Search results for "Formes"
showing 10 items of 309 documents
Prehatching maternal investment and offspring immunity in the pied flycatcher (Ficedula hypoleuca).
2007
Maternal investment in offspring immunity via egg quality may be an adaptive evolutionary strategy shaped by natural selection. We investigated how maternal investment in eggs can influence offspring immunity by conducting two experiments. First, we manipulated foraging performance of the mothers before egg laying by attaching a small weight to their back feathers. During the nestling period, we investigated offspring total antibody production at the age of 7 days and after antibody challenge, and conducted a partial cross-fostering design to separate the effects of the experiment and rearing-related variation on offspring immunity. In a separate experiment, partial cross-fostering with ant…
Halfway up the trophic chain: development of parasite communities in the sparid fish Boops boops
2007
SUMMARYWe examined the patterns of composition and structure of parasite communities in the Mediterranean sparid fish Boops boops along a gradient of fish sizes, using a large sample from a single population. We tested the hypothesis that species forming the core of the bogue parasite fauna (i.e. species which have a wide geographical range and are responsible for recognizable community structure) appear early in the fish ontogeny. The sequential community development observed supported the prediction that core species appear in the fish population earlier than rare and stochastic species. There was also a strong correlation between the order of ‘arrival’ of the species and their overall pr…
Morphological and molecular redescription of the myxozoanUnicapsula pflugfelderiSchubert, Sprague & Reinboth 1975 from two teleost hosts in the M…
2009
Elongate plasmodia with myxosporean spores belonging to the genus Unicapsula, Davis, 1924 were found in the skeletal muscle of the striped seabream, Lithognathus mormyrus (L.), a candidate for the mediterranean aquaculture. The only species of Unicapsula described from the Mediterranean is Unicapsula pflugfelderi Schubert et al. 1975, which occurs in the picarel, Spicara smaris (L.). For morphological and molecular comparison of U. pflugfelderi from S. smaris with Unicapsula sp. from L. mormyrus measurements of plasmodia and spores, ultrastructural details and 18S and 28S rDNA sequences were analysed. Whereas plasmodia were 2-3 times larger in S. smaris than in L. mormyrus (length 2.47-0.81…
Plan d’action suffragiste en faveur de la cause féminine: femmes rédactrices, catalyseurs des réformes sociales et politiques dans l’Angleterre victo…
2019
National audience; La suppression du droit de timbre en 1855 et des taxes sur le papier en 1861, en Angleterre, favorise la création de plusieurs organes de presse dont le magazine féministe The Englishwoman’s Journal (1858-1864). Sa stratégie éditoriale consiste à promouvoir les analyses critiques des journalistes de sexe féminin contre les politiques conservatrices anglaises concernant la condition féminine. Les co-fondatrices du groupe de Langham Place, Barbara Leigh Smith (1827-1891) et Bessie Rayner Parkes (1829-1925), donnent la parole à la communauté féminine qui n’a de véritable possibilité d’expression et de communication que l’écriture. Se dégageant de toute restriction d’expressi…
Surface homeomorphisms with zero dimensional singular set
1998
We prove that if f is an orientation-preserving homeomorphism of a closed orientable surface M whose singular set is totally disconnected, then f is topologically conjugate to a conformal transformation.
Obruchevacanthus ireneae gen. et sp. nov., a new ischnacanthiform (Acanthodii) from the Lower Devonian of Spain
2014
New disarticulated material of typically ischnacanthid scales, tooth whorls, and ?dentigerous jaw bones that occur recurrently together at many levels of the Lower Devonian of the Iberian Chain (Spain) is described. Based on their stratigraphical occurrence, histological evidence and comparison with similar ischnacanthid assemblages from other localities, we suggest including all of these remains in a unique natural assemblage, Obruchevacanthus ireneae gen. et sp. nov. This new taxon shares some features with Trundlelepis cervicostulata from the Lower Devonian of New South Wales (Australia), as for example the presence of a poorly developed pore canal system in their scales. This feature su…
Follow-up trends of parasite community alteration in a marine fish after the Prestige oil-spill: shifting baselines?
2008
This study evaluates the follow-up trends in the composition and structure of the parasite communities in the marine sparid Boops boops after the Prestige oil-spill. A total of 400 fish comprising 11 seasonal samples was analyzed from three impacted localities on the Atlantic coast of Spain. A large number of parasite species was recovered only after the spill thus suggesting a substantial alteration of the marine food webs. Post-spill communities exhibited higher richness and abundance due to the significant changes in the abundance of the common species, the latter indicating accelerated parasite transmission rates. Multivariate analyses at two nested scales detected a directional trend i…
Signals from the deep-sea: Genetic structure, morphometric analysis, and ecological implications of Cyclothone braueri (Pisces, Gonostomatidae) early…
2020
Abstract Cyclothone braueri (Stomiiformes, Gonostomatidae) is a widely distributed fish inhabiting the mesopelagic zone of marine tropical and temperate waters. Constituting one of the largest biomasses of the ocean, C. braueri is a key element in most of the ecological processes occurring in the twilight layer. We focused on the ecological processes linked to early life stages in relation to marine pelagic environmental drivers (temperature, salinity, food availability and geostrophic currents) considering different regions of the Central Mediterranean Sea. A multivariate morphometric analysis was carried out using six parameters with the aim of discerning different larval morphotypes, whi…
Impacts écologiques des formes d'urbanisation : modélisations urbaines et paysagères
2015
The global increase of urbanization during the past decades have induced a progressive artificialization of natural environments. The building of transport infrastructures and new housings causes a landscape fragmentation in an irreversible way and a strong decrease of the connectivity of ecological habitats. Maintaining the functionality of ecological networks is becoming a major goal of sustainable urban planning policies. With a special focus on urban evolutions in the horizon 2030 in the urban area of Besançon in eastern France (residential development and road traffic evolutions), this thesis aims to assess the potential impact of urban forms on landscape connectivity of animal species…
A normative planning approach for the Luxembourg : assessment based on spatial simulation
2015
In Luxembourg, daily mobility patterns of both cross-border workers and residents lead to a strong car dependance. This process encourages urban sprawl. Meanwhile the country is faced to increasing housing needs but has to reduce land consumption. Within this context, the main objective of this thesis is to throw light about the relation between residential growth patterns and daily mobility behaviors. In this way, a normative planning approach has been adopted. This approach proposes new planning norms for achieving a series of planning objectives. Quantitative rules are the tools used to apply the norms.Three steps has been done: i) conception of residential growth scenarios for 2030. By …