Search results for "Formes"
showing 10 items of 309 documents
Vitesse, accessibilité et étalement urbain ; analyse et application à l'aire urbaine dijonnaise
2003
The set of themes of the city is approached primarily by the means of the residential density. This concept is analyzed from a purely conceptual point of view, then more theoretical (thus making use of rather traditional econometric models: Clark, Newling) for finally being applied to the agglomeration dijonnaise like with its urban surface. One releases the great urban structures thus revealing an intermediate city between the model monocentric and polycentric. The two components are analyzed successively starting from the concept of residential density. Taking as assumption that the cities are dynamic, the second stage is that of urban sprawl out. A first introductory approach attempts to…
Combining population genomics with demographic analyses highlights habitat patchiness and larval dispersal as determinants of connectivity in coastal…
2022
Gene flow shapes spatial genetic structure and the potential for local adaptation. Among marine animals with nonmigratory adults, the presence or absence of a pelagic larval stage is thought to be a key determinant in shaping gene flow and the genetic structure of populations. In addition, the spatial distribution of suitable habitats is expected to influence the distribution of biological populations and their connectivity patterns. We used whole genome sequencing to study demographic history and reduced representation (double-digest restriction associated DNA) sequencing data to analyse spatial genetic structure in broadnosed pipefish (Syngnathus typhle). Its main habitat is eelgrass beds…
Breeding near heterospecifics as a defence against brood parasites: can redstarts lower probability of cuckoo parasitism using neighbours?
2022
Breeding habitat choice based on the attraction to other species can provide valuable social information and protection benefits. In birds, species with overlapping resources can be a cue of good quality habitats; species with shared predators and/or brood parasites can increase joint vigilance or cooperative mobbing, while raptors may provide a protective umbrella against these threats. We tested whether the migratory common redstart (Phoenicurus phoenicurus) is attracted to breed near active nests of the great tit (Parus major), a keystone-information source for migrant passerine birds, or a top predator, the northern goshawk (Accipiter gentilis). This system is unique to test these quest…
Le choix de la forme organisationnelle en matière d’investissement en R&D à l’étranger par les firmes multinationales:la contribution de la théorie d…
2008
(VF)L’objectif de ce papier est d’évaluer la contribution de la théorie des coûts de transaction à l’explication du choix du mode de gouvernance des activités de R&D à l’étranger par les firmes multinationales. Nous avons identifié principalement trois grandes formes organisationnelles en matière d’investissement en R&D à l’étranger:l’internalisation totale, les alliances en R&D et l’externalisation totale (licences unilatérales). Suite à une étude quantitative par le biais d’un questionnaire diffusé auprès de 769 firmes multinationales, nos principaux résultats montrent que le choix de l’internalisation des activités de R&D est favorisé en cas de fréquence élevée des transactions, le choix…
Analogia i canvi morfològic : a propòsit de les formes verbals velaritzades
1995
An important series of verbs of the second conjugation exists in Catalan, characterized by a velar obstruent between the radical and the inflectional affixes. This velar segment, which in modern Catalan acts as an extension of the radical, has a heterogeneous historical origin. In short, in certain cases it stems from the strengthening of the glide of the Latin strong perfects in -UI (where w > gw > g); in others, it is justified by the maintaining of the final consonant of the radical in certain forms of the present in verbs such as dico or stringere (DICO > dic, DICAM > diga ...); in others, finally, it is due to changes of a purely analogical nature. In order to explain the l…
Distribution and biology of the Blackmouth catshark Galeus melastomus in the Strait of Sicily (Central Mediterranean Sea)
2009
The Blackmouth catshark, Galeus melastomus, Rafinesque, 1810 (Carcharhiniformes; Scyliorhinidae), is a common, although at present discarded, by- catch of the bottom trawl fisheries in the Strait of Sicily. Given its ecological interest, data gathered in experimental bottom trawl surveys were analysed in order to describe its distribution and main biological traits. The Blackmouth catshark was sampled almost exclusively on the upper slope (200-800), showing the highest frequency of occurrence (69-100%), biomass (BI; 10-85 kg*km-2) and density (DI; 54-506 N*km-2) indexes in the deeper (501-800m) grounds. Individual size (total length, TL, mm) were between 70-590 and 90-510 in females and mal…
Intestinal distribution and fecundity of two species ofDiplostomumparasites in definitive hosts
2005
This paper investigated the intestinal distribution and fecundity of 2 species ofDiplostomumparasites,D. spathaceumandD. pseudospathaceum, in 2 species of definitive hosts, herring gull (Larus argentatus) and common gull (L. canus), using both empirical field data and experimental infections. At the level of individual hosts, the parasite species occupied different parts within the intestine, but the fecundity of the worms, measured as the number of eggs in the uterus, did not differ between the parasite species except in wild common gulls. Interestingly, egg numbers in individual hosts were positively correlated between the parasite species suggesting that some birds provided better resour…
Intra-populational and intra-individual mosaicisms of Uranoscopus scaber L. (Perciformes, Uranoscopidae)
1991
Intra-populational and intra-individual mosaicisms of Uranoscopus scaber L. (Perciformes, Uranoscopidae)
Evaluation of waterborne exposure to heavy metals in innate immune defences present on skin mucus of gilthead seabream (Sparus aurata)
2015
Aquatic animals are continuously exposed to chemical pollutants but the effects evoked in skin surfaces, which receive the most direct contact with them, are poorly investigated. Terminal carbohydrate composition and immunological components present in skin mucus of gilthead seabream (Sparus aurata L.) specimens exposed to waterborne sublethal dosages of heavy metals [arsenic (As2O3), cadmium (CdCl2) and mercury (CH3HgCl) at 5, 5 and 0.04 μM, respectively for 2, 10 and 30 days were analysed. Moreover, the presence of a fucose binding lectin (FBL) was evaluated by western blot and the protein profiles were by SDS-PAGE and HPLC. Results showed little effects of heavy metals in the presence of…
Three new species of the subgenus Neoribates (Neoribates) (Acari, Oribatida, Parakalummidae) from Nepal
2014
Three new parakalummid mites of the subgenus Neoribates (Neoribates), N. (N.) parabulanovae sp. n., N. (N.) paramacrosacculatus sp. n. and N. (N.) pararotundus sp. n., are described from Nepalese soils. Neoribates (Neoribates) parabulanovae sp. n. is morphologically most similar to N. (N.) bulanovae Grishina, 2009, N. (N.) rotundus Aoki, 1982 and N. (N.) setiger Balogh & Mahunka, 1978, however, it differs from N. (N.) bulanovae by the body length, body and leg integument, morphology of bothridial setae, absence of aggenital setae, length of interlamellar setae and location of adanal setae ad3; from N. (N.) rotundus by the body size, body integument, morphology of bothridial setae and le…