is fundamental to explain colour based behaviours and the evolution of colour patterns. We tested how the receptor noise limited model, widely used in behavioural ecology, matched actual colour discrimination thresholds obtained using behavioural tests. Guppies (Poecilia reticulata) were first trained to push a target coloured disk placed among eight grey disks of various luminances on a grey plate. Guppies were then tested to find target disks, which varied in colour contrast from the plate. The target disks followed a gradient going from high contrast to inconspicuous against the grey background. We plotted the percentage of correct choices of each colour in the gradient against the model prediction and determined the discrimination thresholds using the inflection point of the fitted sigmoid curve. We performed the experiment on six colour gradients: red, orange, yellow, green, blue and purple. Four colour gradients: red, orange, green and blue, showed a discrimination threshold that matched the model predictions. However, deviations of the model for the yellow and purple gradients suggest that ecological relevance of some colours could affect decision-making in behavioural tests and that we can no longer assume that the rules for colour discrimination are independent of colours.

We propose new summary statistics for intensity-reweighted moment stationary marked point processes with particular emphasis on discrete marks. The new statistics are based on the $n$-point correlation functions and reduce to cross $J$- and $D$-functions when stationarity holds. We explore the relationships between the various functions and discuss their explicit forms under specific model assumptions. We derive ratio-unbiased minus sampling estimators for our statistics and illustrate their use on a data set of wildfires.

Submitted by tgoncalv@stj.jus.br (tgoncalv@stj.jus.br) on 2019-09-26T18:30:32Z No. of bitstreams: 2 qui_est_personne_kengne.pdf: 1082634 bytes, checksum: f823579850418cfd1fe7ae781485d6c5 (MD5) license.txt: 1239 bytes, checksum: c9b4c351324448672315a00808efb725 (MD5) Approved for entry into archive by betanial@stj.jus.br (betanial@stj.jus.br) on 2019-10-02T15:40:41Z (GMT) No. of bitstreams: 2 qui_est_personne_kengne.pdf: 1082634 bytes, checksum: f823579850418cfd1fe7ae781485d6c5 (MD5) license.txt: 1239 bytes, checksum: c9b4c351324448672315a00808efb725 (MD5) Made available in DSpace on 2019-10-02T15:40:41Z (GMT). No. of bitstreams: 2 qui_est_personne_kengne.pdf: 1082634 bytes, checksum: f823579850418cfd1fe7ae781485d6c5 (MD5) license.txt: 1239 bytes, checksum: c9b4c351324448672315a00808efb725 (MD5) Previous issue date: 2019 Trata da definição de consumidor no âmbito do direito positivo camaronês. Aborda, ainda, a influência da legislação francesa sobre a camaronesa neste contexto.

This work discusses the contribution of the philosopher Daya Krishna (1924-2007) to the realm of intercultural dialogues. A leading figure of academic Indian philosophy, Daya Krishna left an immense and eclectic, yet mainly unexplored, corpus. Firstly, I offer one approach to his diverse philosophy by focusing on his philosophical project as a whole. His project attempts to unveil the presuppositions of thinking, which can only be effectuated in dialoguing across philosophical traditions founded on different presuppositions. Applying his project to the realm of intercultural dialogues, I begin by questioning the limits encountered by recent intercultural theories aiming at deconstructing Eurocentrism and establishing a global philosophical dialogue while responding to their postmodern European heritages. As a counterpoint, I introduce the challenges of Anglophone Indian philosophers in India, facing an uprooting from their own traditions. They feel this uprooting as cultural subjection, deprived of their own philosophical past. Within this context, Daya Krishna connected isolated communities of thinkers by organizing multilingual dialogues (called 'saṃvāda') between traditional paṇḍits, ulama and Anglophone philosophers. I reconstruct some of these experiments, thereby emphasizing methodological...

Visual pigments can vary across the retina in many vertebrates, but the behavioural consequences of this retinal heterogeneity are unknown. Guppies (Poecilia reticulata) vary dorsoventrally in visual pigments and forage both on the ground and at the water surface, exposing different retinal regions to two very different visual environments. We tested guppy behaviour towards a moving stimulus presented below or above the guppy. We used 12 different narrow-band wavelength stimuli matching each of the opsin peak sensitivities presented either at the top or the bottom of our experimental apparatus. We analysed behaviours of 50 male and 50 female guppies over 4800 trials where a moving stimulus pattern was presented to each guppy. We found that wavelength, position and speed of the stimuli influenced male and female behaviour and seems to be mediated by the long wavelength sensitive photoreceptors. Males also had stronger behavioural responses than females whereas females performed more foraging-related pecking behaviour. Our results suggest that the spatial requirement of visual tasks and their ecological context are important and appear to be partly correlated with photoreceptor arrangement in the retina.

We propose new summary statistics to quantify the association between the components in coverage-reweighted moment stationary multivariate random sets and measures. They are defined in terms of the coverage-reweighted cumulant densities and extend classic functional statistics for stationary random closed sets. We study the relations between these statistics and evaluate them explicitly for a range of models. Unbiased estimators are given for all statistics and applied to simulated examples and to tropical rain forest data.

We propose a new summary statistic for inhomogeneous intensity-reweighted moment stationarity spatio-temporal point processes. The statistic is defined in terms of the $n$-point correlation functions of the point process, and it generalizes the $J$-function when stationarity is assumed. We show that our statistic can be represented in terms of the generating functional and that it is related to the spatio-temporal $K$-function. We further discuss its explicit form under some specific model assumptions and derive ratio-unbiased estimators. We finally illustrate the use of our statistic in practice.

We introduce a class of random fields that can be understood as discrete versions of multicolour polygonal fields built on regular linear tessellations. We focus first on a subclass of consistent polygonal fields, for which we show Markovianity and solvability by means of a dynamic representation. This representation is used to design new sampling techniques for Gibbsian modifi- cations of such fields, a class which covers lattice-based random fields. A flux-based modification is applied to the extraction of the field tracks network from a Synthetic Aperture Radar image of a rural area.

Bulletins de veille Elevages durables

This paper is concerned with inference for renewal processes on the real line that are observed in a broken interval. For such processes, the classic history-based approach cannot be used. Instead, we adapt tools from sequential spatial point process theory to propose a Monte Carlo maximum likelihood estimator that takes into account the missing data. Its efficacy is assessed by means of a simulation study and the missing data reconstruction is illustrated on real data.

Dictionnaire Agroécologie. 2. Forum Territorial de la Culture Scientifique, Technique et Industrielle