Search results for "Fish"
showing 10 items of 3164 documents
Spatial and temporal variation in larval density of coregonids and their consequences for population size estimation in Finnish lake
2011
Sex and sexual ornamentation associated with survival of the cyprinid fish, Rutilus rutilus, under disease stress
2013
By conveying information of disease resistance, sexual signals may be used as cues for adaptive mate choice. Here we report observations on survival of laboratory-maintained, wild-collected, sexually mature, ready-to-spawn cyprinid fish, Rutilus rutilus (roach), under accidental epidemic attributed to Flavobacterium psychrophilum, diagnosed using species-specific PCR. The fish were maintained in a single tank. During the 27 days observation period, both the proportion of fish surviving the infection as well as the length-adjusted mean survival time of the fish that died was the highest among the high-ornamented males with large breeding tubercles, intermediary among the low-ornamented males…
An experimental approach to oxidative stress effect on sperm motility and DNA fragmentation
2018
En el estudio de la fertilidad masculina en todas las especies animales, la movilidad espermática, junto a la concentración y morfometría son los parámetros principales y más básicos en la evaluación de la calidad de los espermatozoides. La infertilidad masculina habitualmente se asocia con tasas anormales de estos parámetros seminales. Aún teniendo, los espermatozoides tasas adecuadas de todos estos parámetros no se puede garantizar la capacidad de fertilizar y/o desarrollar un cigoto. Por lo tanto, está claro que el examen rutinario del semen y los espermatozoides en la eyaculación no puede evaluar otros parámetros importantes en el proceso de fecundación como es capacitación espermática …
Spatial variability in stable carbon and nitrogen isotope ratios in a Mediterranean coastal lagoon (Mauguio, France).
2003
Using uncertain preferential information from stakeholders to assess the acceptability of alternative forest management plans
2017
In forest management planning, participatory planning processes are often encouraged as a means to acquire relevant information and to enhance the stakeholders' acceptability of alternative plans. This requires the aggregation of the stakeholders' preferences that can be done in a wide variety of manners. The aggregation process strives to reduce the information into a single set of preferences that simplifies the information and allows for the use of discrete decision support tools. Depending on how the preferences are aggregated, a wide range of plan rankings can emerge. Although this range of ranking complicates the issue of plan selection, it does highlight the uncertainty involved in a…
The variable food webs in cold-water lakes
2022
Étude d'un système de stéréo-vision hybride
2013
National audience; On considère dans ce travail un système de vision hybride fixe composé d'une caméra fisheye et d'une caméra PTZ dans un environnement rigide. Nous souhaitons être en mesure d'orienter la caméra mécanisée sur une cible visible depuis l'image omnidirectionnelle de manière à obtenir une image de bonne définition de l'objet d'intérêt à partir de la caméra PTZ. Nous proposons dans cet article d'utiliser la modélisation sphérique des images ainsi que les propriétés de la géométrie épipolaire afin d'initialiser la localisation de la cible dans la caméra PTZ.
Towards Robust Adaptive Least-Squares Parameter Estimation with Internal Feedback
1998
Abstract The new concepts of the ‘covariance matrix normalization’ and the ‘cascade’ structure of the adaptive least-squares estimator are shown to generalize and extend the use of internal information feedback in various robustness/alertness-oriented modifications to the standard ALS estimation algorithm. In the cascade estimation structure it is possible to ‘naturally’ stabilize, rather than maximize, the information matrix so that the covariance windup and blowup are effectively eliminated and the celebrated square root update of the covariance matrix is no longer needed Consequently, a new, ‘single-loop/cascade’ ALS MIMO estimation algorithm, enabling to effectively track both slow and …
Itô-Stratonovitch Formula for the Wave Equation on a Torus
2010
We give an Ito-Stratonovitch formula for the wave equation on a torus, where we have no stochastic process associated to this partial differential equation. This gives a generalization of the classical Ito-Stratonovitch equation for diffusion in semi-group theory established by ourself in [18], [20].
Solving Conflicts among Conservation, Economic, and Social Objectives in Boreal Production Forest Landscapes: Fennoscandian Perspectives
2018
This chapter discusses challenges and possibilities involved in preserving biological diversity and the diversity of ecosystem services in the boreal zone and yet at the same time maintaining intensive timber extraction in boreal forests. Our focus is on Fennoscandian forests at the landscapes level, and we consider economic, social and ecological in the sustainability of forest management. We provide an outlook to boreal forest ecosystems and their history, and an overview of the forestry practices and policies that aim to ensure multi-functionality of Fennoscandian forests, i.e. diversity of efforts on sustaining biodiversity, timber production and other ecosystem services from forest lan…